ORCID Profile
0000-0001-7048-0706
Current Organisation
The University of Auckland
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Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 10-2015
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 09-2015
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 03-2002
DOI: 10.1097/00003226-200203000-00004
Abstract: To identify the indications for keratoplasty in patients supplied with donor tissue through the New Zealand National Eye Bank. Analysis of penetrating and lamellar keratoplasty data collected by the New Zealand National Eye Bank, Auckland, from 1991 to 1999. In this 9-year period, donor material was supplied for 1370 corneal grafts 1308 for penetrating keratoplasty, 26 for lamellar keratoplasty, and 36 for unspecified grafts. This accounts for a minimum of 85% of the penetrating keratoplasties performed in New Zealand from 1991 to 1999. The leading indications for penetrating keratoplasty were keratoconus (45.6%), pseudophakic or aphakic corneal edema (17.9%), regraft (8.7%), viral keratitis (7.3%), and trauma (5.5%). The average age of patients was 47.5 years (SD = 22.6) and age distribution was bimodal, with peaks in the 3rd and 8th decades. Keratoconus, regraft, and trauma were significantly more common as indicators for penetrating keratoplasty in male patients than female patients however, pseudophakic or aphakic corneal edema was more common in female patients. The majority of transplantation surgery in New Zealand is performed using corneal tissue from the New Zealand National Eye Bank. In this representative study, keratoconus is the leading indicator for penetrating keratoplasty in New Zealand, accounting for a higher proportion than in any other published literature. The other indications, age distribution and gender differences correlate with previous reports. These findings suggest that keratoconus leading to transplantation may have increased prevalence in New Zealand.
Publisher: American Medical Association (AMA)
Date: 05-2010
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 03-2017
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 05-2012
Publisher: BMJ
Date: 03-2004
Abstract: The possible impact of corneal thickness, curvature, and size on the measurement of endothelial cell density (ECD) has largely been ignored in the normal eye. The aim of this study was to investigate the possible impact of the main corneal parameters on the analysis of ECD values at the central, superior, and temporal parts of the corneal surface. All 75 participants (52 females, 23 males) were assessed as part of a pre-cataract surgery investigation. The mean age was 75.7 (SD 10.9) years. Confocal microscopy was used to measure ECD and the percentage of six sided cells at the central, superior, and temporal parts of the cornea. The Orbscan II topography system was used to measure corneal thickness, topography, and horizontal corneal diameter. The mean central ECD measured was 2488 (SD 301) cells/mm(2), compared with 2525 (SD 505) cells/mm(2) in the temporal cornea and 2639 (SD 398) cells/mm(2) in the superior cornea. The regional differences in ECD were not significant (p>0.14). The central ECD was significantly correlated to the central (mean 0.593 (SD 0.039) mm, p = 0.021) as well as the temporal (0.628 (SD 0.039) mm, p<0.001) and the superior corneal thickness (SD 0.644 (SD 0.048) mm, p = 0.018). The mean corneal curvature at the centre (7.7 (SD 0.34) mm, p = 0.002) as well as 3 and 5 mm from the apex was significantly related to ECD (p = 0.008 and p = 0.009, respectively). The study suggests that in an older population, lower ECD values would be expected in thinner and/or steeper corneas.
Publisher: Springer Science and Business Media LLC
Date: 10-06-2005
Publisher: Springer Science and Business Media LLC
Date: 23-05-2015
DOI: 10.1007/S00223-015-0015-4
Abstract: To determine the incidence of adverse ocular side effects following re-challenge in patients who previously developed ocular symptoms following intravenous zoledronate. Secondary data analysis of a large, prospective, randomized, double-blind, placebo-controlled clinical trial was performed. Participants consisted of postmenopausal females with osteopenia randomized to placebo (N = 1000) or zoledronate 5 mg (N = 1001) intravenous infusion. Recruitment occurred over a 2-year period, with the first infusion being administered at recruitment, and subsequent infusions every 18 months. Eight participants developed acute anterior uveitis (AAU) (diagnosed by an ophthalmologist) following the first infusion of zoledronate. Following appropriate ophthalmic treatment, no patients had visual loss or other ocular sequelae. One further participant reported "sore red eyes" but did not attend for ophthalmology review. Six participants declined further infusions. The remaining three participants were administered two further zoledronate infusions, 18 months apart, and none developed any ocular symptoms following each infusion. As a precaution, two of these participants were examined by an ophthalmologist 3 days after their second infusion and neither had ocular symptoms or signs of AAU and no subsequent ocular side effects. AAU following zoledronate infusion is likely to be part of the acute phase response. If treated promptly under the care of an ophthalmologist, the visual prognosis is excellent. The results of this study suggest that the development of AAU should not be a contraindication to further infusion. However, in such cases, patients should be warned of the symptoms of AAU (ocular pain, redness, photophobia or blurred vision) and should be promptly referred to an ophthalmologist if symptoms develop.
Publisher: Elsevier BV
Date: 2010
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 11-2001
DOI: 10.1016/S0886-3350(01)01089-6
Abstract: To compare corneal thickness measurements made by ultrasonic and slit-scanning techniques in normal eyes and in eyes after laser in situ keratomileusis (LASIK). Corneal Diseases and Excimer Laser Research Unit, University of Dundee, Dundee, Scotland. Central corneal thickness (CCT) was measured in 101 eyes of 59 normal subjects and in 30 eyes of 21 post-LASIK patients. Measurements were made with an Orbscan slit-scanning elevation topographer and immediately afterward with an ultrasound pachymeter. The difference in mean CCT between ultrasound (538.0 microm +/- 36.7 [SD]) and Orbscan (566.6 +/- 40.7 microm) pachymetry was statistically significant (P <.001) in the normal eyes the Orbscan measurement was approximately 28 microm higher than that of the ultrasound pachymeter. The difference in mean CCT between the ultrasound and the slit-scanning techniques was also statistically significant in the post-LASIK eyes (mean values 475.3 +/- 50.3 microm and 461.9 +/- 74.2 microm, respectively P <.0001). Differences in CCT in in idual subjects were much more variable in the post-LASIK eyes than in the normal eyes. The Bland and Altman method for assessing clinical agreement between 2 instruments showed that in 95% of cases, the CCT measurements with both instruments would be within 65 microm in normal eyes and 150 microm in post-LASIK eyes. Central corneal thickness measurements were, on average, 28 microm higher with the Orbscan than with the ultrasound pachymeter in normal eyes and 13 microm lower in post-LASIK eyes. The degree of variability within each group indicated that these 2 techniques are not clinically comparable, precluding interchangeable use of their data in planning or assessing corneal surgery.
Publisher: Hindawi Limited
Date: 2014
DOI: 10.1155/2014/848659
Abstract: Purpose. To compare tear film metrics in patients with type 1 diabetes mellitus (DM) and healthy controls and investigate the association between peripheral neuropathy and ocular surface quality. Methods. Dry eye symptoms were quantified in 53 patients with type 1 DM and 40 age-matched controls. Ocular examination included tear film lipid layer thickness grading, tear film stability and quantity measurement, and retinal photography. DM in iduals additionally underwent a detailed neuropathy assessment. Results. Neither mean age nor dry eye symptom scores differed significantly between the DM and control groups ( P = 0.12 and P = 0.33 , resp.). Tear lipid thickness ( P = 0.02 ), stability ( P 0.0001 ), and quantity ( P = 0.01 ) were significantly lower in the DM group. Corneal sensitivity was also reduced in the DM group ( P 0.001 ) and tear film stability was inversely associated with total neuropathy score ( r = - 0.29 , P = 0.03 ). Conclusion. The DM group exhibited significantly reduced tear film stability, secretion, and lipid layer quality relative to the age-matched control group. The negative correlation between tear film parameters and total neuropathy score suggests that ocular surface abnormalities occur in parallel with diabetic peripheral neuropathy.
Publisher: BMJ
Date: 10-1994
Publisher: Wiley
Date: 24-05-2002
DOI: 10.1046/J.1442-9071.2002.00524.X
Abstract: The purpose of this study was to identify the in vivo microstructural characteristics of an animal model of 'epithelialization of the endothelium' that are similar in appearance to the in vivo confocal microscopical appearance of corneal endothelium previously thought to be diagnostic of irido-corneal endothelial syndrome, and correlate these observations with ex vivo in situ confocal microscopical analysis. A rat model (n = 8 eyes)of transient 'epithelialization of the endothelium' resulting from superficial corneal trauma, was developed and analysed using in vivo confocal microscopy. One animal was killed at 48 hand the cornea was immuno-labelled and analysed, using ex vivo in situ confocal digital image reconstruction. Reversible 'epithelialization of the endothelium' was observed by in vivo confocal microscopy 48 h after superficial corneal trauma in all eight eyes. Ex vivo in situ analysis failed to demonstrate immunohistological characteristics of epithelialization. In vivo confocal microscopy is based on optical principles, and as a result various structural alterations may present with apparently identical characteristics that should be interpreted cautiously, on the basis of the presented clinicopathological observations.
Publisher: Wiley
Date: 09-03-2017
DOI: 10.1111/CEO.12922
Abstract: A contemporary benchmark for the most common ophthalmic surgery. To assess patient characteristics and outcomes of contemporary phacoemulsification cataract surgery in a New Zealand public teaching hospital setting. Prospective observational study. Consecutive cases (n = 500) of phacoemulsification surgery between April and June 2015. An independent observer assessed clinical and surgical data preoperatively and 4-6 weeks postoperatively. Visual acuity, intraoperative and postoperative complications. Mean age was 72.3 ± 11.9 years and 57% female. Mean preoperative best-measured visual acuity was 6/30. Ocular comorbidity was present in 45.8% of eyes, most commonly glaucoma (10%), age-related macular degeneration (8%) and diabetic retinopathy (8%). Systemically, hypertension (59%) and diabetes mellitus (31%) were prevalent. Mean contralateral best-measured visual acuity was 6/12 (n = 495) with 62% being phakic. The rate of posterior capsular tear was 2.6% and cystoid macular oedema 3.5%. Intraoperative complication rates were not significantly different between surgeon levels (P = 0.234). However, registrars had fewer postoperative complications than fellows (2.2% vs. 11.9%, P = 0.012). Postoperatively, mean unaided and best-measured visual acuity were 6/12 and 6/9. This study reports current phacoemulsification surgery outcomes in a major public teaching institution. A large proportion of patients exhibited systemic and ocular comorbidities, relatively dense cataracts and poor presenting visual acuity. However, visual outcomes and intraoperative complication rates were not statistically different between trainees and senior surgeons. Generally, outcomes reflect international standards and have improved since the last comparable study in this region.
Publisher: Wiley
Date: 29-10-2012
DOI: 10.1111/J.1442-9071.2012.02877.X
Abstract: Cultured limbal tissue transplants have become widely used over the last decade as a treatment for limbal stem cell deficiency (LSCD). While the number of patients afflicted with LSCD in Australia and New Zealand is considered to be relatively low, the impact of this disease on quality of life is so severe that the potential efficacy of cultured transplants has necessitated investigation. We presently review the basic biology and experimental strategies associated with the use of cultured limbal tissue transplants in Australia and New Zealand. In doing so, we aim to encourage informed discussion on the issues required to advance the use of cultured limbal transplants in Australia and New Zealand. Moreover, we propose that a collaborative network could be established to maintain access to the technology in conjunction with a number of other existing and emerging treatments for eye diseases.
Publisher: Wiley
Date: 25-12-2020
DOI: 10.1111/CEO.13696
Abstract: Reduction of intraoperative complications in phacoemulsification cataract surgery. To assess practicability of a risk stratification system, the New Zealand Cataract Risk Stratification (NZCRS) system, in a major teaching hospital service, without investigator oversight, to ascertain whether benefits identified in research studies are maintained in busy clinical practice. Prospective cohort study in a major public teaching hospital. Five hundred cases of phacoemulsification cataract surgery. NZCRS system inserted into 621 consecutive preoperative cataract patient files. Recommendation to allocate higher-risk cases to experienced surgeons. NZCRS system uptake and adherence, appropriate identification of high risk cases and intraoperative complication rates. NZCRS scores calculated in 500 of 621 (80.5%) cases and 98 (19.6%) scored as "high risk." Cataract surgery (N = 500) performed by: 12 Registrars (20%), 4 Fellows (7.2%), 26 Consultants (72.8%). Risk scores adhered to in 99%. Overall intraoperative complications (3.0%) included iris prolapse 1.6% and posterior capsule tear 0.8%. No statistical difference in complication rates identified between surgeon grades. Mean best-corrected visual acuity was 6/10 (20/32). Postoperatively, cystoid macular oedema occurred in 3.2%. Rescoring by an experienced investigator noted a greater number of "high risk scores" (31.6% vs 19.6%) related to differences in subjective scoring of anterior chamber depth and cataract density. Practical uptake of cataract risk stratification was promising in this study with NZCRS calculated in 80.5% with 99% adherence to scoring recommendations. Compared to baseline studies, in the day-to-day clinical setting, a continued, decreasing trend in frequency and severity of intraoperative complications was noted. Subjective variability of risk scoring may be further improved by better, objective, standardization.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 11-2015
DOI: 10.1016/J.JCRS.2015.10.037
Abstract: We highlight potential problems and pitfalls in cases of Salzmann nodular degeneration by reporting the case of an 84-year-old man with reduced visual acuity due to particularly extensive bilateral Salzmann nodules and moderate cataracts. Large annular Salzmann lesions were removed by superficial keratectomy in each eye. The reproducibility and accuracy of keratometry and biometry improved significantly, and uneventful phacoemulsification cataract surgery was performed 4 weeks after the keratectomy. The phacoemulsification procedures were routine other than the development of pronounced epithelial bullae in the area of Salzmann nodule excision. At final review, the uncorrected distance visual acuity was 20/20 in the right eye and 20/25 in the left eye. No author has a financial or proprietary interest in any material or method mentioned.
Publisher: Wiley
Date: 12-2008
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 04-2014
DOI: 10.1016/J.JCRS.2013.09.014
Abstract: To evaluate the outcomes of transscleral sutured posterior chamber intraocular lens (PC IOL) implantation. Public university hospital, Auckland, New Zealand. Retrospective case series. A modified no-touch transscleral sutured PC IOL implantation technique with a 1-piece monofocal IOL (Alcon CZ70BD) or an aniridia IOL (type 67G, Morcher) was assessed. Seventy-eight cases (80.8% men 53.9% aphakic) were identified. The mean follow-up was 35.5 months and the mean age at surgery, 41 years±21 (SD). The preoperative corrected distance visual acuity (CDVA) was worse than 6/30 in 66.7%. Indications included ocular trauma (46.2%), nontraumatic crystalline lens subluxation (16.7%), post-complicated cataract surgery (10.3%), idiopathic IOL dislocation (10.3%), and congenital cataract/aphakia (10.3%). An aniridia IOL was required in 39.7% of eyes. There were no significant intraoperative complications in 74.4% of eyes. Postoperative complications included transient corneal edema (15.4%), wound leak requiring resuturing (7.7%), retinal detachment (7.7%), and cystoid macular edema (6.4%). One eye (1.3%) developed suture breakage-related late IOL dislocation. Overall, 91.3% of eyes had improved visual acuity or were within 1 line of the presenting CDVA. In eyes with a guarded prognosis, 34.8% achieved a CDVA of 6/12 or better and 43.5% a CDVA of 6/15 to 6/48. In the better prognosis group, 73.9% achieved a CDVA of better than 6/12 and all achieved better than 6/30. Scleral-sutured IOLs achieved good visual outcomes in a public hospital setting. The rate of complications was moderate in this series with a high proportion of severe ocular trauma and a large percentage of aniridia IOLs. No author has a financial or proprietary interest in any material or method mentioned.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 06-2020
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 04-2016
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 02-1999
Publisher: Elsevier BV
Date: 04-2019
Publisher: BMJ
Date: 30-11-2010
Abstract: The corneal dystrophies represent a group of clinically and genetically heterogeneous, inherited diseases, often resulting in bilateral opacification of the cornea, and may require penetrating keratoplasty. Mutations in the transforming growth factor beta-induced (TGFBI) gene segregate with a wide range of phenotypically heterogeneous corneal dystrophies. Many of the other dystrophies remain without molecular characterisation. This study aimed to characterise the molecular basis for corneal disease in a New Zealand population. Nineteen unrelated in iduals affected with a corneal dystrophy (granular, fleck, lattice, posterior polymorphous) and their family members were recruited, a pedigree obtained and their dystrophy extensively phenotyped. After informed consent, s les were taken for DNA extraction. PCR and sequencing of all coding exons of TGFBI was undertaken. All five patients with granular dystrophy had the R555W mutation, and H626P was identified in an intermediate dystrophy of Bowman layer pedigree. No other mutations were detected including in the stromal dystrophy cases. Mutational analysis of TGFBI in a small population has identified sequence changes consistent with previously identified genotype-phenotype correlations. A new genotype-phenotype association was also characterised. No mutations were identified in some in iduals edigrees suggesting greater genetic heterogeneity than is currently known in this group of disorders.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 10-2011
Publisher: Wiley
Date: 12-2006
Publisher: Elsevier BV
Date: 1987
DOI: 10.1016/S0140-6736(87)91908-8
Abstract: Brain water content was measured in tissue s les taken at operation from 19 patients with intrinsic cerebral tumours imaged preoperatively by magnetic resonance. A high correlation (r = 0.94, p less than 0.0001) between white matter water content and the longitudinal relaxation time (T1) enabled water content to be estimated from T1 to within 4%. 11 patients received dexamethasone and improved clinically but their T1, and thus brain water content, was unchanged an average of 6 days later. Intravenous infusion of 20% mannitol in 11 patients significantly reduced T1 in oedematous white matter and tumour within 15 min of administration, and by 30 min the T1 of oedematous white matter had fallen to a mean of 32.4 (SEM 7.1) ms, corresponding to a reduction in water content of 1.4 (0.3)%.
Publisher: Wiley
Date: 04-11-2012
DOI: 10.1111/J.1442-9071.2011.02681.X
Abstract: To investigate the indications for corneal transplantation and the distribution of donor corneal tissue in New Zealand. Analysis of the prospective database of the New Zealand National Eye Bank. A total of 2205 corneal transplants were assessed. New Zealand National Eye Bank records were analysed for the decade 2000-2009. Variables analysed included donor corneal tissue distribution (including public and private sectors), indications for transplantation, donor corneal tissue recipient demographics (age and gender) and corneal transplantation type. An average of 220 corneal transplants were performed each year over the 10-year period (n=2205). The median recipient age was 45years (range 3 to 102years) and 54.0% of recipients were male. In total 71.8% of transplants were performed in the public health sector. Surgeons in the Auckland metropolitan area performed 47.2% of all corneal transplants. The most common indications for corneal transplantation were: keratoconus (41.1%), repeat transplant (17.0%), aphakic seudophakic bullous keratopathy (13.9%), corneal dystrophy (10.7%), keratitis (7.9%) and trauma (3.7%). Overall, penetrating keratoplasty accounted for 90.7% of all corneal transplants, however, during the latter half of the study there was a progressive shift in transplantation type, with deep anterior lamellar keratoplasty and Descemet's stripping endothelial keratoplasty combined accounting for 32.3% of all transplants in the final year of the study period. This New Zealand National Eye Bank study provides valuable data regarding the indications for corneal transplantation, transplant recipient demographics and changes in transplantation type in New Zealand over the past decade.
Publisher: Springer Science and Business Media LLC
Date: 04-2005
Abstract: To compare the intraocular pressure (IOP) measurements obtained using the Pascal dynamic contour tonometer (PDCT) with the standard Goldmann applanation tonometer (GAT) and to correlate these with central corneal thickness (CCT) in patients with normal corneas. A prospective, masked, comparative case series of 116 eyes from patients attending a glaucoma clinic. IOP was measured with PDCT by one examiner and with GAT by a masked, independent examiner. A mean of six CCT readings was used for analysis. IOP measured by the two instruments correlated significantly (r=0.77 P<0.0001). IOP measured by GAT correlated strongly with CCT (r=0.37, P=0.0001) whereas the relationship between IOP measured by PDCT and CCT approached significance (r=0.17, P=0.073). The differences between GAT and PDCT measured IOP also correlated strongly with CCT (r=0.37, P<0.0001). The 95% limits of agreement between GAT and PDCT were +/-4.2 mmHg. Dividing the eyes into three groups on the basis of CCT, demonstrated those in the thickest tertile showed a poorer agreement between instruments and the GAT measured significantly higher IOP in this group (P=0.003) while the PDCT showed no significant differences with different CCTs (P=0.37). Demonstration of the relative independence of PDCT IOP measurements from CCT supports a potential clinical role for this instrument, particularly for subjects with CCT outside the normal range.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 03-2009
DOI: 10.1016/J.JCRS.2008.11.048
Abstract: To characterize and compare the higher-order aberrations (HOAs) in 3 intraocular lenses (IOLs) designed to minimize HOAs using a new physical model eye. Department of Ophthalmology, University of Auckland, New Zealand. Measurements of higher-order wavefront aberrations were obtained using the Zywave aberrometer and a purpose-built physical model eye. The following IOLs were included: AcrySof IQ IOL SN60WF aspheric, Tecnis ZA9003 aspheric, and Adapt Advanced Optics. In idual Zernike modes were compared using analysis of variance (ANOVA). Fifteen assessments were made of each of 36 in idual IOLs (N = 540) at 3 powers (10.0 diopters [D], 20.0 D, 30.0 D), and 18 Zernike modes were compared using multiple ANOVA and canonical discrimination analysis. The 3 IOL models at the 3 powers showed significantly different profiles of HOA. Statistical differences were recorded for 10 of 18 in idual Zernike modes analyzed for an interaction between model and power. The IOLs of the same model appeared to group together in multivariate analysis. Intraocular lenses of a lower power tended to cluster toward the center of the canonical discrimination analysis, while higher-power IOLs were more peripherally located and appeared least similar. Validation experiments using the model eye platform showed high reproducibility and low error. The 3 IOLs had statistically different aberration profiles. Higher-power IOLs had greater differences when analyzed using multivariate techniques. Profiling the HOAs of IOLs may assist in the selection of the most appropriate IOL to maximize visual outcome for a given patient after cataract surgery.
Publisher: Elsevier BV
Date: 07-2013
DOI: 10.1016/J.AJO.2013.01.029
Abstract: To assess the repeatability and comparability of corneal power and central corneal thickness (CCT) measurements obtained using Orbscan II (Bausch & Lomb), Pentacam (Oculus), and Galilei (Ziemer) tomographers. Prospective, comparative study. setting: Departments of Ophthalmology, University of Auckland and Auckland District Health Board, Auckland, New Zealand. study population: Thirty eyes of 30 healthy participants. observations. CCT and corneal power measured using Orbscan II, Pentacam, and Galilei tomography. main outcome measures: Degree of agreement in and repeatability of CCT and corneal power measures. Orbscan II measured significantly lower CCT compared with Pentacam (20 μm P < .0005) and Galilei (18 μm P < .0005). The Orbscan II had wide limits of agreement when compared with both the Galilei (-11 to 47 μm) and Pentacam (-88 to 47 μm). For each device, the intraclass correlation coefficient for CCT was higher than 0.9. The coefficient of variation ranged from 0.33% to 0.93%. There was no significant difference in mean steep keratometry or mean flat keratometry between instrument pairs. However, there was poor agreement in flat keratometry and steep keratometry obtained by Orbscan II compared with those obtained by the Galilei and Pentacam. The keratometry and pachymetry measurements obtained by Orbscan II, Pentcam, and Galilei tomographers were sufficiently disparate that the 3 devices could not be considered equivalent. All 3 devices demonstrated a high level of repeatability, although the Galilei exhibited the best repeatability.
Publisher: Wiley
Date: 22-07-2019
DOI: 10.1111/CEO.13581
Abstract: In New Zealand, repeat keratoplasty has become the second leading indication for corneal transplantation. To report the indications, outcomes and survival of repeat keratoplasty and evaluate the risk factors for graft failure. Retrospective study in a public corneal service. Two hundred nineteen patients undergoing 279 repeat keratoplasty procedures during 1991-2017. The New Zealand National Eye Bank prospectively collects data on all corneal transplants. This was utilized to identify patients undergoing repeat keratoplasty in Auckland. Clinical records were retrospectively reviewed. Graft survival and visual outcome. The repeat keratoplasty technique was penetrating keratoplasty (PK) in 242 cases (86.7%) and endothelial keratoplasty in 37 (13.3%). The most common primary indication was keratoconus (46.6%). The most common indication for repeat keratoplasty was endothelial decompensation (37.6%). For PK performed as a repeat keratoplasty, the median survival in years was 12.0 for first, 3.5 for second and 2.3 for third repeat keratoplasty. Keratoconus had the longest graft survival (median 13.0 years). In surviving grafts, median visual acuity was 6/15 at 1 year and 6/12 at 2 years. On multivariate analysis, regraft number (P = .022), non-European ethnicity (P = .007), concurrent surgical procedure (P < .0005), lower donor endothelial density (P = .028), previous glaucoma surgery (P < .0005), postoperative raised intraocular pressure (P = .001) and graft rejection (P = .032) were associated with keratoplasty failure. Repeat keratoplasty survival is affected by multiple interacting factors and prognosis worsens with each subsequent regraft. These results will help guide clinicians in addressing patients' in idual risk factors when embarking on repeat corneal transplant surgery.
Publisher: Wiley
Date: 31-05-2005
DOI: 10.1111/J.1442-9071.2005.01011.X
Abstract: Advances in molecular genetics and in vivo ocular imaging modalities have enhanced our understanding of the corneal dystrophies. To date at least 11 genes have been identified, in which mutations manifest in corneal disease. In addition there are at least eight other loci identified to which corneal dystrophies have been linked. The information gained from the knowledge of gene function, aberrant protein production, or altered enzyme activity in the cornea, has resulted in greater knowledge of the pathophysiological mechanisms in these disorders. In vivo confocal microscopy has recently enabled microstructural study of dystrophic corneas throughout the disease course, rather than being limited to histopathological analysis of tissue removed at corneal transplantation. This perspective article summarizes the current knowledge, with emphasis on the genes, mutant proteins and resultant mechanisms that lead to manifestations of disease, along with characteristic findings with in vivo confocal microscopy.
Publisher: Wiley
Date: 04-2004
Publisher: Medknow
Date: 2013
Publisher: Wiley
Date: 31-07-2019
DOI: 10.1111/CEO.13589
Publisher: Wiley
Date: 12-2014
DOI: 10.1111/ANS.12871
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 2018
DOI: 10.1016/J.JCRS.2017.10.044
Abstract: To compare the tomography of the corneal epithelium and Bowman layer in eyes with moderate to severe keratoconus before and after epithelial debridement. University hospital tertiary referral center. Prospective case series. Dual-channel Scheimpflug combined with Placido-disk tomography was used to measure the corneal variables in eyes with keratoconus having corneal crosslinking immediately before and after epithelial debridement. The differences in pachymetry, axial keratometry, astigmatism magnitude, asphericity, total corneal power, and spherical aberrations were computed. The study comprised 30 eyes of 30 patients. After epithelial removal, the central (0.0 to 4.0 mm) and midperipheral (4.0 to 7.0 mm) corneal zones were significantly thinner mean (21 μm ± 14 [SD] and 35 ± 44 μm, respectively). The mean anterior axial flat keratometry (K) (+1.71 diopters [D]), steep K (+2.14 D), maximum K (+2.13 D), corneal astigmatism (+1.11 D), asphericity (-0.31), and total corneal power changes (+2.03 D) were significantly different after epithelial debridement. There were no significant changes in posterior corneal flat K or steep K, posterior corneal astigmatism, or posterior asphericity. There were no significant differences in the mean astigmatic axis (anterior or posterior corneal surface) or spherical aberration after epithelial debridement. In eyes with moderate to severe keratoconus, the tomography of Bowman layer was significantly steeper than that of the epithelium thus, epithelial debridement increased the magnitude of anterior corneal keratometry, astigmatism, and prolateness. These data suggest that the corneal epithelium smooths the underlying Bowman layer irregularity in keratoconus.
Publisher: Wiley
Date: 09-2016
DOI: 10.1111/CEO.12813
Abstract: This study aimed to determine the nature and incidence of severe limbal stem cell deficiency (LSCD) in Australia and New Zealand. A 1-year pilot surveillance study with a 1-year follow-up period was conducted in association with the Australian and New Zealand Ophthalmic Surveillance Unit. The study included patients reported by practising ophthalmologists on the Surveillance Unit's database. Ophthalmologists were provided with a definition of severe limbal stem cell deficiency, contacted on a monthly basis by the Unit and asked to report newly diagnosed cases. Severe LSCD was defined as at least 6 clock hours of whorl-like epitheliopathy, an opaque epithelium arising from the limbus, late fluorescein staining of the involved epithelium and superficial corneal neovascularization or conjunctivalization. On average, 286 report cards were sent by the Surveillance Unit to practising ophthalmologists each month (total 3429 over 12 months) and the Unit received an average of 176 responses per month (total 2111 62% response rate). During the 1-year study period from April 2013 to March 2014, 14 positive cases were reported to the Unit. A range of underlying aetiologies were implicated, with contact lens over-wear and cicatrizing conjunctivitis being the most common (n = 3). This surveillance study is the first worldwide to document the incidence of limbal stem cell deficiency however, because of study design limitations, it is likely to have been under-reported. It provides novel data on the demographics, clinical conditions and management of patients with limbal stem cell deficiency as reported by treating ophthalmologists.
Publisher: Public Library of Science (PLoS)
Date: 16-07-2021
DOI: 10.1371/JOURNAL.PONE.0254832
Abstract: To assess the agreement and repeatability of horizontal visible iris diameter (HVID) or white-to-white (WTW) measurements between four imaging modalities combination slit scanning elevation/Placido tomography, infrared biometry, dual rotating scheimpflug camera/Placido tomography, and swept source anterior segment optical coherence tomography (AS-OCT). A prospective study of 35 right eyes of healthy volunteers were evaluated using the Orbscan IIz, IOL Master 700, Galilei G2, and DRI Triton OCT devices. The inter-device agreement and repeatability of HVID/WTW measurements for each device were analysed. Mean HVID/WTW values obtained by the Orbscan IIz, IOL Master 700, Galilei G2 and DRI Triton OCT were 11.77 ± 0.40 mm, 12.40 ± 0.43 mm, 12.25 ± 0.42 mm, and 12.42 ± 0.47 mm, respectively. All pairwise comparisons revealed statistically significant differences in mean HVID/WTW measurements (p = .01) except for the IOL Master 700—DRI OCT Triton pair (p = 0.56). Mean differences showed that the DRI Triton OCT produced the highest HVID/WTW values, followed by the IOL Master 700, Galilei G2 and Orbscan IIz, respectively. The limits of agreement were large on all device pairs. There was high repeatability for all devices (ICC ≥ 0.980). The highest repeatability was seen in the Galilei G2 (ICC = 0.995) and lowest in the Orbscan IIz (ICC = 0.980). The four devices exhibit high repeatability, but should not be used interchangeably for HVID/WTW measurements in clinical practice.
Publisher: Springer Science and Business Media LLC
Date: 06-2016
DOI: 10.1186/S13287-016-0339-7
Abstract: The limbus forms the outer rim of the cornea at the corneoscleral junction and harbours a population of stem cells for corneal maintenance. Injuries to the limbus, through disease or accidents such as chemical injuries or burns, may lead to significant visual impairment due to depletion of the native stem cells of the tissue. Sphere-forming cells were isolated from peripheral cornea for potential use as transplantable elements for limbal stem cell repopulation and limbal reconstruction. Immunocytochemistry, live cell imaging and quantitative PCR were used to characterize spheres and elucidate activity post implantation into human cadaveric corneal tissue. Spheres stained positively for stem cell markers ∆NP63α, ABCG2 and ABCB5 as well as the basal limbal marker and putative niche marker, notch 1. In addition, spheres also stained positively for markers of corneal cells, vimentin, keratin 3, keratocan and laminin, indicating a heterogeneous mix of stromal and epithelial-origin cells. Upon implantation into decellularized corneoscleral tissue, 3D, polarized and radially orientated cell migration with cell proliferation was observed. Cells migrated out from the spheres and repopulated the entire corneal surface over 14 days. Post-implantation analysis revealed qualitative evidence of stem, stromal and epithelial cell markers while quantitative PCR showed a quantitative reduction in keratocan and laminin expression indicative of an enhanced progenitor cell response. Proliferation, quantified by PCNA expression, significantly increased at 4 days subsequently followed by a decrease at day 7 post implantation. These observations suggest great promise for the potential of peripheral corneal spheres as transplantable units for corneal repair, targeting ocular surface regeneration and stem cell repopulation.
Publisher: Wiley
Date: 2007
DOI: 10.1111/J.1442-9071.2007.01416.X
Abstract: To evaluate the Heidelburg Retina Tomograph II (HRTII) retinal module as a tool for grading severity of retinopathy in a diabetic retinal screening and treatment service. Seventy-seven consecutive patients with type 2 diabetes underwent scanning laser tomography using the HRTII. Scan data were analysed using the proprietary macular module software and oedema indices calculated for each of nine topographic macular zones. Two consultant ophthalmologists, masked to the result of the HRTII scans, graded each subject for severity of retinopathy and presence of macular oedema. The oedema indices were analysed statistically to determine whether these correlated with severity of retinopathy and presence of macular oedema. There is an increased oedema index in severe non-proliferative diabetic retinopathy in the outer temporal zone compared with lesser grades of diabetic retinopathy (P = 0.001). In patients with clinically detectable macular oedema, the oedema index from the 500-microm-diameter central zone was significantly higher than those without (P = 0.03). The scanning laser-derived oedema index differentiated between moderate and severe non-proliferative diabetic retinopathy in this series and detected diabetic macular oedema. Further development of this technology may provide an important tool to supplement retinal photographic surveillance in eye clinics overwhelmed by an increasing prevalence of type 2 diabetes.
Publisher: Springer Science and Business Media LLC
Date: 09-1990
DOI: 10.1038/EYE.1990.103
Abstract: The accurate detection and localisation of retained intraocular foreign bodies (IOFB) is important in the planning of subsequent surgical management. Using a porcine eye model, the authors have compared the relative detection rates of real time ultrasonography and plain roentgenograms for a variety of IOFBs. With an overall detection rate of 93%, ultrasonography appears to be a considerably more sensitive investigative tool than plain roentgenograms (40%) for the imaging of IOFBs, particularly those that are non-metallic.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 07-2009
Publisher: Elsevier
Date: 2013
Publisher: Wiley
Date: 07-08-2019
DOI: 10.1111/CEO.13593
Abstract: Retinopathy of prematurity (ROP) is a potentially blinding condition affecting the retinae of premature infants. Effective screening is necessary for timely treatment. The Auckland Regional Telemedicine ROP (ART-ROP) network, utilizes wide-field digital imaging for ROP screening. This study reviews the ART-ROP network. Retrospective analysis of the ART-ROP database. Files of infants in ART-ROP from 2006 to 2015. Data on infant demographics, ROP stage, treatment and outcome was collected. The efficacy of ART-ROP in the management of ROP. A review of 1181 infants across three neonatal intensive care units, was completed. Infants had a mean of four screening sessions with no infants who met ROP screening criteria being missed. Type 1 ROP was present in 83 infants, who had significantly lower average birth weight 786 ± 191 g compared to 1077 ± 285 g (P < .001), and gestational age 25.3 ± 1.7 weeks compared to 27.8 ± 2.2 weeks (P < .001) than the screened cohort. The number of infants requiring screening increased (R ART-ROP solely uses wide-field digital imaging for ROP diagnosis, and management, including discharge, of infants. This detailed review of ART-ROP indicates an increase in screening demand, but a decrease in the rate of type 1 ROP. The ART-ROP telemedicine model demonstrates real potential to address workforce shortage in ROP screening.
Publisher: American Medical Association (AMA)
Date: 03-2014
Publisher: Springer Science and Business Media LLC
Date: 19-08-2023
DOI: 10.1007/S00300-023-03188-8
Abstract: It has been postulated that ultraviolet reflectance is important in mate choice in King Penguins Aptenodytes patagonicus , although not in other penguin species that do not have body parts that reflect UV light. However, this theory has been challenged. Here we aimed to determine the transmission of the ocular media in the large King Penguin as well as the smallest penguin, the Little Penguin Eudyptula minor , and a medium-sized penguin, the Gentoo Penguin Pygoscelis papua , to determine if the penguin eye is capable of seeing ultraviolet light. In all species the cornea absorbed the most damaging rays at 300 nm or below but it was the lens that predominantly determined the transmission of light between 300 and 400 nm. The lenses of a young King Penguin absorbed almost all light less than 370 nm and had 50% transmission at 406 nm, thus ultraviolet perception in the King Penguin is very limited. In contrast, 50% lenticular transmission was 329 nm in the Little Penguin and 367 nm in the Gentoo. Therefore, we suspect that ultraviolet light may be more important in the behaviour of smaller penguins than in the King Penguin, where it is unlikely to play a significant role.
Publisher: Association for Research in Vision and Ophthalmology (ARVO)
Date: 04-08-2015
Publisher: SLACK, Inc.
Date: 2013
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 12-2002
DOI: 10.1016/S0886-3350(02)01494-3
Abstract: To assess the changes in pachymetry after routine corneal and scleral tunnel phacoemulsification. Discipline of Ophthalmology, University of Auckland, Auckland, New Zealand. This prospective study comprised 174 eyes of 174 consecutive patients having uneventful, small-incision, sutureless, phacoemulsification cataract surgery 124 patients had a clear corneal incision and 50, a superior scleral tunnel incision. Difference pachymetry maps were derived from Orbscan II elevation topography data obtained before and 4 weeks after surgery. Corneal thickness changes at 12 midperipheral areas located in 12 meridians were derived from difference (subtraction) maps. The mean corneal thickness within a single area corresponding to the center of the surgical incision was compared to the mean pachymetry readings of all 12 midperipheral measurements. The overall mean midperipheral corneal thickness (12 s les per cornea) increased by a mean of 5.89 microm +/- 16.09 (SD) in the clear corneal incision group and 6.89 +/- 14.50 microm in the scleral tunnel group. The mean central corneal thickness increased by 7.28 +/- 20.98 microm and 7.74 +/- 21.34 microm, respectively. The corneal thickness in the meridian closest to the incision was significantly higher than the mean value of the 12 meridians measured in both groups, with means of 14.95 +/- 26.86 microm in the clear corneal group (P =.001) and 16.22 +/- 21.23 microm in the scleral tunnel group (P =.002). There were no statistically significant postoperative differences in the central, midperipheral, or incision-site corneal thickness measurements between the 2 surgical techniques (P =.77). Time-dependent (fourth-dimensional) pachymetry subtraction maps are useful for following corneal dynamics over time. This study found that small-incision phacoemulsification techniques--scleral and corneal tunnel--had a minor but similar effect on corneal thickness 4 weeks after surgery.
Publisher: Association for Research in Vision and Ophthalmology (ARVO)
Date: 08-2008
DOI: 10.1167/IOVS.08-1951
Abstract: To add to findings in a prior study on the two-dimensional arrangement of the living human sub-basal corneal nerve plexus and determine whether it is a dynamic structure. Laser scanning in vivo confocal microscopy was performed on the left cornea of a healthy subject who had been examined with the same methodology 2 years earlier. Examinations were performed once a week for 6 weeks with the purpose of producing a two-dimensional reconstruction map of the living human sub-basal corneal nerve plexus at each session. A two-dimensional graphics program was used to arrange and map images obtained at each session into confluent montages. The mean dimensions of the corneal areas mapped were 4.80 +/- 0.45 mm horizontally and 4.60 +/- 0.52 mm vertically. The nerve branching patterns observed 2 years earlier did not correspond with those in any recent maps. Over the 6-week period, the sub-basal nerve pattern appeared to migrate centripetally from the corneal periphery toward an inferocentral whorl. In the region of the whorl the nerves altered their generally centripetal direction of migration, undergoing clockwise rotation. The centripetal rate of migration decreased with proximity to the center of the whorl (5.6 +/- 3.4 microm/wk at 13 microm from the whorl, 13.9 +/- 5.5 microm/wk at 333 microm from the whorl, and 25.9 +/- 8.6 microm/wk at 698 microm from the whorl). This study provides strong evidence that the living human sub-basal corneal nerve plexus is a highly dynamic structure, with continuous centripetal movement of identifiable branch points of up to 26 microm/wk, creating dramatic pattern changes in the plexus over a 6-week period.
Publisher: Wiley
Date: 12-2009
DOI: 10.1111/J.1442-9071.2009.02191.X
Abstract: To analyse the pattern of change in publication content and citations generated by a mid-ranking ophthalmology journal as it evolved from the Australian and New Zealand Journal of Ophthalmology (ANZJO) to its successor, Clinical 0mp Experimental Ophthalmology (CEO). The Science Citation Index was used to analyse the publications of ANZJO and CEO over two 10-year periods (1990-1999 and 2000-2009, respectively). Publication and citation patterns were analysed in terms of source authors, institutions and countries. As a secondary measure, journal impact factors (JIFs) were retrieved from the Journal Citation Reports at the end of each period. Over the specified periods, 859 articles published in ANZJO were cited 1210 times, and 1529 articles published in CEO were cited 5374 times. Australia was the largest contributing country to both journals however, the proportional contributions from other countries including New Zealand, UK, USA, India and China increased significantly in CEO. Articles were cited by authors from 793 institutions in 60 countries for ANZJO and 2997 institutions in 95 countries for CEO. The contribution by key authors (identified as the top 10 most-published authors) towards total journal publications was 24% in ANZJO, but only 16% in CEO however, these publications were responsible for 26.6% and 28.8% of the total citations, respectively. With respect to the most recent JIFs, ANZJO was 0.433 in 1999 (ranked 33 of 43 journals) and CEO was 1.35 in 2008 (ranked 27 of 48 journals). CEO has substantially increased the number of publications, citation counts and international sources compared with its well-established predecessor, ANZJO, over the assessed periods. CEO also appears to have a higher international profile with increasing citations counts from more countries. This evolution from a regional, to a more international, journal has been substantial and is reflected by a significant increment in JIF, and a modest increase in overall JIF-ranking, for CEO.
Publisher: Wiley
Date: 07-2011
Publisher: Wiley
Date: 2006
Publisher: Elsevier BV
Date: 02-2013
DOI: 10.1016/J.MEHY.2012.11.006
Abstract: Keratocytes are specialised cells that produce and maintain corneal stromal matrix and play a key role in corneal wound healing. Abnormal functioning of these cells is likely to play a central role in corneal disorders, such as keratoconus, which in many cases leads to corneal blindness if untreated. The genetic basis of keratoconus is poorly understood but it is likely that apoptosis pathways are involved. The current paper proposes a novel hypothesis for the treatment and prevention of corneal blindness in disorders such as keratoconus as an alternative to the gold standard treatment of penetrating or partial thickness keratoplasty. The proposed hypothesis involves the isolation, purification and transplantation of keratocyte progenitor cells (KPC), with introduction into stroma via femtosecond laser channels in diseased corneal stroma using a carrier medium. The success of this approach will depend upon the viability, migration, and cell ision of introduced KPC and production of normal stromal matrix. Results from previous studies suggest that cellular transplantation is possible and may lead to healthy stromal matrix production and remission of a disease phenotype in patients affected with disorders such as keratoconus. If the current hypothesis proves to be correct, it may offer an alternative to invasive keratoplasty for treatment of corneal disorders such as keratoconus that cause significant morbidity for millions of people worldwide.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 12-2002
DOI: 10.1016/S0886-3350(02)01504-3
Abstract: To establish the accuracy of Orbscan II (Orbtek Inc.) slit-scanning elevation topography in analyzing the anterior surface of complex test objects. Discipline of Ophthalmology, University of Auckland, Faculty of Medical and Health Sciences, Auckland, New Zealand. Six test objects were created from 2 materials: standard calibration poly(methyl methacrylate) (PMMA) (Orbtek Inc.) and a research PMMA material. The test objects were produced with spherical (radii of curvature 6.00 mm, 7.67 mm, and 8.88 mm), aspherical (apical radius 7.67, eccentricity 0.5, Q -0.25), and toroidal (7.67/7.92 mm radii of curvature) surfaces. The accuracy of the test surfaces was established by Form Talysurf Analysis. A single calibrated Orbscan II device was used to obtain 20 separate anterior elevation maps of each test object. The data obtained from Orbscan II, at 0.2 mm intervals along the chosen meridian, were directly compared with the Talysurf values for each test surface. Orbscan II measurements of all test objects were statistically significantly different from the Talysurf values (P <.001). The test objects produced from standard calibration material were more accurately measured by Orbscan II than the objects produced from the research material. Data obtained by Orbscan II from the central 3.5 mm of all test objects were more accurate than peripheral data when compared with the Talysurf values (P =.001). Orbscan II anterior surface elevation measurements differed significantly from Form Talysurf Analysis of complex test surfaces. However, the magnitude of the errors in the measurement of standard test objects was small, less than 0.20 microm centrally and 0.70 microm peripherally. Clinically, if similar accuracy of measurement is confirmed in the human eye, anterior surface elevation maps can be considered accurate representations of corneal shape.
Publisher: Research Square Platform LLC
Date: 19-12-2022
DOI: 10.21203/RS.3.RS-2316874/V1
Abstract: Objective To determine the repeatability limits of corneal tomography parameters in patients with advanced and moderately thin keratoconic corneas to assist in planning thickness-based procedural interventions. Methods Prospective, single-centre, repeatability study. Three tomography scans using the Pentacam AXL were obtained from patients with keratoconus with thinnest corneal thickness TCT ≦ 400 µm (sub-400 group) and compared to those with TCT = 450–500 µm (450-plus group). Eyes with previous crosslinking, intraocular surgery, or acute corneal hydrops were excluded. Eyes were age and gender-matched. The within-subject standard deviations for flat keratometry (K1), steep keratometry (K2), maximal keratometry (K max ), astigmatism and TCT were used to calculate respective repeatability limits (r). Intra-class correlation coefficients (ICC) were also analysed. Results The sub-400 group comprised 114 eyes from 114 participants, and the 450-plus group comprised 114 eyes from 114 participants. In the sub-400 group, TCT was amongst the least repeatable parameters (33.92 µm ICC 0.96), compared with the 450-plus group (14.32 µm ICC 0.99, p 0.01). In the sub-400 group, K1 and K2 of the anterior surface were the most repeatable parameters (r 3.79 and 3.22 respectively ICC 0.97 and 0.98 respectively) compared with the 450-plus group (r 1.17 and 0.92 respectively and ICC 0.98 and 0.99 respectively, p 0.01). Conclusions The repeatability of corneal tomography measurements is significantly reduced in sub-400 keratoconic corneas when compared to 450-plus corneas. Consideration to repeatability limits should be carefully considered when surgical interventions are planned for such patients.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 04-2000
DOI: 10.1016/S0886-3350(00)00324-2
Abstract: To analyze the efficacy of a standardized paired arcuate incision and augmentation suture technique in the treatment of various levels of post-penetrating keratoplasty (PKP) astigmatism. Lions Eye Institute, Royal Perth Hospital, Perth, Australia, and University of Dundee Department of Ophthalmology, Dundee, United Kingdom.A standardized paired arcuate incision and paired augmentation suture technique was used to treat 34 eyes with post-PKP astigmatism ranging from -3.50 to -20.00 diopters (D) at the spectacle plane. The technique consisted of paired arcuate incisions of 3 clock hours, 480 microm deep in the graft-host junction, and 2 pairs of augmentation 10-0 nylon sutures. The mean preoperative cylinder was -9.14 D +/- 4.38 (SD) and the mean postoperative cylinder, -3.59 +/- 1.92 D at the corneal plane after a mean follow-up of 50 +/- 43 weeks. This represents an empirical reduction in mean cylinder of 5. 55 D (60.7%). The Alpins correction index (surgically induced astigmatism [SIA] ided by target induced astigmatism) was calculated for each case, and the mean was 1.01 +/- 0.34, with a median of 0.91. Approximately 53.1% of cases achieved a correction index between 0.80 and 1.20, and the correction index correlated poorly with the initial magnitude of cylinder. A direct numerical relationship between SIA and the initial magnitude of cylinder was observed, although a standard surgical procedure was used in all cases.A simple standardized technique using paired arcuate incisions in the graft-host junction with paired augmentation sutures reduces the amount of cylinder in proportion to the magnitude of the preoperative cylinder and effectively reduces post-PKP astigmatism.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 02-2006
Publisher: Elsevier BV
Date: 2012
DOI: 10.1016/J.MEDENGPHY.2011.06.015
Abstract: In this paper we investigate blood flow in the ophthalmic artery (OA) which is the major artery supplying blood to the eyes. An OA and several other cerebral arteries are digitized from a computed tomography angiography (CTA) image of an aneurysm patient. Utilizing a reduced version (1D) of the governing Navier-Stokes equations we solve the transient flow in these arteries. The flow waveform of the patient-OA is compared with that in a healthy vascular tree, and also with published ultrasonic measurements. We found that hyperemia rather than ischemia occurred in the OA, and we suggest that this was unlikely to be the cause of impaired vision in the patient. A more likely explanation is the compression of the optic nerves caused by the mass of the aneurysm.
Publisher: Wiley
Date: 10-2001
DOI: 10.1046/J.1442-9071.2001.00434.X
Abstract: To analyse and describe three cases of rare corneal dystrophy and highlight their in vivo microstructural features. Subject 1 was diagnosed with a posterior stromal fleck corneal dystrophy Two of her three children were also affected. Subjects 2 and 3 exhibited an almost identical clinical appearance on biomicroscopic examination, such that both clinically were diagnosed as having pre-Descemet's dystrophies. All subjects underwent in vivo confocal microscopy and approximately 300 sequential digital images were obtained and analysed for each cornea. In vivo confocal microscopy of subject 1 demonstrated an abnormal appearance of numerous large ovoid particles, measuring 50-70 microm in diameter in the mid and posterior stroma as well as smaller hyperreflective dot-like intracellular deposits, of less than 1 microm diameter. Despite the near-identical clinical appearance, subjects 2 and 3 could be clearly differentiated by in vivo confocal microscopy. Subject 2 exhibited small, irregular, optically dense particles, mainly in the anterior stroma, whereas subject 3 possessed classical involvement of the stroma immediately adjacent to Descemet's membrane, with numerous regular small, hyperreflective particles. The ability of in vivo confocal microscopy to localize and accurately measure various elements in different corneal layers may help to resolve whether abnormalities are intra- or extracellular, and aid clearer differentiation of rare corneal disorders.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 04-2000
DOI: 10.1016/S0886-3350(00)00312-6
Abstract: To identify factors that motivate patients to seek laser in situ keratomileusis (LASIK) treatment for myopia and establish subjective levels of functional improvement and satisfaction across a range of indices after LASIK surgery. The Corneal Diseases and Excimer Laser Research Unit, University of Dundee, Ninewells Hospital and Medical School, Dundee, Scotland. In this questionnaire-based, cross-sectional study, an anonymous 34-item questionnaire was forwarded to 50 consecutive patients in a prospective study who had had LASIK for high myopia by a single surgeon at a single center. The questionnaire used visual analog scales, anchored at each end by an adjectival descriptor. The mean preoperative myopia was -10.7 diopters +/- 4.4 (SD). Seventy-six percent of eyes (83% of patients) achieved post-LASIK uncorrected visual acuity (UCVA) of 6/12 or better 1 eye lost 2 lines of corrected Snellen visual acuity. A 98% reply rate was achieved. The most common motivating factor for pursuing LASIK was to improve UCVA (88%) only 21% rated improved cosmesis as an important motive. Most patients (81% to 100%) reported functional improvement across the spectrum of visual tasks assessed, although 8.8% reported difficulty with nighttime driving. Ninety-six percent felt their UCVA was as good as anticipated, 97.9% were satisfied with the speed of visual improvement, 93.8% achieved the goals for which they had surgery, 97.9% reported an improved quality of life, and 97.9% were satisfied with the overall outcome of LASIK. Using an anonymous, wide-ranging questionnaire, high levels of functional improvement and satisfaction with the speed of visual recovery and outcome were reported by patients after LASIK for high myopia. Nighttime driving symptoms of variable severity were, however, noted by 8.8% of patients, despite high levels of satisfaction with other aspects of visual function.
Publisher: BMJ
Date: 02-2002
DOI: 10.1136/BJO.86.2.185
Abstract: To prospectively assess cataract surgery in a major New Zealand public hospital by defining presenting clinical parameters and surgical and clinical outcomes in a cohort of subjects just below threshold for treatment, based upon a points based prioritisation system. The prospective observational study comprised 488 eyes of 480 subjects undergoing consecutive cataract operations at Auckland Hospital. All subjects underwent extensive ophthalmic examination before and after surgery. Details of the surgical procedure, including any intraoperative difficulties or complications, were documented. Postoperative review was performed at 1 day and 4 weeks after surgery. Demographic data, clinical outcomes, and adverse events were correlated by an independent assessor. The mean age at surgery was 74.9 (SD 9.6) years with a female predominance (62%). Significant systemic disease affected 80% of subjects, with 20% of the overall cohort exhibiting diabetes mellitus. 26% of eyes exhibited coexisting ocular disease and in 7.6% this affected best spectacle corrected visual acuity (BSCVA). A mean spherical equivalent of -0.49 (1.03) D and mean BSCVA of 0.9 (0.6) log MAR units (Snellen equivalent approximately 6/48) was noted preoperatively. Local anaesthesia was employed in 99.8% of subjects (94.9% sub-Tenon's). The majority of procedures (97.3%) were small incision phacoemulsification with foldable lens implant. Complications included: 4.9% posterior capsule tears, 3.8% cystoid macular oedema, and one case (0.2%) of endophthalmitis. Mean BSCVA after surgery was 0.1 (0.2) log MAR units (6/7.5 Snellen equivalent), with a mean spherical equivalent of -0.46 (0.89) D, and was 6/12 or better in 88% of all eyes. A drop in BSCVA, thought to be directly attributable to the surgical intervention, was recorded in a small percentage of eyes (1.5%) after surgery. This study provides a representative assessment of the management of cataract in the New Zealand public hospital system. A predominantly elderly, female population, frequently exhibiting significant systemic illness and coexisting ocular disease, relatively advanced cataracts, and poor BSCVA, presented for cataract surgery. The majority of subjects underwent small incision, phacoemulsification, day case surgery. While almost 90% achieved at least 6/12 BSCVA post-surgery, approximately 5% sustained an adverse intraoperative event and 1.5% of eyes exhibited a reduction in BSCVA postoperatively.
Publisher: Elsevier BV
Date: 02-2014
DOI: 10.1016/J.OPHTHA.2013.09.014
Abstract: To use in vivo confocal microscopy (IVCM) to quantitatively analyze microstructural changes over time, after corneal collagen cross-linking for keratoconus. Prospective cohort study. A total of 38 eyes of 38 patients undergoing collagen cross-linking for keratoconus. Prospective, clinical cohort study of corneal collagen cross-linking in progressive keratoconus. Laser scanning IVCM performed preoperatively and at 1, 3, 6, and 12 months postoperatively. Density of corneal sub-basal nerves, anterior and posterior keratocytes, and corneal endothelium. Compared with baseline values, the mean sub-basal nerve density decreased significantly at 1, 3, and 6 months postoperatively (P < 0.01) however, this returned to preoperative values at 12 months (P = 0.57). One month postoperatively, there was complete absence of keratocyte nuclei in 86% of corneas. Anterior stromal edema with hyper-reflective cytoplasm and extracellular lacunae in a honeycomb-like appearance was observed and persisted at 3 months postoperatively. Scattered, presumed fragmented keratocyte nuclei, were observed at 1 and 3 months, but by 6 months, keratocyte repopulation of the anterior stroma was apparent. Quantitative analysis confirmed a significant decrease in the mean anterior keratocyte density 1, 3, and 6 months postoperatively (P ≤ 0.01) with return to baseline values at 12 months postoperatively (P = 0.57). The demarcation between treated and untreated corneal stroma appeared as a region where normal keratocytes transitioned into elongated, hyper-reflective, needle-like structures and then into large hyper-reflective stromal bands. There was no significant change in posterior keratocyte density or endothelial density at any postoperative time point. This prospective IVCM study revealed complete loss of the sub-basal nerve plexus and loss of anterior stromal keratocytes in the early postoperative period, with complete regeneration of the sub-basal nerve plexus and keratocyte repopulation by 12 months postoperatively. The posterior stroma and corneal endothelium were unaffected.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 07-2005
DOI: 10.1097/01.ICO.0000153557.59407.20
Abstract: This study was designed to delineate the morphologic features of posterior polymorphous dystrophy (PPD) using in vivo confocal microscopy. Six patients with clinically diagnosed PPD were examined by slit-l biomicroscopy, Orbscan II slit-scanning elevation topography, and in vivo confocal microscopy. Endothelial cell densities ranged from 613 to 3,405 cells/mm and endothelial polymegathism was noted in all cases, whereas endothelial pleomorphism was not a prominent feature. Three cases exhibited bright endothelial nuclei. A variety of abnormal curvilinear and vesicular abnormalities were imaged by in vivo confocal microscopy, with lesions ranging between 6 and 159 microm in diameter. Abnormal endothelial cells were visible within some of these lesions. Six cases showed hyperreflectivity at the level of Descemet's membrane around the lesions. Deep stromal keratocytes appeared to aggregate around, or were compressed by, the endothelial lesions in one case. We report the largest case series of PPD imaged by in vivo confocal microscopy. The ability of in vivo confocal microscopy to assess the living cornea over time enables monitoring of disease progression and thus the potential to identify and correlate development of, or changes in, microstructural features. As more data become available, these analyses may enable the formulation of prognostic and diagnostic criteria.
Publisher: Wiley
Date: 27-11-2003
DOI: 10.1046/J.1442-9071.2003.00708.X
Abstract: To obtain an overview of the treatment of infectious diseases of the cornea by New Zealand ophthalmologists and to analyse the data in the context of evidence-based treatment recommendations. A questionnaire was sent to all New Zealand ophthalmologists. It comprised 23 multiple-choice questions pertaining to the characteristics of the respondents, the nature of their practice and their prescribing preferences in infectious conjunctivitis and keratitis. Of the 93 ophthalmologists surveyed, 80.6% returned the questionnaire. Of those in clinical practice, 91.4% regularly treated patients with corneal disease. A subspecialty interest in cornea was stated by 12.5% of these. This paper reports observations for adenoviral conjunctivitis and adenoviral, Herpes simplex, varicella zoster, bacterial, acanthamoebal and fungal keratitis. In some conditions prescribing practice varied dramatically, such as in adenoviral conjunctivitis where 50% of respondents prescribed a corticosteroid and 51.6% an antibiotic, whereas 37.5% prescribed only lubrication or no topical treatment. In other conditions there was a high degree of agreement between ophthalmologists indeed, all ophthalmologists treated Herpes simplex dendritic keratitis with topical acyclovir. No statistically significant differences in prescribing habits were identified between subspecialist and non-subspecialist groups, although some important clinical differences emerged. There were occasional marked differences in response when the age group of respondents was considered, particularly in relation to the management of adenoviral infections and bacterial keratitis. The findings of this survey suggest that the majority of New Zealand ophthalmologists generally follow international guidelines for the management of infectious keratitis. The identified variations in management provide a foundation for informed clinical debate and the development of treatment guidelines, in line with evidence-based recommendations.
Publisher: Wiley
Date: 30-01-2007
DOI: 10.1111/J.1442-9071.2006.01414.X
Abstract: Despite established international guidelines on preferred teaching components for ophthalmology in undergraduate curricula, with increasingly less specialty-based undergraduate teaching within curricula, teaching of core ophthalmology knowledge and skills may become marginalized. This survey aims to evaluate the current state of undergraduate ophthalmology teaching in Australasia and proximate Asian medical schools. A questionnaire was developed to determine the content and extent of ophthalmology teaching in the undergraduate medical curriculum. The questionnaire was sent to 25 medical schools throughout Australasia and Asia. Nineteen of the 25 questionnaires were returned (76% response rate). Ophthalmology teaching programmes ranged from 2 to 20 days: five (26%) medical schools having one ophthalmology attachment six schools (32%) two attachments and the remainder three or more. Only seven of the schools taught all 13 ophthalmology topics recommended in current curriculum guidelines. Ocular examination (100%), lens and cataract (95%) and ocular manifestations of systemic disease (95%) were the most commonly taught topics, with intraocular tumours only covered by 10 schools (53%). Students in 14 schools (74%) attended ophthalmology operating theatre, but only two schools (11%) offered attendance at optometry clinics. Ten schools (53%) required a pass in ophthalmology to complete the academic year. Ophthalmology may increasingly be a small, or even absent, component of undergraduate medical curricula. Despite established international ophthalmology curriculum guidelines, this survey highlights significant lack of uniformity in their implementation.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 10-2011
Publisher: Wiley
Date: 04-2014
DOI: 10.1111/CEO.12155
Publisher: Wiley
Date: 16-03-2016
DOI: 10.1111/CEO.12712
Publisher: Springer Science and Business Media LLC
Date: 04-09-2014
DOI: 10.1007/S00198-014-2872-5
Abstract: This prospective study showed that the incidence of acute anterior uveitis, confirmed by ophthalmic examination, in patients receiving intravenous zoledronate infusions as part of a randomized controlled trial for fracture prevention is 1.1%. We prospectively investigated the incidence of ocular side effects after a single intravenous zoledronate infusion. In a secondary analysis of a double-blind, placebo-controlled trial in which early post-menopausal women (N=1054) with normal bone density or osteopenia were randomized to infusion of zoledronate 5 mg (N=703) or placebo (N=351), we analyzed significant adverse ocular events occurring within 3 months. Fourteen participants reported ocular symptoms after the infusion. All were examined by an ophthalmologist and eight were diagnosed with acute anterior uveitis (AAU) and one with sectoral episcleritis. The incidence of AAU and episcleritis was 1.1% (95% CI 0.5-2.1) and 0.1% (95% CI 0.0-0.7), respectively, in the zoledronate group and 0% for both conditions in the placebo group (95% CI 0.0-0.8). The mean time from infusion to symptom onset for AAU was 3 days (range 2-4). Three cases were bilateral. AAU was mild-moderate in seven participants and severe in one. All affected eyes were treated with topical cyclopentolate 1% (to break, or minimize, posterior synechiae), and intensive, potent, topical corticosteroids with a tapering regime based on treatment response. The mean duration of topical corticosteroid was 26±10 days (range 17-44). The mean, best corrected visual acuity was 20/20 (range 20/20-20/40) at presentation, which remained unchanged after AAU resolution. None of the participants lost vision, and no long-term sequelae were reported at last follow-up (range 3-13 months post-infusion). Prescribers should inform patients about the possibility of ocular side effects with zoledronate infusions and refer promptly to an ophthalmologist if symptoms develop.
Publisher: Wiley
Date: 22-01-2018
DOI: 10.1111/CEO.13125
Publisher: Wiley
Date: 06-2004
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 06-2013
Publisher: Wiley
Date: 02-2004
DOI: 10.1046/J.1442-9071.2004.00762.X
Abstract: Arthur Thomas Paterson was a pre-eminent New Zealand ophthalmologist who settled in the United Kingdom after the First World War and became a leading figure in the development of ophthalmic services in the north-east of England. This vignette explores his contributions to clinical education and the establishment of comprehensive ophthalmic services in Newcastle upon Tyne. It also highlights the Arthur Thomas Paterson scholarship bequest to enable New Zealand ophthalmologists to acquire additional specialist training in inter-national centres of excellence.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 07-06-2020
Publisher: Wiley
Date: 12-2005
Publisher: Edward Elgar Publishing
Date: 28-05-2003
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 06-2019
DOI: 10.1016/J.JCRS.2019.01.003
Abstract: To examine the outcomes of phacoemulsification cataract surgery in eyes with herpes zoster-related keratitis and/or uveitis and evaluate the risks for recurrent disease. Public ophthalmology service, Auckland, New Zealand. Retrospective case series. Patients with herpes zoster-related keratitis and/or uveitis who had cataract surgery in the ipsilateral eye were reviewed. Outcome measures were intraoperative and postoperative complications, postoperative visual acuity, and recurrent disease. Fifty-seven eyes of 57 patients were included. Thirty-eight patients (66.7%) had recurrent disease before cataract surgery. Intraoperative complications occurred in 8 patients (14.0%) and included posterior capsule tear in 2 patients (3.5%). Postoperative complications included intraocular pressure of 30 mm Hg or higher in 2 patients (3.5%) and central corneal edema in 8 patients (14.0%) all resolved by 1 month. Cystoid macular edema occurred in 2 patients (3.5%). The median corrected distance visual acuity at 12 months was 20/40 (interquartile range, 20/30-20/50). Corneal scarring was associated with poorer vision (P = .003). Herpes zoster recurred in 23 patients (40.4%) after surgery. An increased risk for recurrence was associated with shorter periods of quiescence (P = .029) and greater number of recurrences before surgery (P = .039). One eye was eviscerated because of the severity of the disease. Phacoemulsification in eyes with previous herpes zoster-related keratitis or uveitis posed a mildly increased risk for intraoperative and postoperative complications however, herpes zoster disease recurrence after surgery was common and was severe in some cases. Consideration should be given to maximizing the period of quiescence before surgery and the potential role of antiviral prophylaxis.
Publisher: Wiley
Date: 24-05-2017
DOI: 10.1111/CEO.12959
Publisher: Elsevier BV
Date: 06-2018
Publisher: Springer Science and Business Media LLC
Date: 03-01-2019
DOI: 10.1007/S40291-018-0379-Z
Abstract: Fuchs' endothelial corneal dystrophy (FECD) is a common disease resulting from corneal endothelial cell dysfunction. It is inherited in an autosomal dominant fashion with incomplete penetrance, and with a female bias. Approximately half of cases occur sporadically, and the remainder are familial. Early and late-onset forms of the disease exist. A review of the literature has revealed more than 15 genes harbouring mutations and/or single nucleotide polymorphisms associated with FECD. The proteins encoded by these genes cover a wide range of endothelial function, including transcription regulation, DNA repair, mitochondrial DNA mutations, targeting of proteins to the cell membrane, deglutamylation of proteins, extracellular matrix secretion, formation of cell-cell and cell-extracellular matrix junctions, water pump, and apoptosis. These genetic variations will form the platform for the further understanding of the pathological basis of the disease, and the development of targeted treatments. This review aims to summarise known genetic variations associated with FECD, discuss any known molecular effects of the variations, how these provide opportunities for targeted therapies, and what therapies are currently in development.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 07-2011
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 08-2004
Publisher: Informa UK Limited
Date: 03-2013
DOI: 10.1111/CXO.12050
Abstract: The majority of those with keratoconus can maximise visual acuity with spectacle or contact lens correction as they age however, as subjects enter their sixties, cataracts may supervene and contact lens tolerance diminishes with consequent reduction in visual acuity. Following cataract extraction, the complex refractive error associated with keratoconus may not be readily corrected by an intraocular lens alone. This report highlights the planned implantation of a primary posterior chamber toric intraocular lens with a secondary piggyback, sulcus-based, intraocular lens in advanced but stable keratoconus with extreme myopic astigmatism and cataract.
Publisher: Association for Research in Vision and Ophthalmology (ARVO)
Date: 13-06-2014
Abstract: To examine the repeatability of measurements obtained using a noncontact Scheimpflug-based tonometer (Corvis ST) and investigate potential differences in these parameters between healthy and keratoconic (KC) corneas. Forty-five keratoconic eyes and 103 healthy eyes were examined using biomicroscopy, corneal tomography and the Corvis ST (CST). Intraocular pressure and central corneal thickness (CCT) were highly repeatable (intraclass correlation [ICC] > 0.70, coefficient of variation [CV] 0.60, CV < 0.20). There was no association between DA and age, sex, or ethnicity in healthy eyes. There was a greater mean DA in the KC group compared with 46 age-matched healthy eyes (KC 1.37 ± 0.21 mm, healthy 1.05 ± 0.11 mm, P < 0.001). Multivariate analysis showed DA in KC was predicted by IOP, CCT, and the steepest simulated keratometry value (P = 0.03, P = 0.03, P = 0.001 respectively, R(2) = 0.75). A subgroup analysis of healthy and KC eyes with comparable mean CCT and IOP highlighted a statistically significant difference in mean DA (KC 1.25 ± 0.08 mm, thin healthy 1.13 ± 0.09 mm, P = 0.006). Receiver-operating characteristic analysis showed an area under the curve of 0.77 (95% CI 0.61-0.93, P = 0.006) but no ideal cutoff value for DA. Key parameters assessed by the CST are repeatable. Keratoconus is associated with greater DA than in healthy eyes, even when controlled for CCT and IOP. Deformation litude may be a useful adjunct in keratoconus assessment and monitoring, but cannot solely discriminate between healthy and keratoconic corneas.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 08-2020
Publisher: Wiley
Date: 15-05-2017
DOI: 10.1111/CEO.12965
Abstract: This study aims to describe patient demographics, visual and surgical outcomes of a cohort undergoing small incision cataract surgery at a Pacific regional ophthalmic training facility. This is a prospective, longitudinal study conducted at the Pacific Eye Institute, Fiji. One hundred fifty-six patients underwent small incision cataract surgery. Preoperatively, a complete ophthalmic examination, including pachymetry and macular optical coherence tomography performed by two independent investigators. Temporal small incision cataract surgery with intraocular lens insertion was performed by ophthalmologists, and trainee ophthalmologists. Follow-up occurred at day one, four weeks and 3 months. Patient characteristics, visual outcomes including surgically induced astigmatism and complications. Ninety-one per cent (142/156) attended 3-month follow-up with median age 63 years (range 19-82), 52% female (81/156) and 58% (90/156) Fijian ethnicity. In 37% (57/156), the contralateral eye was pseudophakic. Mean preoperative best spectacle-corrected visual acuity was logMAR 1.44 (6/165). At 3 months, 74% (105/142) achieved ≥6/18 unaided vision (94% [133/142] best spectacle-corrected visual acuity). Mean postoperative spherical equivalent was -0.78 (SD 0.95) D and mean surgically induced astigmatism 1.04 (0.57) D. Complications included posterior capsular rupture with vitreous loss (4% [6/156]), optical coherence tomography confirmed macular oedema (8% [12/152] at 4 weeks), significant posterior capsular opacity (23% [31/136]) and >5% increase in preoperative pachymetry (1% [1/142]) at 3 months. Reduction in preoperative best spectacle-corrected visual acuity occurred in 2% (3/142). No cases of endophthalmitis. Small incision cataract surgery provided to a regional population is effective with 94% achieving the World Health Organisation's definition of 'Good Vision' (≥6/18). Refinements in biometric and surgical techniques may allow a greater proportion of patients to achieve good unaided vision.
Publisher: Wiley
Date: 13-07-2020
DOI: 10.1111/CEO.13813
Publisher: Wiley
Date: 04-2005
DOI: 10.1111/J.1442-9071.2005.00975.X
Abstract: To establish a relationship between the forward protrusion of the cornea (keratectasia), following successful LASIK, and anterior chamber depth. One hundred and fifteen eyes of 59 patients who had undergone Zyoptix LASIK and 39 eyes of 21 patients who had undergone PlanoScan LASIK at the Eye Institute, Centre for Refractive Surgery, Remuera, Auckland, New Zealand, were included in the study. The results of Orbscan II acquisitions, taken before and 8.3 weeks +/- 4.0 (mean +/- standard deviation) following the procedure, were analysed to determine the amount of forward protrusion of the central 2 mm diameter of the posterior surface. The apparent keratectasia was then related to the Orbscan II anterior chamber depth (ACD) measurement in a linear mixed model analysis that included 'right or left eye', 'sex', 'type of LASIK procedure', 'change in pachymetry', 'postoperative pachymetry', 'change in anterior corneal curvature', 'postoperative anterior corneal curvature', 'planned ablation depth' and 'time until follow-up' as factors and covariates. The mean +/- SD amount of keratectasia determined by Orbscan II was 22.8 +/- 26.8 microm for the Zyoptix group and 16.9 +/- 24.6 microm for the PlanoScan group. The reduction in depth of the anterior chamber was 14.7 +/- 79.3 microm for the Zyoptix group and 18.2 +/- 68.8 microm for the PlanoScan group. The mixed model analysis demonstrated strong relationships with postoperative pachymetry and change in anterior corneal curvature (P < 0.001 and P < 0.001, respectively). Furthermore, the statistical model showed a marked significant difference in the Orbscan II assessment of keratectasia and change in ACD (P < 0.001). Using the Orbscan II device, the forward protrusion of the posterior corneal surface appears to coincide with a paradoxical reduction in depth of the anterior chamber. Although the keratectasia found in this study is accompanied by thin postoperative corneas and larger central pachymetry change, the contradictory decrease in anterior chamber depth creates uncertainty of measurement, and of ectasia as a mechanism of regression.
Publisher: BMJ
Date: 02-2000
DOI: 10.1136/BJO.84.2.229
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 04-2001
DOI: 10.1016/S0886-3350(01)00765-9
Abstract: To evaluate the safety and predictability of laser in situ keratomileusis (LASIK) retreatment following primary procedures for high myopia and astigmatism. Corneal Diseases and Excimer Laser Research Unit, Department of Ophthalmology, University of Dundee, Dundee, United Kingdom. This prospective observational study of retreatment comprised a cohort of 109 eyes having primary LASIK for high myopia and astigmatism with a spherical equivalent (SE) of -9.70 diopters (D) +/- 4.06 (SD). Twenty-four eyes (22%) with an initial myopic SE of -9.83 +/- 3.50 D, a comparable subset of the entire group (P /=6 months, 13 eyes > or = 12 months). The mean myopic SE was reduced to +0.53 +/- 0.62 D at 1 week, +0.05 +/- 0.50 D at 1 month, +0.30 +/- 0.50 D at 6 months, and +0.18 +/- 0.42 D at the latest follow-up, 12.8 months. At the latest review, 62% of eyes were within +/-0.50 D of emmetropia and 100% were within +/-1.00 D. The mean refraction did not alter statistically between 1 week and subsequent times. The mean UCVA improved from 6/30 prior to retreatment to 6/9 at the latest follow-up. Uncorrected visual acuity of 6/6 or better, 6/9 or better, and 6/12 or better was achieved by 33.0%, 75.0%, and 95.8% of eyes, respectively. No significant complications that led to a loss of best corrected visual acuity were encountered, although retreatment procedures were more uncomfortable than primary procedures and self-limiting epithelial ingrowth that did not threaten vision was common, and 2 patients complained of nighttime visual symptoms. Retreatment of residual myopia by reelevating the flap was relatively safe and predictable, with a low risk of sight-threatening complications. However, longer term studies may be required to detect late complications.
Publisher: Wiley
Date: 11-2010
Publisher: Wiley
Date: 12-2016
DOI: 10.1111/CEO.12848
Publisher: Association for Research in Vision and Ophthalmology (ARVO)
Date: 02-03-2012
DOI: 10.1167/IOVS.11-8711
Abstract: Gap junctions play a major role in corneal wound healing. This study used reproducible models of corneal wound healing to evaluate the effect of a gap junction channel modulator, connexin43 (Cx43) antisense oligodeoxynucleotides (AsODN), on corneal healing dynamics. A mechanical scrape wound model was used to evaluate Cx43 AsODN penetration and initial wound reepithelialization 12 hours postsurgery. Thereafter, detailed analyses of corneal edema, inflammation, and healing were performed in an excimer laser surface ablation model. In vivo confocal microscopy determined clinical parameters (edema, haze) and cellular changes (stromal hypercellularity, reepithelialization), whereas histology and immunohistochemistry were used to quantify stromal edema, inflammation, and reepithelialization. Cx43 AsODN penetrated through the hydrophilic stroma where the epithelium had been removed and accumulated in the basal epithelium close to the wound edge. Twelve hours after scrape wounding, Cx43 AsODN-treated eyes showed a significant reduction in wound area compared with the vehicle alone (1.59±0.37 and 2.29±0.58 mm2, respectively, P<0.01). After excimer laser ablation, stromal edema and inflammation were reduced, with endothelial structures being clearly visible, and reepithelialization rates were again increased in Cx43 AsODN-treated eyes. Histologic analysis confirmed reduced edema in the central wound site and at the periphery of treated corneas (P<0.05), whereas immunohistochemistry showed lower Cx43 levels (P<0.05), reduced myofibroblast activation, and improved epithelial basal lamina deposition in antisense-treated wounds (P<0.01). Application of Cx43 AsODN to the cornea reduces stromal edema and inflammation, promoting faster wound closure and a more uniform repair of the epithelial basal lamina after laser ablation.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 12-2014
DOI: 10.1016/J.JCRS.2014.03.025
Abstract: To assess the effectiveness of toric intraocular lenses (IOLs) in the management of post-keratoplasty astigmatism. Public university hospital, Auckland, New Zealand. Retrospective case series. The study analyzed post-keratoplasty eyes after cataract surgery and toric IOL (Acrysof SN60AT or T-flex 623T/573T) implantation. Twenty-six eyes were included. The mean age at cataract surgery was 57.1 years ± 11.2 (SD). Previous keratoplasty was penetrating (84.6%) or deep anterior lamellar (15.4%). Keratoconus (73.1%) was the major indication for keratoplasty. The mean IOL cylinder power was 6.85 ± 3.02 diopters (D). No IOL required postoperative realignment. The mean follow-up was 14 ± 11 months. The mean refractive spherical equivalent decreased significantly, from -3.67 ± 5.76 D to -0.58 ± 1.71 D (P=.01). The mean refractive astigmatism also decreased significantly, from -5.49 ± 3.72 D to -2.61 ± 2.10 D (P<.01). There was a significant improvement in the mean uncorrected distance visual acuity (UDVA) (from 1.12 ± 0.67 logMAR to 0.45 ± 0.39 logMAR) and in the mean corrected distance visual acuity (CDVA) (from 0.70 ± 0.66 logMAR to 0.15 ± 0.16 logMAR) from preoperatively to the last follow-up (both P<.01). Postoperatively, the UDVA and CDVA were 20/40 or better in 61.5% of eyes and 92.3% of eyes, respectively. Cataract surgery with toric IOL implantation was safe and effective in significantly reducing corneal astigmatism and improving visual acuity in a large cohort of post-keratoplasty eyes.
Publisher: Elsevier BV
Date: 09-2013
DOI: 10.1016/J.SURVOPHTHAL.2012.12.003
Abstract: In vivo confocal microscopy (IVCM) is a non-invasive method of examining the living human cornea. The recent trend towards quantitative studies using IVCM has led to the development of a variety of methods for quantifying image parameters. When selecting IVCM images for quantitative analysis, it is important to be consistent regarding the location, depth, and quality of images. All images should be de-identified, randomized, and calibrated prior to analysis. Numerous image analysis software are available, each with their own advantages and disadvantages. Criteria for analyzing corneal epithelium, sub-basal nerves, keratocytes, endothelium, and immune/inflammatory cells have been developed, although there is inconsistency among research groups regarding parameter definition. The quantification of stromal nerve parameters, however, remains a challenge. Most studies report lower inter-observer repeatability compared with intra-observer repeatability, and observer experience is known to be an important factor. Standardization of IVCM image analysis through the use of a reading center would be crucial for any future large, multi-centre clinical trials using IVCM.
Publisher: Informa UK Limited
Date: 03-2013
DOI: 10.1111/CXO.12043
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 08-2001
DOI: 10.1016/S0886-3350(01)00753-2
Abstract: We report a case of epithelial ingrowth through a buttonhole 6 months after laser in situ keratomileusis. Elevation topography showed irregular astigmatism and an unreliable pachymetric map. In vivo confocal microscopy showed an epithelial basal cell mosaic with prominent borders and distinct nuclei. No corneal nerves were identified in any image. Cells in the anterior stroma possessed bright, reflective nuclei and appeared to form clusters. The interface between the stromal bed and the flap had formation of nests of fibrotic tissue and epithelial cells.
Publisher: Elsevier BV
Date: 11-2016
DOI: 10.1016/J.AJO.2016.09.003
Abstract: To evaluate 2 preoperative risk stratification systems for assessing the risk of complications in phacoemulsification cataract surgery, performed by residents, fellows, and attending physicians in a public teaching hospital. Cohort study. One observer assessed the clinical data of 500 consecutive cases, prior to phacoemulsification cataract surgery performed between April and June 2015 at Greenlane Clinical Centre, Auckland, New Zealand. Preoperatively 2 risk scores were calculated for each case using the Muhtaseb and Buckinghamshire risk stratification systems. Complications, intraoperative and postoperative, and visual outcomes were analyzed in relation to these risk scores. Intraoperative complication rates increased with higher risk scores using the Muhtaseb or Buckinghamshire stratification system (P = .001 and P = .003, respectively, n = 500). The odds ratios for residents and fellows were not significantly different from attending physicians after case-mix adjustment according to risk scores (P > .05). Postoperative complication rates increased with higher Buckinghamshire risk scores but not with Muhtaseb scores (P = .014 and P = .094, respectively, n = 476). Postoperative corrected-distance visual acuity was poorer with higher risk scores (P < .001 for both, n = 476). This study confirms that the risk of intraoperative complications increases with higher preoperative risk scores. Furthermore, higher risk scores correlate with poorer postoperative visual acuity and the Buckinghamshire risk score also correlates with postoperative complications. Therefore, preoperative assessment using such risk stratification systems could assist in idual informed consent, preoperative surgical planning, safe allocation of cases to trainees, and more meaningful analyses of outcomes for in idual surgeons and institutions.
Publisher: Elsevier BV
Date: 09-2011
DOI: 10.1016/J.OPHTHA.2011.02.025
Abstract: To characterize the influence of tilt angle, decentration, and pupil size on the higher-order aberration (HOA) profile of 3 aspheric intraocular lenses (IOLs) using a physical model eye. A 4-factor (model, pupil, angle, decentration) in vitro experimental design comparing 3 aspheric IOLs using a physical model eye. Measurements of HOA were obtained using the Zywave aberrometer (Bausch & Lomb, Rochester, NY) and a purpose-built physical model eye. The following IOLs were assessed with various levels and combinations of pupil diameter, decentration, and tilt angle: the AcrySof IQ SN60WF aspheric (Alcon, Hünenberg, Switzerland), Technis ZA9003 aspheric (Advanced Medical Optics, Santa Ana, CA), and Adapt Advanced Optics (Bausch & Lomb). Fifteen Zernike modes were compared using multivariate analysis of variance, canonical discrimination, and regression analysis. Four identical IOLs of each IOL model were assessed at all possible combinations of 3 pupil sizes, 4 levels of decentration, and 4 tilt angles. In idual HOA from z200 to z550. Pupil size, decentration, model, and tilt angle all had statically significant effects on the HOA profile. Pupil size contributed most to observed total variability (54.9%), followed by decentration (22.7%), then model (16.6%), and finally tilt angle (5.7%). All factors demonstrated significant interaction terms with respect to HOA. Intraocular lenses with increased aspheric properties inherent in the design of the optic were more sensitive to decentration and change in pupil size. The 3 IOL models demonstrated significant differences in HOAs in response to changes in pupil size, decentration, and tilt angle. All IOL models assessed in this study demonstrated minimal HOA at small pupil diameters. The IOL models with lower, or an absence of, negative spherical aberration were most robust to displacement with increased decentration and tilt angle.
Publisher: Informa UK Limited
Date: 03-2013
DOI: 10.1111/CXO.12048
Abstract: The aim was to identify potential factors associated with acute corneal hydrops in a New Zealand population with keratoconus referred to a hospital eye service. In a single hospital centre, in a retrospective review, demographic and clinical features of subjects with keratoconus and corneal hydrops over a 17-year period were compared with an age- and gender-matched control group of subjects with keratoconus but no history of corneal hydrops. One hundred and one eyes of 101 subjects (mean age 24.6 ± 8.4 years) were identified with keratoconus-related corneal hydrops. Subjects were more likely to be of Pacific but less likely to be of New Zealand European ethnicity than control subjects (n = 101). In comparison, Maori ethnicity was not found to have a significantly positive or negative association with hydrops. The pre-hydrops visual acuity (VA) of affected eyes was poorer than that of controls (p < 0.001) at first presentation to our tertiary referral corneal and contact lens service. Hydrops typically developed approximately four years after diagnosis of keratoconus. Subjects with hydrops were more likely to have a history of eye-rubbing (p = 0.011) but less likely to have a family history of keratoconus (p = 0.05). In 31 cases, the acute hydrops event was their first optometric/ophthalmologic contact. There were no statistically significant differences in the prevalence of atopic disease, contact lens wear or overall corneal transplantation rate between the two groups. Pacific ethnicity, history of eye-rubbing, poor VA at first hospital presentation and lack of family history were statistically associated with developing acute corneal hydrops in keratoconus in a New Zealand population. Greater understanding of such predisposing risk factors may help develop early management strategies to delay or prevent progression of this disease.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 07-2008
DOI: 10.1016/J.JCRS.2008.03.024
Abstract: To examine the evidence that a series of cases of diffuse lamellar keratitis (DLK) after laser in situ keratomileusis (LASIK) was caused by a type of marker pen. Eye Institute, Auckland, New Zealand. During a 10-week period, 522 consecutive LASIK procedures were performed using a 60 Hz IntraLase femtosecond laser (IntraLase Corp.) to create the LASIK flap and a 217Z 100 Hz excimer laser (Bausch & Lomb) to perform the refractive ablation. As standard practice, a marking pen was used to enable accurate flap realignment. Three weeks after a sudden increase in the incidence of DLK was identified, one of the 5 surgeons performed 5 consecutive bilateral cases using the marking pen in the right eyes but not in the left eyes. Of the 522 LASIK cases (119 without marking pen, 403 with marking pen), DLK developed in 49 (9.4%). No eye treated without the marking pen developed DLK of those in which the marking pen was used, 49 (12.2%) developed DLK (P<0.0001, Fischer exact test odds ratio, 27). In the 5 consecutive bilateral cases in which the marking pen was used in the right eye but not the left eye, 4 right eyes and no left eye developed DLK (P=0.03). Forty-five of the 49 eyes with DLK quickly recovered. The other 4 developed central toxic keratopathy. There is strong statistical evidence that the marking pen was a factor in the occurrence of DLK.
Publisher: Wiley
Date: 10-2004
Publisher: Association for Research in Vision and Ophthalmology (ARVO)
Date: 29-10-2015
Abstract: To examine and evaluate ocular biomechanical metrics and additionally derived corneal and orbital components using a noncontact Scheimpflug-based tonometer (CorVis ST) in a population of healthy eyes. A total of 152 eyes of 152 participants were examined by slit-l biomicroscopy, corneal tomography, and the CorVis ST (CST). This determined the distribution of outputs from the CST, such as deformation litude (DA), and additionally derived parameters, including maximum corneal deformation (MCD), maximum orbital deformation (MOD), and corneal energy dissipation (CED). The mean age of participants was 35.88 ± 13.8 years. Deformation litude significantly correlated with age (r = 0.24, P = 0.002) but not sex or ethnicity (P > 0.05). Multiple linear regression analysis revealed significant correlations between DA and age (r = 0.19, P = 0.006) and DA and IOP (r = -0.59, P < 0.001). Age correlated with MCD (r = 0.20, P = 0.01), MOD (r = 0.18, P = 0.03), and CED (r = 0.39, P 0.05). There were no significant differences between ethnicities for MCD, MOD, and CED (P > 0.05). Multiple linear regression analysis revealed significant correlations between MCD and IOP (r = -0.65, P < 0.001), CED and age (r = 0.41, P < 0.001), CED and IOP (r = 0.28, P = 0.001), and between CED and central corneal thickness (CCT) (r = -0.36, P < 0.001). The isolation of the corneal component (MCD) should be used when analyzing deformation characteristics in diseases that only affect the cornea. This study establishes a baseline for a population of healthy eyes. Future publications will identify differences in MCD, MOD, and CED between healthy and diseased populations.
Publisher: Elsevier BV
Date: 1993
DOI: 10.1016/0731-7085(93)80091-E
Abstract: Isolated bovine cornea was found to reduce the 20 ketone group in fluorometholone (FML) to produce a mixture of 20 alpha- and 20 beta-dihydrofluorometholone (DHFML). Incubation of FML with bovine cornea at pH 7.4 in phosphate buffer produced an increase in the amount of reduction products up to 8 h after this time the rate of reduction decreased. The reduced products were quantified by GC-MS against [2H3] 20 alpha-DHFML. Variable amounts of 20 beta-DHFML were detected in six s les of human aqueous humour following topical application of 50 micrograms of FML to the eye. The rapid metabolism of the side chain of FML may account for the unexpected low concentrations of FML which are found in human aqueous humour following its application to the surface of the eye.
Publisher: Research Square Platform LLC
Date: 20-09-2023
Publisher: BMJ
Date: 19-11-2009
Abstract: The exponential evolution of in vivo confocal microscopy (IVCM) has led to a significant enhancement in our knowledge of the living cornea in both its physiological and pathological states. Studies using white light and coherent light-based IVCM have enabled detailed quantitative analysis of sub-basal nerve parameters, and have also resulted in the elucidation of the two-dimensional architecture of the normal corneal sub-basal nerve plexus. However, accurate and repeatable methods for quantitative analysis of stromal nerves imaged by IVCM remain to be developed. The effect of corneal surgery on central corneal nerves has been well documented in many IVCM studies, and these studies provide an indication of the regenerative capacity of corneal nerves. IVCM has also clearly demonstrated the involvement of corneal nerves in diseases such as keratoconus, although it remains unclear whether these alterations are a cause of, or occur secondary to, the disease process. IVCM has also been proposed as non-invasive method of accurately diagnosing and assessing the progression of diabetic neuropathy, highlighting the potential application of this technique as an indicator of systemic disease. This review consolidates our knowledge of how IVCM has contributed significantly to our greater understanding of corneal nerves in the living human cornea in health and disease.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 10-2008
DOI: 10.1016/J.JCRS.2008.04.053
Abstract: The unilateral epikeratophakic eye of a 20-year-old woman with a history of congenital cataracts was examined using laser scanning in vivo confocal microscopy 17 years after transplantation. In vivo confocal microscopy demonstrated a reduced keratocyte density in the grafted lenticule and the host stroma, with unusual elongated and tortuous hyperreflective branching structures in the anterior stroma of the host cornea. The sub-basal nerve plexus was present in the lenticule, although with a reduced nerve density. The appearance of the host endothelium was similar to that observed in Fuchs endothelial dystrophy. Dramatic microstructural changes were observed in almost all layers of the cornea 17 years after epikeratophakia. Although no longer performed as routine practice, in vivo confocal microscopy examination of epikeratophakia has provided fascinating insight into the potential corneal adaptations at a cellular level.
Publisher: Public Library of Science (PLoS)
Date: 28-10-2016
Publisher: Elsevier BV
Date: 08-2021
Publisher: Wiley
Date: 23-01-2020
DOI: 10.1111/CEO.13709
Abstract: Inflammatory ocular diseases are associated with systemic disease, ocular morbidity and mortality. To examine clinical characteristics of subjects with peripheral ulcerative keratitis (PUK) and necrotising scleritis. Retrospective case series in a single tertiary centre over 10 years. All patients presenting with necrotising scleritis, PUK or scleritis with corneal infiltrates. Fifty-two eyes (41 subjects) were identified. Demographic and clinical data analysis. Visual loss, ocular complications and mortality. Mean follow up was 7.0 ± 5.3 years, presentation age 51.3 ± 18.6 years, and 23 subjects (56.1%) were female. Overall, 27 eyes presented with PUK, 26 with necrotising scleritis, and 22 with corneal infiltrates associated with active scleritis. Associated systemic diagnosis was observed in 12 subjects at presentation, and in 21 subjects (51.2%) by final follow up. Recurrence occurred in 23 eyes (44.2%): 10 eyes experiencing PUK or necrotising scleritis 13 eyes with non-necrotising scleritis. Perforation occurred in six eyes (11.5%). Moderate vision loss occurred in 10 eyes (19.2%) and severe loss in six eyes (11.5%). Five subjects (12.2%) were deceased by study conclusion, of whom four were not on immunomodulatory therapy (IMT). A marked difference in estimated survival was observed with IMT, with mean estimated survival of 10.7 years without treatment, compared to 24.7 years with IMT (P = .045). PUK and necrotising scleritis represent a severe inflammatory disease with high rates of perforation, visual loss and mortality. IMT was associated with a lower rate of mortality and longer estimated survival in this group.
Publisher: Wiley
Date: 03-2009
DOI: 10.1111/J.1442-9071.2009.02009.X
Abstract: The first detailed descriptions of keratoconus were published exactly 150 years ago in the original work of Dr John Nottingham, bringing a degree of clarity to a previously confusing clinical phenomenon--further supported by observations of other contemporaries in the field such as Sir William Bowman. However, it would be another 100 years before knowledge of keratoconus would grow substantially indeed, our current level of understanding is primarily a result of extensive clinical and laboratory research conducted over the last 50 years--particularly based upon the enormous technological advances of the last two decades. Large clinical studies have confirmed that keratoconus is a non-inflammatory corneal disease with central or paracentral corneal thinning, which exhibits progressive corneal steepening and protrusion that typically results in increasing regular and thereafter irregular astigmatism. Ultimately, disease progression may lead to corneal scarring, corneal hydrops and loss of best spectacle-corrected visual acuity. Although visual rehabilitation may be effected by expert contact lens fitting, 20% of subjects may require corneal transplantation. This Gregg lecture provides a highly referenced, wide-ranging overview of both historical and contemporary aspects of keratoconus, including diagnostic, phenotypic and prognostic factors revealed by large clinical studies, critical diagnostic advances enabled by Placido and slit-scanning computerized corneal topography, the emerging roles of higher order aberration wave-front analysis and corneal hysteresis in delineating early and subclinical keratoconus, inheritance and genetic predisposition to keratoconus, corneal microstructural changes unveiled by in vivo confocal microscopy, unifying theories to explain associations between keratoconus, atopy, eye rubbing and keratocyte apoptosis, and surgical options for keratoconus, such as corneal transplantation, intrastromal ring segments, collagen cross-linking and keratocyte transplantation. However, 150 years along the path our knowledge of keratoconus remains incomplete, but technological advances should enable us to put together the final pieces of the jigsaw in the foreseeable future.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 2015
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 02-2017
DOI: 10.1016/J.JCRS.2016.12.014
Abstract: We describe 7 cases in which supplementary sulcus-based toric intraocular lenses (IOLs) rotated postoperatively, requiring surgical realignment. The initial rotation was identified clinically between 3 months and 36 months postoperatively. All eyes had keratoconus, with and without prior keratoplasty, and 6 had longer than average axial lengths. No preceding trauma could be identified for 5 of the eyes. One eye had 3 episodes of postoperative IOL rotation, eventually requiring suture fixation to stabilize the IOL. This series indicates that postoperative rotation of a supplementary sulcus-based toric IOL may occur in eyes with or without preceding trauma. Eyes with keratoconus are at risk for postoperative rotation of the IOL, and suture fixation may be required to obtain stability.
Publisher: Wiley
Date: 06-08-2020
DOI: 10.1111/CEO.13825
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 03-2003
DOI: 10.1016/S0886-3350(03)00049-X
Abstract: We report 3 members of an extended family who presented with bilateral peripheral corneal edema consistent with Brown-McLean syndrome. On clinical examination, all eyes demonstrated normal central corneas and marked peripheral edema. In vivo confocal microscopy of the peripheral cornea highlighted similar observations in the 6 eyes including endothelial pigmentation, masked stromal structure due to edema, prominent nerves, and localized basal epithelial edema. In the central cornea, in vivo confocal microscopic observations highlighted large cellular structures with prominent nuclei in groups consisting of several cells of similar appearance. In vivo confocal microscopy may enhance the diagnosis of Brown-McLean syndrome and may be used for dynamic evaluation and postoperative follow-up of the structural corneal changes.
Publisher: Informa UK Limited
Date: 11-2017
DOI: 10.1111/CXO.12510
Publisher: Springer Science and Business Media LLC
Date: 03-08-2012
DOI: 10.1038/EYE.2012.155
Publisher: Elsevier BV
Date: 12-1991
DOI: 10.1016/0378-4347(91)80437-H
Abstract: (-)-Bunolol (LB) was applied to the human eye in a commercially available eye drop formulation. LB and its metabolite, dihydro-(-)-bunolol (DHLB) were identified and quantified in human aqueous humour. The compounds were analysed as their trimethylsilyl-pentafluorobenzamide derivatives using gas chromatography-negative ion chemical ionisation mass spectrometry. In the case of DHLB the corresponding 2H3-labelled isotopomers were used as internal standards and LB was quantified against its methoxime derivative. Calibration curves for LB and DHLB against internal standards were linear with correlation coefficients 0.994 and 0.996, respectively. Replicate analyses of a pooled s le of aqueous humour containing LB and DHLB gave standard errors of the mean of +/- 9.8 and +/- 2.4% for the concentrations of LB and DHLB, respectively. The practical limit of detection of the method was ca. 30 pg for LB and ca. 100 pg for DHLB. The derivatization procedure was also satisfactory for the analysis of a number of other beta-blockers which are used in ophthalmological practice.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 2010
Publisher: Wiley
Date: 2010
DOI: 10.1111/J.1442-9071.2009.02182.X
Abstract: To investigate the presentation, clinical characteristics and outcomes of Acanthamoeba keratitis (AK) in Auckland, New Zealand over a 7-year period. Retrospective analysis of all cases of AK treated by the tertiary corneal service at Auckland City Hospital/ University of Auckland Department of Ophthalmology (August 2001 to May 2008). Data were collected regarding age, gender, contact lens history, presenting signs and symptoms, diagnosis at first presentation, time to final diagnosis, identifiable risk factors, presenting and final visual acuity, results of microbiological testing, medical treatment, surgical interventions, recurrence of disease and length of follow up. All photographs and in vivo confocal microscopy images were reviewed. Twenty-five eyes of 25 patients were identified with a diagnosis of AK (mean age 40 +/- 13 years). Ninety-six per cent were contact lens wearers. Mean time to diagnosis was 41 +/- 49 days (range 0-181 days, median 21 days). Fourteen patients (56%) had been treated with topical corticosteroids prior to the diagnosis. Early diagnosis of AK (<21 days) was associated with significantly better final visual acuity and did not require any surgical intervention compared with those diagnosed at a later stage. Six patients, all in the late diagnosis group, required surgical intervention. AK has become significantly more common in New Zealand in the current decade. This study highlights the fundamental importance of early diagnosis and appropriate management in ensuring favourable outcomes. Practitioners should maintain a clinical suspicion of AK, especially as 96% of the subjects in this study were contact lens wearers.
Publisher: Association for Research in Vision and Ophthalmology (ARVO)
Date: 04-08-2015
Abstract: We investigated the relationship between corneal subbasal nerve (SBN) plexus density, corneal sensitivity, and peripheral and cardiac autonomic neuropathy in patients with type 1 diabetes mellitus. We recruited 53 patients with type 1 diabetes mellitus and 40 normal control participants. Corneal in vivo confocal microscopy (IVCM) and sensitivity testing were performed on one eye of each subject. Autonomic function testing was done and an overall neuropathy score obtained from a combination of a symptomatic neuropathy score, clinical assessment, biothesiometry, and nerve conduction tests. The corneal SBN density (P < 0.001) and corneal sensitivity (P < 0.001) were significantly lower in subjects with diabetes compared to controls. A modest negative correlation between total neuropathy score and SBN density was observed (r = -0.33, P = 0.01). A negative correlation between corneal sensitivity and expiration/inspiration component of the autonomic nerve analysis (ANS-EI) also was noted (r = -0.36, P = 0.008). Corneal SBN density was abnormal in 50% of diabetic subjects classified as "Normal" by the clinical and electrophysiological based tests of total neuropathy score. The correlation of corneal SBN density with total neuropathy score suggests that reduced corneal nerve density reflects peripheral neuropathy in diabetes. Corneal SBN changes precede other clinical and electrophysiology tests of neuropathy supporting a possible role for corneal IVCM and corneal sensitivity testing as surrogate markers in the assessment of diabetic peripheral and cardiac autonomic neuropathy.
Publisher: Public Library of Science (PLoS)
Date: 18-06-2021
DOI: 10.1371/JOURNAL.PONE.0248350
Abstract: To investigate the repeatability in corneal thickness (CT) and epithelial thickness (ET) measurements using spectral domain anterior segment optical coherence tomography (AS-OCT, REVO NX, Optopol) in keratoconus, and examine the effect of corneal crosslinking (CXL) on repeatability. A cross-sectional study of 259 eyes of 212 patients with keratoconus attending the corneal disease clinic at a university hospital tertiary referral center were enrolled. Two groups were analysed: eyes with no prior history of CXL (Group A) and eyes with prior CXL (Group B). Repeatability of measurements was assessed using the intraclass correlation coefficient (ICC) and coefficient of variation (CV). In Group A, central corneal thickness (CCT) was 472.18 ± 45.41μm, and the ET was found to be the thinnest in the inferior-temporal aspect at 51.79 ± 5.97μm and thickest at the superior-nasal aspect at 56.07 ± 5.70μm. In Group B, CCT was 465.11± 42.28μm, and the ET was the thinnest at the inferior-temporal aspect at 50.63 ± 5.52μm and thickest at the superior aspect at 56.80 ± 6.39μm. When evaluating CT measurements, ICC was above 0.86 and 0.83 for Group A and Group B respectively. When evaluating ET measurements, ICC was above 0.82 for both groups. CXL had no statistically significant impact on the repeatability of measurements. AS-OCT provides repeatable CT and ET measurements in the central and peripheral cornea in patients with keratoconus. Repeatability is not affected by a history of CXL.
Publisher: Wiley
Date: 04-2011
DOI: 10.1111/J.1442-9071.2010.02435.X
Abstract: The cornea is densely innervated, and the integrity of these nerve fibres is critical in maintaining the refractive and protective functions of the cornea. Many ocular and systemic diseases can adversely affect corneal sensory nerves and consequently impair their function, with vision loss being the inevitable consequence of severe corneal neurotrophic ulceration. However, current standard treatments regimens are often ineffective. Over the past three decades, the role of growth factors in maintaining the normal structure and function of the cornea, and in corneal epithelial healing, has become increasingly evident. Many preclinical and clinical trials have shown that growth factors and cytokines can significantly enhance epithelialization (epithelial proliferation and migration) and consequently accelerate wound healing. More recently, local/topical administration of insulin, naltrexone (opioid antagonist) and nicergoline (ergoline derivatives) were found to improve, and significantly increase, the corneal wound healing rate. This report reviews the major attributes of these growth factors and therapeutic agents that may be used in ameliorating impaired corneal wound healing, and presents a perspective on the potential clinical use of these agents as a new generation of ophthalmic pharmaceuticals for the treatment of diabetic keratopathy.
Publisher: BMJ
Date: 12-04-2014
DOI: 10.1136/BJOPHTHALMOL-2013-304660
Abstract: Severe bacterial keratitis (BK) typically requires intensive antimicrobial therapy. Empiric therapy is usually with a topical fluoroquinolone or fortified aminoglycoside-cephalosporin combination. Trials to date have not reached any consensus as to which antibiotic regimen most effectively treats BK. A systematic review and meta-analysis using Cochrane methodology was undertaken to evaluate the effectiveness of topical antibiotics in the management of BK. Outcomes included treatment success, time to cure, serious complications of infection and adverse effects. A comprehensive search for trials resulted in 27 956 abstracts for review. This eventually resulted in 16 high quality trials involving 1823 participants included in the review. Treatment success, time to cure and serious complications of infection were comparable among all antibiotic treatments included in the review. Furthermore, there was no evidence of difference in the risk of corneal perforation with any included antibiotics or antibiotic classes. Fluoroquinolones significantly reduced risk of ocular discomfort and chemical conjunctivitis but increased the risk of white precipitate formation compared with aminoglycoside-cephalosporin. Fortified tobramycin-cefazolin was approximately three times more likely to cause ocular discomfort than other topical antibiotics. Results of this review suggest no evidence of difference in comparative effectiveness between fluoroquinolones and aminoglycoside-cephalosporin treatment options in the management of BK. There were differences in safety profile, however. Fluoroquinolones decreased the risk of ocular discomfort and chemical conjunctivitis while ciprofloxacin increased the risk of white corneal precipitate compared with aminoglycoside-cephalosporin.
Publisher: Wiley
Date: 19-10-2007
DOI: 10.1111/J.1475-1313.2007.00524.X
Abstract: To investigate and correlate optical correction, and progression to penetrating keratoplasty (PKP), with the corneal, refractive, topographic and familial characteristics of subjects with keratoconus, within the Tayside region of Scotland. Prospective, observational, longitudinal study design. Two hundred subjects with keratoconus were enrolled into the Dundee University Scottish Keratoconus Study (DUSKS) and were assessed during a 4-year period using standardised clinical assessment, computerised corneal topography and questionnaires. Keratoconic subjects in this study wore rigid contact lenses (90.6%) for longer than 12 hours per day (81%), 7 days a week (91%) and achieved a very good level of Snellen visual acuity (97%, > or =6/9). Corneal staining was observed in the majority of corneas (71%), although only a small percentage of subjects reported major problems of: discomfort (18%), hyperaemia (16%), or the lens falling out (4%). Poor visual acuity was the main reason (79%) for undergoing PKP usually in the latter part of the third decade of life, approximately a decade after diagnosis. During the study period 4% of eyes progressed to PKP. Only a small percentage of eyes (9.5%) required no visual correction postoperatively. The main mode of visual rehabilitation for keratoconus was rigid contact lenses, which were mostly worn successfully with good visual acuity. During the study period a small minority of keratoconics progressed to corneal graft surgery. It is advisable to emphasise that postoperatively refractive correction will be required in the majority of these cases.
Publisher: Springer Science and Business Media LLC
Date: 03-2003
DOI: 10.1007/S10103-002-0245-3
Abstract: We have examined 30 laser pointers that have been removed from the possession of accused persons by police in Scotland. An analysis has shown that 28 were Class 3B (European), with radiated power up to 9.3 mW. We have reviewed the relevance of these findings and this shows that they are potentially hazardous if viewed directly. Transient exposure is unlikely to cause long-term damage but prolonged exposure may cause permanent retinal injury. They may also cause dazzle, the consequences of which could be serious.
Publisher: Informa UK Limited
Date: 09-2019
DOI: 10.1111/CXO.12866
Publisher: Informa UK Limited
Date: 22-01-2020
Publisher: Wiley
Date: 27-06-2021
DOI: 10.1111/CEO.13958
Abstract: Megalocornea and anterior megalophthalmos (megalocornea spectrum) disorders are typically defined by corneal diameter 12.5 mm in the absence of elevated intraocular pressure. Clinical features overlap with keratoglobus but are distinct from buphthalmos and severe (globus) keratoconus. Megalocornea spectrum disorders and keratoglobus are primarily congenital disorders, often with syndromic associations both can present with large and thin corneas, creating difficulty in diagnosis, however, only keratoglobus is typically progressive. Molecular genetics provide significant insight into underlying aetiologies. Nonetheless, careful clinical assessment remains intrinsic to diagnosis. Surgical management can be challenging due to the enlarged ciliary ring and weakened zonules in megalocornea spectrum disorders and the extreme corneal thinning of keratoglobus. In this review, the established literature on measurement of corneal diameter, diagnosis of megalocornea, anterior megalophthalmos and keratoglobus, differentiation from severe keratoconus, recent molecular genetics research and key surgical modalities in the management of these rare disorders are outlined and discussed.
Publisher: Wiley
Date: 30-06-2021
DOI: 10.1111/CEO.13959
Abstract: Few studies have evaluated corneal crosslinking (CXL) in a prospective, randomised fashion. This study aimed to determine the efficacy and safety of CXL to reduce the progression of keratoconus. Prospective, unmasked, randomised, contralateral eye controlled trial at a tertiary eye centre. Participants : In iduals with bilateral progressive keratoconus. One eye from each subject was randomised to CXL and the contralateral, untreated eye acted as the control. Primary outcome measure : change in maximum keratometry. Secondary outcome measures : uncorrected distance visual acuity, spectacle corrected distance visual acuity, spherical equivalent refraction, simulated keratometry, corneal astigmatism, minimum pachymetry and complications. Thirty‐eight in iduals (mean age 21.1 ± 6.7 years) were enrolled with one eye treated with CXL. At 5 years, there was a mean decrease in maximum keratometry of treated eyes (−1.45 ± 2.25 D) compared to an increase among the controls (1.71 ± 2.46 D p 0.001). There were significant differences between the treated and control groups in the mean change of Steep SimK (−1.07 ± 1.22 vs. 0.96 ± 1.97 D p 0.001), Flat SimK (−0.61 ± 1.34 vs. 0.43 ± 1.12 D p 0.001), corneal astigmatism (−0.45 ± 1.31 vs. 0.63 ± 1.52 D p 0.01) and minimum pachymetry (−32.49 ± 26.32 vs. −13.57 ± 24.11 μm p 0.01). Complications included sterile infiltrates ( n = 2), microbial keratitis ( n = 1), persistent corneal haze/scarring at 5 years ( n = 4) and loss of ≥2 lines of corrected distance visual acuity ( n = 3). CXL is an effective and relatively safe intervention to halt or reduce the progression of keratoconus in the majority of eyes for at least 5 years.
Publisher: Wiley
Date: 12-2007
Publisher: BMJ
Date: 11-10-2017
DOI: 10.1136/BJOPHTHALMOL-2016-308682
Abstract: To determine if significant progression of disease occurs in older, non-contact lens wearing, subjects with keratoconus and to identify potential predictive factors. Clinical and computerised corneal topography records of subjects with keratoconus attending a specialist optometry practice were retrospectively analysed to identify those aged ≥30 years, with ≥2 consultations ≥12 months apart, no contact lens wear and no corneal scarring, surgery or corneal hydrops. Topographic parameters assessed included: maximum keratometry (Kmax), steep keratometry (Ksteep), flat keratometry (Kflat), inferior-superior (I-S) ratio and the surface asymmetry and regularity (surface asymmetry index and surface regularity index) indices. Of the 449 subjects with keratoconus assessed, 43 eyes of 27 patients (6.01%) met inclusion criteria, with median age 38.45 (12.86) years at baseline and median follow-up 4.36 (8.68) years. There was a significant increase in Kmax (0.30 (1.21) D), Ksteep (0.27 (0.90) D), Kflat (0.34 (1.12) D) and I-S (0.26 (0.82) D) between baseline and final review, p<0.05. Notably, 18.6%-25.6% of eyes demonstrated ≥1.00 D increase in one or more of four principal topographic parameters (Kmax, Ksteep, Kflat, I-S ratio), while 18.5%-37.0% of subjects had ≥1.00 D increase in the aforementioned parameters in at least one eye over the study period. However, <10% of eyes exhibited ≥1.00 D increase/year in all topographic parameters. The only significant predictor of progression was follow-up time. This study confirms that keratoconus may continue to progress beyond age 30. Older subjects with keratoconus should be monitored for progression, particularly with respect to possible corneal collagen cross-linking or astigmatic correction in cataract surgery.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 07-2005
DOI: 10.1097/01.ICO.0000155035.55751.B2
Abstract: To evaluate donor demographics and source, donor tissue processing and storage, biologic contamination, and the utilization and distribution of corneal tissue procured by the New Zealand National Eye Bank. As part of a prospective longitudinal study, the electronic records of the NZNEB for the 13-year period 1991-2003 were analyzed for each year with respect to donor demographics, donor source and cause of death, death-to-preservation interval, storage methods, endothelial assessment, biologic contamination, corneal tissue utilization, and distribution. During the study period, 3221 corneas were retrieved from 1628 donors (69.8% male, 30.2% female), with the mean age of donors 59.4 years (SD 18.3 years) and range 4 to 95 years. No significant correlation was identified between donor age group (using 10-year intervals) and the proportion of corneas suitable for transplantation. Donors were procured from the Coroner's service (67.6%), public hospitals, (23.5%) and multiorgan donors (7.1%). The most common causes of donor death were cardiovascular disease, trauma, and cerebrovascular disease. Average storage duration increased from 3.5 to 11.8 days when organ culture replaced hypothermic storage in 1992. Biologic contamination occurred in 5% of all donor corneas. The most common bacterial and fungal isolates were coagulase-negative staphylococci and Candida spp, respectively. A significant decrease in contamination rate over the years of the study was identified. Overall, 79.4% of corneal tissue procured was used for corneal transplantation (75.8% for penetrating keratoplasty, 2.1% for lamellar keratoplasty, and 1.5% for unspecified transplants), and 21.6% was discarded. Most common reasons for discarding tissue were biologic contamination, abnormal serology, and failed endothelial assessment. Analysis of the NZNEB database provides valuable information in relation to eye banking and corneal transplantation in New Zealand. Significant trends were identified in donor demographics, donor procurement source, improved donor tissue processing and storage, decreased biologic contamination, and increased utilization of corneal tissue.
Publisher: Elsevier BV
Date: 2010
DOI: 10.1016/J.PRETEYERES.2009.11.001
Abstract: Confocal microscopy enables microstructural analysis of the in vivo cornea, allowing fresh insight into corneal microstructure in health, and in inherited and acquired corneal disease. This method of corneal examination is evolving in an exponential fashion, with rapid advances in technology being mirrored by rapid growth in both research and clinical applications. Whilst initially the evidence base for in vivo confocal microscopy consisted largely of small case studies, in recent years there has been a trend towards collecting quantitative data in an effort to better delineate between heath and disease. Confocal microscopy has been utilised clinically to aid in the diagnosis of infectious keratitis, in particular Acanthamoeba and fungal keratitis, and has also established a role in the diagnosis and phenotyping of corneal dystrophies. This article reviews in vivo confocal microscopy of the human cornea in health and disease and examines clinical and research applications of this new technology.
Publisher: Wiley
Date: 28-07-2004
Publisher: Wiley
Date: 06-2004
Publisher: BMJ
Date: 09-12-2017
DOI: 10.1136/BJOPHTHALMOL-2016-309532
Abstract: To compare the ocular biomechanical properties in patients with thyroid eye disease (TED) and healthy participants using a non-contact Scheimpflug-based tonometer (CorVis ST). All eyes were examined by slit l biomicroscopy, corneal tomography and the CorVis ST (CST). Patients with TED were examined by a fellowship trained oculoplastics specialist to determine status and assess severity. The outputs from CST and additionally derived parameters, including maximum orbital deformation (MOD), were compared between healthy participants and patients with TED using Student's t-test. Furthermore, a multiple linear regression analysis was used to control for various factors known to influence ocular biomechanical responses to an air pulse. This study included 20 patients with TED and compared them with a cohort of 152 healthy participants. The mean age of patients with TED was 46.7±19.0 years and the mean age of healthy participants was 35.9±13.8 years (p=0.03). There were no statistically significant differences in gender distributions between both groups (p>0.05). Several CST parameters were significantly different between groups (p<0.05). Of note, however, MOD was significantly lower in patients with TED (0.16±0.04 mm) compared with the healthy participants (0.25±0.05 mm, p<0.001). This dissimilarity remained even after controlling for the various cofactors. Receiver-operating characteristic analysis revealed an area under the curve of 0.91±0.04 (95% CI 0.84 to 0.98, p<0.001) for MOD. The in vivo ocular biomechanics as measured by the CST reflects a reduced orbital compliance. This method of ocular biomechanical assessment may aid in the categorisation of TED severity and assist in monitoring and/or diagnosing TED.
Publisher: Elsevier BV
Date: 2019
DOI: 10.1016/J.AJO.2018.09.026
Abstract: To assess intraoperative complications of phacoemulsification surgery in public teaching hospital settings using modified preoperative risk stratification systems. Prospective cohort study. Preoperative risk stratification of 500 consecutive cataract cases using the New Zealand Cataract Risk Stratification (NZCRS) scoring system. Recommended allocation of higher-risk phacoemulsification procedures to experienced surgeons in public teaching hospital setting. Intraoperative complications relative to adherence to stratification recommendations. NZCRS classified 192 cases (38%) as high-risk, recommended for fellows or consultants (attendings). Primary surgeons were residents (n = 142, 28%), fellows (n = 88, 18%), and consultants (n = 270, 54%). Overall rate (N = 500) of any intraoperative complication was 5.0%. Where NZCRS scoring recommendations were observed (n = 448) the intraoperative complication rate was 4.5% but in "nonadherence" cases (n = 52 residents operating on higher-risk cases) this nearly doubled (9.6%). Postoperative complications occurred in 5.2%, primarily cystoid macular edema (3.7%). Postoperatively, mean unaided visual acuity was 6/12 (20/40) and best-corrected visual acuity improved from 6/20 (20/63) preoperatively to 6/10 (20/32) postoperatively (P < .05). The NZCRS system aids identification of higher-risk cataract cases and appropriate case-to-surgeon allocation and may increase surgeon awareness of risk factors. Compared to 2 previous studies under similar conditions in the same institution, the NZCRS system was associated with a 40% reduction in intraoperative complications (8.4% to 5%). The rate of posterior capsular tear was 0.6% (P = .035) compared to 2.6% in baseline phase and 1.4% in a prior risk stratification phase. Risk stratification seems to reduce intraoperative phacoemulsification complications in public teaching hospital settings.
Publisher: Informa UK Limited
Date: 11-2020
DOI: 10.1111/CXO.13036
Abstract: The measurement of corneal sensitivity threshold is important for several ocular surface diseases. The current study assesses the precision, agreement and utility of corneal sensitivity threshold measurement using a new, purpose-built non-contact corneal aesthesiometer. A new instrument and an established non-contact corneal aesthesiometer device was used to measure the corneal sensitivity threshold on the right eye of 40 healthy human participants. Exclusion criteria included: corneal pathology, previous ocular surgery, ocular trauma, contact lens wear, diabetes or peripheral neuropathy. A forced-response, double-staircase method was used to obtain corneal sensitivity threshold from the mean of three readings per participant, for each non-contact corneal aesthesiometer. Screen demarcations relative to the corneal limbus facilitated alignment with the new device. Repeatability of the new instrument was tested three consecutive times on the same day. Intra-observer and inter-observer reproducibility and agreement were determined using one-way analysis of variance or analysis of variance and Bland-Altman analysis, respectively. Forty eyes of 40 participants were assessed (15:25 M:F, 30.5 ± 11.4 years). The new instrument demonstrated good repeatability (p = 0.47). There was no difference in the mean corneal sensitivity threshold between the new (0.60 ± 0.36 mbar) and established (0.60 ± 0.34 mbar) aesthesiometers (p = 0.92). Utilising the new instrument, inter-observer reproducibility (on a different subset of 10 participants) yielded thresholds of 0.41 ± 0.16 mbar and 0.42 ± 0.13 mbar (p = 0.88) for the two observers. Bland-Altman analysis confirmed good intra and inter-observer agreement. Screen demarcations relative to the limbus, enabled easier corneal alignment. The new non-contact corneal aesthesiometer confirmed very good repeatability and reproducibility, as well as good agreement with the long-established instrument. Overall, this contemporary approach enables accurate and precise assessment of corneal sensitivity and thus, corneal nerve function, in normal and diseased cornea.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 08-2011
DOI: 10.1016/J.JCRS.2011.03.040
Abstract: To evaluate corneal tomographic features of keratoconus and associations between risk factors and disease phenotype in New Zealand. Departments of Ophthalmology, University of Auckland and Auckland District Health Board, Auckland, New Zealand. Clinic-based, cross-sectional study. The medical records and corneal tomography of patients attending a subspecialty service were reviewed. Data included age, sex, ethnicity, ocular history, family history, atopy, and eye rubbing. Orbscan II parameters included simulated keratometry, mean power, pachymetry, location of maximum power, anterior best-fit sphere (BFS) and posterior BFS. Morphology was categorized by the Rabinowitz topography classification. Final analyses included 532 eyes (266 patients 144 men) with a mean age of 29.3 years ± 11.56 (SD). Maori and Pacific patients were overrepresented (P=.0001). Family history of keratoconus was associated with a lower mean corneal power (P=.01) and greater pachymetry (P=.03). Comparing patients with family history and patients with atopy, showed differences in thinnest-point pachymetry (mean: family history, 340 ± 15 μm atopy 381 ± 8 μm) (P=.0218). Keratoconus was classified as severe (58.3%) or moderate (33.8%) on mean keratometry. Axial keratometric maps were predominantly asymmetric bow-tie (29%), round (18%), or inferior steepening (17%). Anterior elevation maps were classified as spur (49.3%), island (24%), irregular ridge (15%), or other (11.3%). Eighteen patients (12.5%) had complete enantiomorphism. Advanced keratoconus was largely asymmetric and differences in tomographic phenotype were associated with differing etiologic risk factors. Maori and Pacific ethnicities were overrepresented in this population.
Publisher: Wiley
Date: 05-03-2018
DOI: 10.1111/CEO.13166
Abstract: Acanthamoeba is an increasingly prevalent cause of vision-threatening microbial keratitis. To assess the incidence, clinical presentation, diagnosis and outcomes of patients with Acanthamoeba keratitis (AK) in Auckland, New Zealand over a 7-year period. Retrospective observational consecutive case series. Fifty-eight eyes of 52 patients diagnosed with AK. All cases of AK were identified using a cross-referenced search of clinical, laboratory and pharmacy records from March 2009 to May 2016. Demographic and clinical data were collected including age, gender, risk factors, clinical manifestations, initial diagnosis, diagnostic investigations, treatment, presenting and final visual acuity and surgical interventions. Contact lens (CL) use was noted in 96% of unilateral and 100% of bilateral cases. The mean duration of symptoms at presentation was 21 days and the mean duration from presentation to definitive diagnosis was 14 days. Initial diagnosis was recorded as CL-related keratitis in 70.6%, viral keratitis in 15.5% and AK in 12.0%. The diagnosis was confirmed with In vivo confocal microscopy (IVCM) in 67.2%, corneal scrape in 22.4%, corneal biopsy in 1.7% and clinically in 8.6%. IVCM sensitivity was 83.0%. Surgical intervention was required in four patients, all with delayed diagnosis (range 63-125 days). The incidence of AK has more than doubled when compared with the preceding 7-year period. AK is a rare vision-threatening protozoal infection with rapidly-increasing incidence in New Zealand, predominantly affecting CL users. Diagnosis is often challenging and when delayed is associated with worse outcomes. IVCM offers rapid diagnosis with high sensitivity.
Publisher: Association for Research in Vision and Ophthalmology (ARVO)
Date: 04-2006
DOI: 10.1167/IOVS.05-1217
Abstract: To produce a two-dimensional reconstruction map of the living corneal sub-basal nerve plexus in keratoconus with in vivo confocal microscopy. Four eyes of four subjects with keratoconus were examined by slit l biomicroscopy, Orbscan II slit-scanning elevation topography (Bausch & Lomb Surgical, Rochester, NY), and laser scanning in vivo confocal microscopy with the Heidelberg Retina Tomograph II, Rostock Corneal Module (Heidelberg Engineering, Heidelberg, Germany). Subjects were asked to fixate on targets arranged in a grid to enable in vivo confocal microscopy of the cornea in a wide range of positions. A mean of 402 +/- 57 images were obtained for each cornea, to create confluent montages. The mean dimensions of the corneal areas mapped were 6.60 +/- 0.70 mm horizontally and 5.91 +/- 0.72 mm vertically. All corneas exhibited abnormal sub-basal nerve architecture compared with patterns previously observed in normal corneas. At the apex of the cone, a tortuous network of nerve fiber bundles was noted, many of which formed closed loops. At the topographic base of the cone, nerve fiber bundles appeared to follow the contour of the base, with many of the bundles running concentrically in this region. Central sub-basal nerve density was significantly lower in keratoconus corneas (10,478 +/- 2,188 microm/mm2) compared with normal corneas (21,668 +/- 1,411 microm/mm2 Mann-Whitney P < 0.01). This is the first study to elucidate the overall distribution of sub-basal nerves in the living central to midperipheral human cornea in keratoconus, using laser scanning in vivo confocal microscopy.
Publisher: Wiley
Date: 03-2009
DOI: 10.1111/J.1442-9071.2008.01913.X
Abstract: There has been a significant increase in the number of reported cases of Acanthamoeba keratitis reported internationally over the last 24 months. Diagnosing Acanthamoeba keratitis is often difficult and part of the difficulty is attributed to the variability of presentation. This article provides a comprehensive photographic reference of common and uncommon clinical signs of Acanthamoeba keratitis.
Publisher: Wiley
Date: 28-09-2018
DOI: 10.1111/CEO.13041
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 2006
DOI: 10.1016/J.JCRS.2005.07.041
Abstract: As part of an ongoing series, this fourth article is the second of 2 related articles that deal with the basics of producing a high-quality manuscript. Although ophthalmology and vision science are the principal focus of this series, the general concepts essential to producing a quality manuscript are applicable to erse fields of research. This article provides guidelines on how to present research findings in a structured form using the Introduction, Methods, Results, and Discussion (IMRaD) style. The components to be included, and equally important excluded, from each section are elucidated in detail. Commonly omitted or inaccurately or incompletely presented components of the manuscript, such as statistical analysis and references, are highlighted. The necessity to carefully refine manuscripts before submission is discussed. This article concludes by illustrating methods of appropriately dealing with referees' comments and resubmitting manuscripts. Although researchers may have to deal with rejection as part of the process, we hope that this series provides an easy-to-follow structure to maximize manuscript quality and improve the prospect of scientific publication.
Publisher: Wiley
Date: 07-12-2016
DOI: 10.1111/CEO.12634
Abstract: The aim is to investigate ethnic variation, in presentation and biometric parameters, within the population undergoing cataract surgery in Auckland. The design is a retrospective study. Four thousand nine hundred thirty-one eyes of 3524 consecutive patients undergoing cataract surgery in Auckland Public Hospital over 18 months were included in the study. Analysis of preoperative medical records was performed. Age, gender, self-reported ethnicity, keratometry, anterior chamber depth, axial length and intraocular lens (IOL) power data were collected. Māori (4.7%) were under-represented compared with the proportion of Māori attending the eye clinic (5.5%) and in the major patient catchment area (8.2%). People of Māori, Pacific and Indian ethnicities presented at a significantly younger age (66.4, 65.9 and 67.9 years, respectively) than those of Caucasian and Asian ethnicities (76.4 and 71.3 years, respectively, P < 0.001). Advanced cataract was more likely in Pacific peoples and Māori than Caucasians. The mean axial length was longest in Asian eyes (23.83 ± 1.52 mm). The mean anterior chamber depth in the eyes of Pacific peoples (3.20 ± 0.39 mm) was significantly greater than that of Caucasians (3.09 ± 0.42 mm, P = 0.001) and Asians (3.05 ± 0.49 mm, P < 0.001). The mean IOL power in Asian eyes was 19.45D. This was significantly lower than the IOL power required by Caucasian (20.72D, P < 0.001) and Pacific ethnicities (20.61D, P = 0.001). With-the-rule astigmatism was highly prevalent in Māori and Pacific peoples, whereas in all other ethnicities, against-the-rule astigmatism was more common. This study identified significant ethnic variation in presentation for cataract surgery and ocular biometric parameters. These data may help identify potential biometric refinements and those at risk of developing ocular morbidities known to be associated with these parameters.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 08-2006
Publisher: Wiley
Date: 09-12-2016
DOI: 10.1111/CEO.12635
Publisher: Wiley
Date: 05-2003
DOI: 10.1046/J.1475-1313.2003.00107.X
Abstract: Computerised videokeratography is increasing in sophistication and accuracy. The Orbscan II Videokeratographer combines the advantages of Placido derived and slit-scanning derived topography, to acquire shape information on the posterior surface of the cornea. The purpose of this paper is to construct a model of slit-scanning elevation topography and highlight potential sources of variation in this methodology. Ray tracing calculations were performed on a defined, theoretical, spherical model to obtain a pachymetric measurement. These calculations were tested by comparing the pachymetry measurement derived from the model, over a refractive index shift from 1.376 to 1.400 with the pachymetry measurement obtained by Orbscan II, of a human eye, with an identical alteration in refractive index. The two methods of measurement differed by only 0.157 microm, suggesting that the model is a good representation of slit-scanning elevation topography, and that refractive index variations have only a minimal effect on Orbscan II pachymetry measurement.
Publisher: Springer Science and Business Media LLC
Date: 04-11-2021
DOI: 10.1038/S41598-021-01226-1
Abstract: Axonal loss is the main determinant of disease progression in multiple sclerosis (MS). This study aimed to assess the utility of corneal confocal microscopy (CCM) in detecting corneal axonal loss in different courses of MS. The results were confirmed by two independent segmentation methods. 72 subjects (144 eyes) [(clinically isolated syndrome (n = 9) relapsing–remitting MS (n = 20) secondary-progressive MS (n = 22) and age-matched, healthy controls (n = 21)] underwent CCM and assessment of their disability status. Two independent algorithms (ACCMetrics and Voxeleron deepNerve) were used to quantify corneal nerve fiber density (CNFD) (ACCMetrics only), corneal nerve fiber length (CNFL) and corneal nerve fractal dimension (CNFrD). Data are expressed as mean ± standard deviation with 95% confidence interval (CI). Compared to controls, patients with MS had significantly lower CNFD (34.76 ± 5.57 vs. 19.85 ± 6.75 fibers/mm 2 , 95% CI − 18.24 to − 11.59, P .0001), CNFL [for ACCMetrics: 19.75 ± 2.39 vs. 12.40 ± 3.30 mm/mm 2 , 95% CI − 8.94 to − 5.77, P .0001 for deepNerve: 21.98 ± 2.76 vs. 14.40 ± 4.17 mm/mm 2 , 95% CI − 9.55 to − 5.6, P .0001] and CNFrD [for ACCMetrics: 1.52 ± 0.02 vs. 1.45 ± 0.04, 95% CI − 0.09 to − 0.05, P .0001 for deepNerve: 1.29 ± 0.03 vs. 1.19 ± 0.07, 95% − 0.13 to − 0.07, P .0001]. Corneal nerve parameters were comparably reduced in different courses of MS. There was excellent reproducibility between the algorithms. Significant corneal axonal loss is detected in different courses of MS including patients with clinically isolated syndrome.
Publisher: Georg Thieme Verlag KG
Date: 26-04-2018
Abstract: This review describes the evolution of the diagnosis and treatment of keratoconus from the earliest written description to present day. The first description was provided in 1736 by Benedict Duddell who described the prominent corneas of a fourteen-year-old boy. Throughout the 19th century, a variety of surgical procedures were proposed to manage the disease, such as surgically repositioning the pupil away from the cone, iris incarceration to produce a slit-like pupil, cauterization of the cone to produce a scar, and full thickness elliptical excision of the cone. Despite the ingenuity of these procedures, many led to serious complications. In 1936, Ramon Castroviejo revolutionized surgical management by performing the first corneal transplant for keratoconus. The advent of refractive surgery in the 1990s brought about a sudden and critical need for better understanding of keratoconus and corneal ectatic disease. Topographic analysis allowed for earlier detection of keratoconus, prior to clinical signs and symptoms. Tomographic analysis provided analysis of the anterior and posterior surfaces of the cornea and allowed for even earlier detection. The Belin/Ambrosio Enhanced Ectasia Display on the Pentacam incorporates anterior and posterior elevation, pachymetric map, best fit sphere and enhanced reference surface to provide an overall “D” value that is predictive of ectatic disease. This display allows refractive providers to quickly and accurately screen potential refractive surgery candidates to identify those at risk for ectasia and early subclinical keratoconus. Corneal crosslinking was revolutionary in the treatment of keratoconus. There have been several randomized controlled trials that have found it to be safe and effective to halt ectatic progression. Crosslinking was recently approved by the FDA for progressive keratoconus. Currently, there is no clear definition of ectasia progression. Providers must be able to clearly, objectively and consistently diagnose progressive disease to institute timely treatment in the population with the greatest potential benefit. The new Belin ABCD grading system and progression analysis incorporated into the Oculus Pentacam software provides an objective way of assessing progression over time. Keratoconus diagnosis and management have grown tremendously since the first description in 1736, but there is still much to learn about keratoconus and its management.
Publisher: Springer Science and Business Media LLC
Date: 07-04-2017
DOI: 10.1038/EYE.2017.58
Publisher: American Medical Association (AMA)
Date: 09-2009
Publisher: Informa UK Limited
Date: 23-08-2018
DOI: 10.1080/02713683.2018.1510970
Abstract: The aim of this study was to perform qualitative and quantitative analyses to characterize the corneas of young, healthy sheep. Eight healthy male sheep, 10 months to 1 year of age, were included as experimental subjects. Central corneal thickness was measured using a handheld pachymeter, and an Easygraph corneal topographer provided topographic maps. Microstructural imaging of corneal layers was achieved by using the Heidelberg Retina Tomograph III Rostock Corneal Module in vivo corneal microscope (IVCM). An Ocular Response Analyzer (ORA) provided quantitative measurements of intraocular pressure (IOP), corneal hysteresis (CH), and corneal resistance factor. Tissue histology and immunohistochemistry were carried out to obtain detail on the corneal layers. Light microscopy and immunohistochemical labeling revealed a stratified epithelium, a limbus with numerous limbal crypts, a thick basement membrane, a thin Bowman's layer, a thick corneal stroma with a dense population of keratocytes, and a thick, hyper-reflective Descemet's membrane. Using IVCM, the cell density of the basal layer was noted to be significantly higher than that of other epithelial cell types. The density of keratocytes was significantly higher (P value = 0.0223) in the anterior compared to the posterior stroma. The endothelial cells were organized in a characteristic honeycomb pattern. The mean and standard deviation values for central corneal pachymetry were 623.14 ± 19.5 μm and 616.37 ± 34.87 μm for the left and right eyes, respectively. ORA-derived mean values for IOP The anatomical and clinical characteristics of the sheep cornea, as outlined in this study, make the sheep a suitable and relevant model for corneal research. This study provides researchers with important data on the suitability of sheep as a model for ophthalmic experiments.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 07-2016
Publisher: Informa UK Limited
Date: 26-08-2014
DOI: 10.3109/09286586.2014.949781
Abstract: To report the spectrum of retinopathy at first presentation to photoscreening services, to determine the proportion of patients that present with sight-threatening diabetic retinopathy (STDR), and to raise awareness of the burden of diabetic eye disease in Fiji. This retrospective observational cohort study used data from the initial visit of all new patients presenting to the diabetes retinal screening service at the Pacific Eye Institute in Fiji over the 3-month period between July and September 2012. Patients were assessed using a detailed questionnaire regarding diabetes type, duration of disease, medications, complications and co-morbidities, and blood sugar control. Patients subsequently underwent non-mydriatic fundus photography according to Pacific diabetes retinal screening guidelines. Images were graded at the time of acquisition, and data were entered onto a computerized database. For the purposes of this study, information regarding retinopathy grading, visual acuity and patient demographics was used. A total of 522 new patients were screened over the 3-month period. STDR was observed in 27% of patients, with 15% observed to have bilateral STDR. Diabetes control was generally poor. Blindness and visual impairment were observed in 2.7% and 6.7% of the cohort, respectively. Severe and advanced diabetic retinopathy was present in this population presenting to screening. This was observed 4 years after the formal expansion of the screening services and reflects the high prevalence of diabetes in the population. The need for increased public awareness and greater resource allocation into diabetes and its complications is emphasized.
Publisher: BMJ
Date: 08-02-2016
DOI: 10.1136/BJOPHTHALMOL-2015-307604
Abstract: Wound dehiscence is an uncommon but significant complication following keratoplasty. This study analysed the incidence, risk factors, clinical features and outcomes of traumatic wound dehiscence following keratoplasty. Retrospective case series at a major tertiary care centre in New Zealand. Records of all consecutive patients who underwent penetrating keratoplasty (PK, n=1163) or deep anterior lamellar keratoplasty (DALK, n=131) between 2000 and 2014 and theatre logs were reviewed to identify all cases of traumatic dehiscence. Main outcome measures include: incidence of traumatic dehiscence, aetiology/associations and final best corrected visual acuity. Thirty eyes in 29 patients were identified as having a traumatic wound dehiscence following PK. No cases of wound dehiscence were identified following DALK. The incidence rate of traumatic graft dehiscence among keratoplasties performed at our centre was 2.3 per 1000 person-years. The major causes of trauma were: accidentally being struck by an object (33%) or child (13%), intentional trauma (20%) and falls (13%). Wound rupture occurred at a median of 22 months (range 6 weeks to 32 years) following keratoplasty, most frequently (37%) within the first year. Keratoplasty decompensation occurred in 17 eyes (57%). Final best corrected visual acuity was ≥6/15 in 11 eyes (37%), ≤6/60 in 14 eyes (47%) and no perception of light in 5 eyes (17%). Traumatic wound dehiscence may occur following minor trauma, even years after PK and frequently causes severe vision loss. Patients should be advised of this longer term risk and protective eye-wear should be encouraged by eye care providers.
Publisher: Springer Science and Business Media LLC
Date: 24-02-2006
Abstract: To establish and quantify the in vivo confocal microscopic features of moderate to advanced keratoconus. Nineteen keratoconus subjects were catergorised using Orbscan-derived corneal apex power and pachymetry as exhibiting moderate (n=7) and advanced (n=12) keratoconus. Control subjects included 23 noncontact lens wearers (Group A) and 15 contact lens wearers (Group B). All subjects underwent Confoscan slit scanning in vivo confocal microscopy. Compared with Group A (4912+/-434 cells/mm(2)), basal epithelial density was significantly lower in both moderate (4592+/-414 cells/mm(2), P<0.05) and advanced keratoconus (4530+/-596 cells/mm(2), P=0.01). In comparison to Group A (761+/-118 cells/mm(2)), anterior stroma keratocyte density was significantly greater in both moderate keratoconus (883+/-111 cells/mm(2), P=0.001) and advanced keratoconus (952+/-122 cells/mm(2), P<0.001). Compared to Group A (504+/-80 cells/mm(2)) posterior stroma keratocyte density was also significantly greater in advanced keratoconus (599+/-97 cells/mm(2), P<0.001) and posterior stromal keratocyte density appeared to increase with increasing severity of keratoconus (P<0.05). However, comparing control Groups A and B, contact lens wear per se, was associated with significantly reduced (P=0.000) keratocyte density in the anterior stroma (609+/-66 cells/mm(2)) and demonstrated a trend (P=0.056) in the posterior stroma (470+/-63 cells/mm(2)). Keratoconic corneas (429+/-72 microm) were significantly thinner than control Groups A (508+/-77 mm) and B (495+/-80 microm). The presence of keratoconus did not affect the endothelial cell density (P=0.54). In vivo confocal microscopy can provide insight into the microstructural changes that occur in keratoconus.
Publisher: Informa UK Limited
Date: 09-2013
DOI: 10.1111/CXO.12011
Abstract: We localised amino acids in the mid-peripheral aged human retina and a retina that had undergone radiation treatment 10 years earlier. The distribution pattern of glutamate, γ-amino butyric acid (GABA), glycine, glutamine and taurine, reflected patterns established in the primate retina. The retina that had undergone radiation exposure displayed both anatomical and neurochemical remodelling. The proximal retina comprised around 40 to 45 per cent of the total retina and neuronal kinesis and aberrant neuronal projections were also present. Amino acid neurochemistry was strikingly different with Müller cells displaying GABA loading, glycinergic neurons displaced and displaying a very high level of glycine labelling. We conclude that radiation exposure triggered these changes in the human retina and likely reflects general remodelling of structure and function following ischaemic damage to endothelial cells.
Publisher: Elsevier BV
Date: 05-2008
DOI: 10.1016/J.OPHTHA.2007.04.067
Abstract: Keratoconus is a form of progressive noninflammatory corneal ectasia. Although abnormalities have been documented at every level of the keratoconic cornea, the exact underlying pathophysiologic process remains unknown. This study aimed to determine the keratocyte density in human corneas with keratoconus imaged by laser scanning in vivo confocal microscopy. Prospective cross-sectional study. Thirty-six eyes of 26 subjects with keratoconus compared with 33 eyes of 33 control subjects. Subjects were assessed via ophthalmic examination, computed topography, and laser scanning in vivo confocal microscopy. Anterior and posterior stromal keratocyte density. Mean age was 34.7+/-12.1 years in the control group, 38.4+/-11.0 years in the keratoconic with no contact lens wear group, and 38.5+/-10.3 years in the keratoconic with contact lens wear group. No significant difference was noted in age or gender between the groups. Mean keratocyte density in the control group was 786+/-244 cells/mm(2) in the anterior stroma and 293+/-35 cells/mm(2) in the posterior stroma. Anterior keratocyte density was higher than posterior keratocyte density (P<0.001). Anterior keratocyte density was significantly lower in contact lens-wearing keratoconic subjects in comparison with controls (463 vs. 786 cells/mm(2) P<0.001). Posterior keratocyte density was significantly lower in keratoconic subjects with no contact lens wear (236 vs. 293 cells/mm(2) P<0.001) and in keratoconic subjects with contact lens wear (208 vs. 293 cells/mm(2) P<0.001). In subjects with keratoconus, anterior keratocyte density correlated with central corneal thickness (r = 0.426, P = 0.012) and inversely with steepest keratometry values (r = -0.383, P = 0.028). Keratocyte density is significantly lower in subjects with keratoconus, and the decline in keratocyte density correlates with indices of disease severity. In vivo confocal microscopy offers the opportunity to study early microstructural changes in the keratoconic cornea.
Publisher: Wiley
Date: 29-07-2003
DOI: 10.1046/J.1442-9071.2003.00678.X
Abstract: To determine the attitudes to research and research training among ophthalmologists and ophthalmology trainees in New Zealand. A structured, self-administered questionnaire was devised and after preliminary validation a postal survey was sent to all ophthalmologists and ophthalmology registrars and fellows in New Zealand. A total of 82 replies were received from 115 questionnaires sent out a response rate of 71.3%. An overwhelming majority found research to have benefited their education, clinical practice and career 67.1% of the respondents intended to do research in the future. Although a majority (56.4%) felt research to be beneficial to ophthalmology training, 42.3% felt research would be of limited or no benefit when selecting candidates for vocational training. However, 97.5% of respondents felt that ophthalmology trainees should undertake some form of research during training, with most supporting small studies or case reports (44.4%) or a short structured training course in research (42.0%). Interestingly, 86.6% felt that research methodology and data analysis should be taught in a structured fashion with most supporting courses or seminars of a few weeks duration during the vocational training period. Many ophthalmologists felt inadequately equipped or trained to mentor and supervise trainees undertaking research and 41.5% of consultant ophthalmologists felt further training to fulfil this role would be beneficial. This survey suggests that New Zealand ophthalmologists generally approve of and support a place for research, possibly of a more structured design, during ophthalmology training.
Publisher: BMJ
Date: 15-09-2017
DOI: 10.1136/BJOPHTHALMOL-2016-309021
Abstract: To report the 25-year longitudinal trends in indications and corneal transplantation techniques in New Zealand. Statistical analysis of prospectively acquired New Zealand National Eye Bank (NZNEB) electronic database from 1991 to 2015 inclusive. Subjects were recipients of corneal transplants in 62 centres supplied by the NZNEB. Main outcome measures were indications, recipient age and transplantation techniques. From January 1991 to December 2015, NZNEB supplied tissue for 5574 corneal transplants, increasing annually from 89 (1991) to 290 (2015). Penetrating keratoplasty remained the most commonly performed technique throughout the 25-year period, although it decreased from 98.9% of all transplants in 1991 to 60.3% in 2015. There was a corresponding increase in deep anterior lamellar and endothelial keratoplasty over the most recent decade from 2.5% to 7.2% and 4.9% to 31.4%, respectively. Keratoconus remained the leading indication for keratoplasty through to 2015 (34.5%). Regrafts (23.1%) and Fuchs endothelial corneal dystrophy (17.0%) have become more common indications, while bullous keratopathy has become less common (10.8%). There was a bimodal distribution in age with peaks at 20-29 and 60-79 years. There was a reduction in recipients under age 40 and corresponding increase in the percentage of recipients aged 40-69. Changing indications and increasing uptake of lamellar keratoplasty have been significant international trends over the last 25 years. However, New Zealand's corneal disease and population characteristics create unique longitudinal trends, with keratoconus remaining the leading indication and penetrating keratoplasty the leading technique from 1991 to 2015.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 04-2007
DOI: 10.1016/J.JCRS.2006.12.019
Abstract: We report a case of true exfoliation of the crystalline lens in a 53-year-old baker who presented with reduced vision due to cataract. Phacoemulsification cataract surgery with intraocular lens implantation was performed, and the anterior capsule was analyzed histologically. Preoperative clinical and anterior segment optical coherence tomography observations are presented, with a description of the modified phacoemulsification technique and histopathology. A possible mechanism of pathogenesis is proposed in the context of the histopathology.
Publisher: Wiley
Date: 04-2012
Publisher: BMJ
Date: 27-03-2007
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 07-2005
DOI: 10.1097/01.ICO.0000153560.12773.EB
Abstract: This report describes the clinical and in vivo microstructural features of the cornea in a case of Maroteaux-Lamy syndrome. A 17-year-old female with Maroteaux-Lamy syndrome was examined by slit-l biomicroscopy, Orbscan II slit-scanning elevation topography, and in vivo confocal microscopy. Slit-l biomicroscopy revealed bilateral, altered corneal transparency involving the posterior half of the stroma. Funduscopy revealed bilateral small, crowded optic discs, and radial macula retinal folds. On in vivo confocal microscopy, the middle and posterior stroma were clearly visualized and exhibited well-defined, unusually shaped keratocytes. These cells contained single or multiple hyporeflective regions with well-defined borders that ranged from 1 to 11.6 microm in diameter. These abnormal keratocytes were particularly abundant in the posterior stroma and sparse in the anterior stroma. This is the first case of Maroteaux-Lamy syndrome in which altered corneal transparency has been imaged by in vivo confocal microscopy and macula retinal folds have been described.
Publisher: Elsevier BV
Date: 04-2016
DOI: 10.1016/J.OPHTHA.2015.12.008
Abstract: Corneal dystrophies are a genetically heterogeneous group of disorders. We previously described a family with an autosomal dominant epithelial recurrent erosion dystrophy (ERED). We aimed to identify the underlying genetic cause of ERED in this family and 3 additional ERED families. We sought to characterize the potential function of the candidate genes using the human and zebrafish cornea. Case series study of 4 white families with a similar ERED. An experimental study was performed on human and zebrafish tissue to examine the putative biological function of candidate genes. Four ERED families, including 28 affected and 17 unaffected in iduals. HumanLinkage-12 arrays (Illumina, San Diego, CA) were used to genotype 17 family members. Next-generation exome sequencing was performed on an uncle-niece pair. Segregation of potential causative mutations was confirmed using Sanger sequencing. Protein expression was determined using immunohistochemistry in human and zebrafish cornea. Gene expression in zebrafish was assessed using whole-mount in situ hybridization. Morpholino-induced transient gene knockdown was performed in zebrafish embryos. Linkage microarray, exome analysis, DNA sequence analysis, immunohistochemistry, in situ hybridization, and morpholino-induced genetic knockdown results. Linkage microarray analysis identified a candidate region on chromosome chr10:12,576,562-112,763,135, and exploration of exome sequencing data identified 8 putative pathogenic variants in this linkage region. Two variants segregated in 06NZ-TRB1 with ERED: COL17A1 c.3156C→T and DNAJC9 c.334G→A. The COL17A1 c.3156C→T variant segregated in all 4 ERED families. We showed biologically relevant expression of these proteins in human cornea. Both proteins are expressed in the cornea of zebrafish embryos and adults. Zebrafish lacking Col17a1a and Dnajc9 during development show no gross corneal phenotype. The COL17A1 c.3156C→T variant is the likely causative mutation in our recurrent corneal erosion families, and its presence in 4 independent families suggests that it is prevalent in ERED. This same COL17A1 c.3156C→T variant recently was identified in a separate pedigree with ERED. Our study expands the phenotypic spectrum of COL17A1 disease from autosomal recessive epidermolysis bullosa to autosomal dominant ERED and identifies COL17A1 as a key protein in maintaining integrity of the corneal epithelium.
Publisher: MDPI AG
Date: 03-01-2023
Abstract: Corneal confocal microscopy has not previously been performed in penguins, despite recognition of its unusually flat shape. To identify features that the penguin shares with other birds and or mammals and those specific to penguins, we undertook confocal microscopic examination of two little (Eudyptula minor), four gentoo (Pygoscelis papua) and five king (Aptenodytes patagonicus) penguin corneas. Transmission electron microscopy was performed on one gentoo and one king penguin, for finer details. Features shared with other higher vertebrates included a five-layered cornea and a similar limbus. Typically avian were a lower density of stromal cells, a more regular arrangement of collagen bands and an absent basal nerve plexus. Features unique to penguins included a flattened superficial epithelium (king penguin), stromal myofibroblasts (all) and an irregular endothelium (little penguin). Other features uniquely identified by confocal microscopy in birds include epithelial and stromal nerves, guttata and stromal imprints on Descemet’s membrane. Transmission electron microscopy identified a lack of wing cells (king penguin), greater posterior collagen lamellae thickness (gentoo penguin) and significantly less interlacing of collagen lamellae in the central cornea (king and gentoo). Most of these unique features are yet to be explained, but some could be adaptations to ing.
Publisher: Wiley
Date: 06-2003
Publisher: Public Library of Science (PLoS)
Date: 21-05-2021
DOI: 10.1371/JOURNAL.PONE.0248659
Abstract: To compare the repeatability and agreement in biometric measurements using Spectral Domain Anterior Segment OCT (AS-OCT, REVO-NX, Optopol) and Scheimpflug tomography (Pentacam-AXL, Oculus) in keratoconus. Prospective case series at a university hospital tertiary center. Axial length (AL), anterior chamber depth (ACD), central corneal thickness (CCT), and thinnest corneal thickness (TCT) were measured using both devices in patients with keratoconus. Three groups were analyzed: eyes with no prior crosslinking or contact lens wear (Group A), eyes with prior crosslinking (Group B), and eyes with prior contact lens wear (Group C). Repeatability and agreement of measurements were analyzed. The study comprised of 214 eyes of 157 subjects. In Group A (n = 95 eyes), Group B (n = 86 eyes), and Group C (n = 33 eyes), intraclass correlation coefficient (ICC) was higher than 0.90 for all examined parameters, except for ACD readings in Group A with the REVO-NX (ICC = 0.83). Differences in ACD, TCT, and CCT were significantly different between the two devices for Groups A, B and C (p .05). AL measurements differed significantly in Groups A and B (p .05) but not in Group C (p = 0.18). Repeatability did not vary significantly between Groups A, B, or C in any parameter with both devices (p .05). There was poor agreement between the two devices across all parameters (p .05). Both devices demonstrated good repeatability but poor agreement across AL, ACD, CCT and TCT measurements. There was no significant difference in repeatability in virgin eyes compared to eyes with prior crosslinking or contact lens wear, however, the interchangeable use of the two devices is not recommended.
Publisher: Association for Research in Vision and Ophthalmology (ARVO)
Date: 08-09-2014
Abstract: Mutations in the zinc finger protein gene ZNF469 cause recessive brittle cornea syndrome, characterized by spontaneous corneal perforations. Genome-wide association studies (GWAS) have implicated common variants in this gene as a determinant for central corneal thickness (CCT). We investigated the contribution of ZNF469 in a s le set of keratoconus patients. Forty-three patients with keratoconus (49% Māori or Pacific [Polynesian]) were recruited. If a family history was present, family members were recruited. Participants underwent comprehensive examination, and a DNA s le was collected. Mutational analysis of ZNF469 was undertaken using Sanger sequencing, including an ancestrally matched Polynesian control population. Bioinformatic databases of exome variation and protein prediction software were used to determine presence and frequency and the pathogenicity for each observed change. Fourteen nonsynonymous missense single nucleotide polymorphisms (SNPs) were observed in ZNF469. Of the 43 probands, at least one probable disease-causing variant was detected in 20 (46%) (16/32 sporadic, 4/11 familial) and two variants in 5 (11.6%) (3/32 sporadic, 2/11 familial). Only heterozygous changes segregated with disease. Three "deleterious" changes observed in the Polynesian controls were removed from analysis therefore pathogenic variants occurred in 10/43 (23.3%). Rare missense mutations in ZNF469, predicted to be pathogenic, occurred heterozygously, at a frequency of 23% in a keratoconus population. ZNF469 is associated with CCT in GWAS and is therefore likely to play a role in the synthesis and/or organization of corneal collagen fibers. The pathogenic changes observed either genetically predispose toward a "thin" cornea, which then becomes keratoconic, or are directly pathogenic.
Publisher: Springer Science and Business Media LLC
Date: 03-03-2005
DOI: 10.1007/S00417-004-0982-Z
Abstract: Deposits in the cornea and lens are a known complication of long-term chlorpromazine therapy. A 59-year-old woman had previously taken chlorpromazine for 20 years with doses up to 1,200 mg/day, with a mean dose of 400 mg/day. She presented with gradual onset of blurred vision in her left eye. Slit-l biomicroscopy revealed multiple fine creamy-white deposits on her corneal endothelium and anterior crystalline lens capsule bilaterally. In vivo confocal microscopy of the cornea identified irregular hyper-reflective deposits on the posterior surface of the endothelium. The deposits varied from 1 microm to 70 microm in diameter and had well-defined edges. Endothelial morphology was otherwise normal bilaterally. This is the first report of in vivo confocal imaging of deposits resulting from long-term chlorpromazine use. Microstructural analysis of the corneal endothelium reveals that there were no abnormalities in cellular morphology resulting from these deposits.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 2004
Publisher: Elsevier BV
Date: 05-2014
DOI: 10.1016/J.AJO.2014.01.017
Abstract: To summarize the current concepts and recent literature regarding the epidemiology, pathogenesis, imaging modalities, and treatment of acute hydrops in keratoconus. Perspective. Review and synthesis of selected literature, with interpretation and perspective. Acute corneal hydrops is an incompletely understood complication of keratoconus, characterized by marked corneal edema caused by a break in Descemet membrane, allowing aqueous to enter the corneal stroma and epithelium. Although usually self-limiting, with clinical signs of edema typically resolving after 3 months, it often leaves a vision-impairing scar, necessitating and expediting the need for corneal transplantation. Studies have identified risk factors for developing acute hydrops. Modern imaging modalities such as ultrasound biomicroscopy, anterior segment optical coherence tomography, and in vivo confocal microscopy have enlightened us to the microstructural changes that take place during acute hydrops, the factors that influence its duration, and sequelae. Newer treatment regimens have seen a reduction in the duration of corneal edema during acute hydrops, and have improved the survival of corneal grafts after transplantation for resolved hydrops. Effective management of acute corneal hydrops in keratoconus is based on recognizing and addressing the risk factors, treating the acute event effectively and promptly to reduce the duration of edema and its complications, and, ultimately, successful corneal transplantation with acceptable long-term graft survival rates. Improved in vivo imaging of the cornea during acute hydrops has led to an enhanced understanding of the pathogenesis and ultrastructural changes of the condition, and in turn has resulted in improved management of the disease.
Publisher: Wiley
Date: 02-09-2019
DOI: 10.1111/CEO.13614
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 05-2002
DOI: 10.1016/S0886-3350(02)01234-8
Abstract: To determine the relative importance of patients' motives for having laser in situ keratomileusis (LASIK) for myopia. The Corneal Diseases and Excimer Laser Research Unit, University of Dundee, Ninewells Hospital and Medical School, Dundee, Scotland. Twenty-one cards printed with potential reasons for having LASIK and 3 blank cards for respondents to include additional motives were posted to 71 patients who had myopic LASIK. The cards were ranked by each respondent in order of personal importance and returned for analysis. The response rate was 77.5%. The mean age of the 19 male and 37 female respondents was 41.7 years +/- 9.3 (SD) and the mean preoperative spherical equivalent, -9.26 +/- 4.58 diopters. The primary reasons for seeking treatment (percentage of respondents ranking topic within the top 5) were improvement of unaided social vision (69.1%), intolerance to spectacles/contact lenses (65.5%), and freedom from spectacles/contact lenses (61.8%). Almost 70% of respondents ranked 1 of these reasons as the most important. General inconvenience of spectacles/contact lenses and the desire to pursue sports and leisure activities also ranked high (52.7% and 36.4%, respectively). Consistent with previous work, better unaided vision, combined with the inconvenience of or intolerance to spectacles or contact lenses, provided the main incentives to have LASIK for myopia, while improved cosmesis was relatively unimportant (29.1%). The results of this study will allow the design of satisfaction questionnaires that are better directed toward establishing satisfaction of specific, relevant functional and psychological aspects of refractive surgery that are important to patients.
Publisher: Springer Science and Business Media LLC
Date: 04-07-2019
Publisher: Medknow
Date: 07-2011
Publisher: BMJ
Date: 04-2005
Publisher: Wiley
Date: 08-09-2020
DOI: 10.1111/CEO.13852
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 10-2005
Publisher: Informa UK Limited
Date: 03-2013
DOI: 10.1111/CXO.12006
Abstract: Although first described more than 150 years ago, keratoconus is still an enigmatic disease that remains an area of wide-ranging, dynamic, international research. This review considers data from New Zealand/Aotearoa, where keratoconus is both relatively common and extensively studied. New Zealand researchers have made several significant contributions to the international literature in this field, including identifying a higher prevalence of keratoconus in New Zealand per se and within Maori and Polynesian populations compared to many international studies. As reported in other studies, a higher proportion of asthma, allergy and eczema as potential risk co-factors are present in New Zealand subjects with keratoconus compared with estimates from the general population. The rates of family history of keratoconus are typically higher than those reported internationally, with higher rates in Asian, Pacific and Maori ethnicities. Interestingly, such a positive family history has been associated with less severe keratoconus on computerised topographic analysis. Investigations of corneal microstructure have revealed dramatic alterations in the keratoconic cornea, with reduced density and abnormal morphology of the corneal sub-basal nerve plexus and decreased keratocytic density. Laboratory studies of keratoconic corneal buttons have also furthered our understanding of the pathophysiology of this disease, demonstrating elevated levels of cathepsin enzymes and localised disruptions in Bowman's layer with incursion of cellular processes from anterior keratocytes. Over the past two decades keratoconus has consistently remained the leading indication for corneal transplantation in New Zealand, accounting for over 40 per cent of cases. Indeed, New Zealand appears to have the highest reported proportion of transplantation surgery for keratoconus worldwide. Current and future studies of keratoconus in New Zealand highlight an emphasis on elucidating the genetics of, and investigating novel therapeutic interventions for, this relatively common corneal disease.
Publisher: Informa UK Limited
Date: 2019
DOI: 10.1111/CXO.12803
Abstract: Common paediatric perimetry techniques require central fixation and subjective responses, which may be challenging for young or cognitively impaired children. The Saccadic Vector Optokinetic Perimeter (SVOP) was designed to overcome these challenges by using infra-red eye tracking to assess the visual field. This study assessed the clinical feasibility of SVOP in children without visual impairment, comparing it to current paediatric techniques, and in children with visual impairment. Participants were recruited into two cohorts: children without visual impairment (visual acuity ≥ 6/7.5) and children with visual impairment (visual acuity ≤ 6/18). Children without visual impairment attempted the Goldmann perimeter, confrontation method, and SVOP. Children with visual impairment attempted SVOP, when clinically indicated, as part of a full ophthalmic assessment. Visual field results and test length were recorded. Twenty-three children without visual impairment (4-14 years old) attempted all three visual field assessments. Full results were recorded for 91 per cent of children with SVOP, 87 per cent with Goldmann, and 100 per cent with confrontation SVOP was significantly faster than Goldmann (p < 0.001) and confrontation (p = 0.003). Thirty-five children with visual impairment (3-19 years old) with visual acuity ranging from 6/9.5 to worse than 6/360 (mean of 0.8 ± 0.4 logMAR) attempted SVOP, with 26 children able to complete SVOP. This is the largest study to date of the clinical applicability of SVOP in children without visual impairment, as well as assessing the utility of SVOP in children with visual impairment. Further research is needed to assess the accuracy of SVOP in a range of paediatric ocular disorders. SVOP may potentially offer a visual field assessment method for children previously unable to complete current paediatric perimetry techniques.
Publisher: Wiley
Date: 03-2020
DOI: 10.1111/CEO.13738
Publisher: Wiley
Date: 26-02-2020
DOI: 10.1111/CEO.13739
Publisher: Wiley
Date: 08-10-2015
DOI: 10.1111/CEO.12409
Publisher: Informa UK Limited
Date: 07-2014
DOI: 10.1111/CXO.12121
Abstract: Medical tourism is the practice of travelling overseas for surgery. We describe a patient with low myopia who underwent laser in situ keratomileusis (LASIK) while on holiday in India. She presented to local hospital eye services six weeks post-LASIK with discomfort and reduced vision. She reported three previous LASIK flap lifts in the right eye. Clinical assessment, optical coherence tomography and confocal microscopy demonstrated moderate epithelial ingrowth and reduced visual acuity. Epithelial ingrowth after LASIK may be associated with visual impairment and management is determined by location, magnitude and effect on vision. LASIK tourism may mean patients are less well-informed of risks and lose continuity of professional care.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 03-2015
Publisher: Wiley
Date: 06-2001
DOI: 10.1046/J.1442-9071.2001.00393.X
Abstract: The purpose of this study was to demonstrate microstructural differences between clinically similar, but aetiologically different, cases of corneal oedema in four subjects. In vivo confocal microscopy highlighted oedema of the basal epithelium, prominent nerve-keratocyte interactions, and typical 'epithelialization' of the endothelium in a case of iridocorneal endothelial syndrome however, a similar microstructural appearance was observed in a case of presumed herpetic disciform keratitis. The latter diagnosis was subsequently revised on this basis. Confocal examination of Fuchs' endothelial dystrophy demonstrated oedema of the basal epithelium, prominent wing cells, anterior stromal alterations, fibrosis of Descemet's membrane and a typical 'strawberry' appearance of the endothelium. In contrast, in vivo microstructural examination of bilateral keratoconus with hydrops confirmed oedema mainly involving the epithelium and anterior stroma. In vivo confocal microscopy allows the clinician to observe the living cornea at a microstructural level and to better diagnose and differentiate borderline or unusual cases of corneal oedema.
Publisher: Medknow
Date: 2019
Publisher: Elsevier BV
Date: 04-2011
Publisher: Elsevier BV
Date: 03-2017
DOI: 10.1016/J.AJO.2016.12.003
Abstract: To assess the repeatability and agreement of keratometry and pachymetry measurements obtained using 3 tomographers in eyes with keratoconus. Reliability analysis. setting: Institutional. Fifty eyes of 50 participants with keratoconus. observational procedure: Steep keratometry, flat keratometry, central corneal thickness (CCT), and thinnest corneal thickness (TCT) measurements using Galilei, Orbscan II, and Pentacam HR. Repeatability was assessed using within-subject standard deviation (S For all studied parameters, ICC was >0.97 with the least repeatable measurements obtained using Orbscan II. Mean steep keratometry values were similar while mean flat keratometry values were significantly different between all devices. The Galilei and Pentacam HR had the lowest 95% LoA for both CCT and TCT. There were no significant differences in mean CCT between Galilei and Pentacam HR. Mean Orbscan II CCT measurements were not significantly different overall but had wide 95% LoA with Pentacam HR (-47.95 to 58.09 μm) and Galilei (-43.70 to 53.91 μm). Mean Orbscan II CCT measurements were significantly lower when an acoustic factor of 0.92 was applied (-33.6 μm vs Pentacam HR, P < .001 -33.6 μm vs Galilei P < .001). Keratometric and pachymetric measurements of keratoconic eyes obtained by Galilei, Orbscan II, and Pentacam were disparate. Measurements were less repeatable with Orbscan II compared with Pentacam HR and Galilei, although overall repeatability was high for all instruments.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 11-2005
DOI: 10.1016/J.JCRS.2005.10.021
Abstract: Understanding the key elements that increase the likelihood of project success is fundamental for those embarking on research. The first article in this series placed scientific journals in perspective in relation to Journal Impact Factors and citation indices. This second article in a series primarily aimed at those commencing research, particularly in the area of ophthalmology and vision science, delineates the interrelated components that are required to complete a research project. Successful research projects seldom emerge from serendipitous observation, and most evolve through a combination of inspiration, careful planning, and a great deal of industry. Beginning researchers must first be clear about their reason(s) for pursuing research and should identify potential mentors and collaborators at the outset. This article discusses methods of identifying suitable projects and mentors. Ten component areas necessary to complete a research project are addressed, with reference to relevant published literature, under the following topic areas: mentors and collaborators finding a research topic confirming suitability of the topic defining the research question developing the hypothesis key considerations in study design threats to study validity study s le size benefits and limitations of clinical science completing to publication. This guide is intended to be applicable to all embarking on research, but particularly to those with an interest in the visual system. The final 3 articles in this series will deal with writing a research paper to publication standard, working successfully with the journal review process, and refining electronic literature searches.
Publisher: Springer Science and Business Media LLC
Date: 25-03-2022
DOI: 10.1038/S41433-022-02017-2
Abstract: Iris melanoma, a rare intraocular malignancy, represents the smallest subgroup of uveal melanoma. This first, comprehensive study of iris melanocytic lesions in the high ultraviolet environment in New Zealand/ Aotearoa (NZ) examines diagnosis, management and outcomes. Retrospective study of iris melanocytic tumours referred to tertiary referral centres in Auckland, NZ, over 20 years (1999-2018). Data analysed include demographics, tumour characteristics, histology, genetic analyses, treatment modalities, recurrence, metastasis, 5-year and overall survival. Cohort (N = 51) was predominantly NZ European (98.0%) with no indigenous Māori, or Pasifika. Median age at presentation was 58 years. Tumours involved a median of two clock hours of iris. The posterior tumour margin extended to the anterior chamber angle in 22 patients (45.8%). Management included initial observation 54.9%, iridectomy/excision biopsy 29.4%, irido-cyclectomy 7.8%, plaque radiotherapy 7.8%, proton beam radiotherapy 7.8%, and ultimately enucleation 17.6%. Histology was performed in 19 cases (37%) with 16 confirmed melanomas (84%). Mean follow-up 4.2 years with median visual acuity of 6/7.5 two years post intervention. Melanoma-related metastasis and mortality occurred in two cases with five-year melanoma-related mortality of 2.0%. In a climate with high ultraviolet exposure iris melanocytic tumours occurred almost exclusively in NZ Europeans, however, the majority of cases were category T1, possibly reflecting early diagnosis in the NZ health system. Nonetheless, % underwent surgery or radiotherapy, often utilising more than one modality. A high index of suspicion and early referral of iris melanocytic lesions should be considered in regions with high UV exposure.
Publisher: Wiley
Date: 11-10-2020
DOI: 10.1111/CEO.13861
Publisher: Wiley
Date: 11-09-2020
DOI: 10.1111/CEO.13620
Publisher: Wiley
Date: 10-2013
DOI: 10.1111/ANS.12351
Publisher: Informa UK Limited
Date: 05-2014
DOI: 10.1111/CXO.12118
Abstract: Keratoconus manifests as a conical protrusion of the cornea and is characterised by stromal thinning. This causes debilitating visual impairment, which may necessitate corneal transplantation. Hypothetically, many of the pathological features in keratoconus may be manifestations of defects in wound healing however, as the pathobiology remains unclear, therapeutic targets related to disease mechanisms are currently lacking. This study investigated the protein expression of cytokines which may control stromal wound healing and the effect of an induced secondary injury (SI) on stromal cells from ex vivo human keratoconus and control corneas. Total protein was extracted from stromal cells from human keratoconic and non-keratoconic central corneas (n = 12) with (+SI) and without (-SI) an ex vivo corneal incision wound. The levels of interleukin 1 alpha (IL-1α), fibroblast growth factor 2 (FGF-2), nerve growth factor beta (β-NGF), insulin-like growth factor 1 (IGF-1), tumour necrosis factor alpha (TNF-α), epidermal growth factor (EGF), transforming growth factor beta 1 (TGF-β1), platelet-derived growth factor (PDGF) and hepatocyte growth factor (HGF) were quantified using chemiluminescence-based immunoarrays. In stromal cells from -SI keratoconic corneas (compared with -SI normal corneas), the levels of IL-1α, IGF-1, TNF-α and TGF-β1 were increased and the levels of HGF and β-NGF were reduced. These alterations were also observed in +SI non-keratoconic corneas (compared with -SI non-keratoconic corneas). In stromal cells from +SI keratoconic corneas (compared with -SI keratoconic corneas), the quantities of IL-1α, FGF-2, TNF-a, EGF, TGF-a1 and PDGF were decreased. The repair-modulating milieu in keratoconic corneas appears comparable to that in wounded normal corneas. Moreover, wounded keratoconic corneas may be less capable of orchestrating a normal reparative response. These novel findings may improve our understanding of the pathobiology and may facilitate the identification of potential biological targets and therapeutic agents to advance the clinical management of this disorder.
Publisher: Springer Science and Business Media LLC
Date: 20-03-2009
DOI: 10.1038/EYE.2008.413
Abstract: To determine the incidence of postkeratoplasty intraocular pressure (IOP) elevation in the eyes of subjects with keratoconus and establish the relationship between IOP and corticosteroid administrations in this population. Following strict inclusion/exclusion criteria, a retrospective analysis was performed on a consecutive series of penetrating keratoplasties performed for keratoconus observing a standardised surgical and postoperative regimen in Auckland, New Zealand. Patient demographics, ocular, medical, and family history, and pre- and postoperative data were recorded until 12 months postkeratoplasty. In all, 57 eyes of 48 patients were included-31% New Zealand Europeans, 42% Pacific people, 15% Maori, and 12% other. Eighteen eyes (32%) of 17 patients (35%) exhibited elevated IOP and 12 (21%) eyes exhibited moderate-to-severe elevation of IOP. IOP elevation occurred 3-6 months postkeratoplasty in 78% of eyes. Elevated IOP was significantly less common in Maori and Pacific peoples (P=0.02). All eyes except one required reduction/cessation of corticosteroids to normalise IOP. The incidence of presumed steroid-related postkeratoplasty IOP elevation, in 35% of subjects with keratoconus, is markedly higher in this New Zealand study than previously reported in the US and UK studies. Further clinical and genetic analysis of associations between keratoconus and steroid-induced IOP elevation and glaucoma might improve our current understanding of this condition.
Publisher: Wiley
Date: 18-03-2020
DOI: 10.1111/CEO.13748
Publisher: BMJ
Date: 09-2003
Abstract: To identify key risk factors and the management and outcome of severe infective keratitis leading to public hospital admission in New Zealand. Over a 2 year period, all admissions of presumed infective keratitis to Auckland Hospital were identified. The clinical records of all 103 cases were retrospectively reviewed with respect to clinical features, risk factors, management, and outcomes. The mean time from first symptoms or signs and presentation to hospital was 8.9 (SD 15.5) days. The majority of subjects, 88%, had at least one of the risk factors commonly associated with infective keratitis including previous ocular surgery (30%), contact lens wear (26%), topical corticosteroid use (25%), and ocular trauma (24%). Corneal scraping was performed in 92% and of a total of 105 scrapes, 71% were positive. Bacteria were isolated in all these cases, the majority being Gram positive organisms (72%). The most common isolates identified were coagulase negative Staphylococcus (16%), Propionibacterium acnes (14%), Staphylococcus epidermidis (11%), and Streptococcus pneumoniae (9%). In addition, yeasts were isolated in 5%, fungi in 4%, virus in 2%, and chlamydia in 1%. Importantly, polymicrobial infection accounted for 33% of culture positive cases. Antimicrobial treatment was changed on the basis of culture results in 17 cases (16.5%). Median initial visual and final best corrected visual acuity was 6/36-6/48 (logMAR 0.86) (IQR 0.39-2.00) and 6/12-6/15 (logMAR 0.360) (IQR 0.15-1.70), respectively. Previous ocular surgery and topical corticosteroid use were significantly associated with poorer visual acuity. The mean hospital stay was 5.8 days and the median 4.0 (IQR 2.0-8.0) days. Longer duration of stay was associated with the presence of hypopyon, larger ulcers, previous ocular surgery, and poor visual acuity. Infectious keratitis is an important cause of ocular morbidity. A significant proportion of cases have potentially modifiable risk factors. Previous ocular surgery and topical corticosteroid use, in particular, were associated with poorer visual outcomes. Many cases of severe keratitis might be avoided, or their severity reduced, by appropriate education of patients and ophthalmologists.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 12-2005
DOI: 10.1016/J.JCRS.2005.10.022
Abstract: Completion of a scientific manuscript for submission to a peer-reviewed journal is a daunting task for clinicians and scientists early in their careers. In an ongoing series, this third article is the first of 2 related articles that deal with the basics of producing a high-quality research manuscript. Although ophthalmology and vision science are the principal focus of this series, the general concepts essential to producing a quality manuscript are applicable to erse fields of research. This article highlights the exponential growth in the scientific literature over the past 40 years, considers why it is important to publish completed research, and discusses the necessity of identifying the key messages of the research, and their context, in relation to the published literature. The ethics of publishing biomedical research and scientific misconduct, such as duplicate publication or plagiarism, are outlined. To avoid later conflict, there is a critical need for coworkers to carefully address authorship order and inclusion early in the manuscript process. Internationally agreed guidelines are identified to guide this process. The importance of choosing the correct journal for a specific article and the nature of basic citation indices are discussed. The article concludes by elaborating and contrasting different scientific writing styles and emphasizing the considerable importance of developing a representative title and applying clarity and appropriate structure to the abstract.
Publisher: BMJ
Date: 2019
DOI: 10.1136/BMJPO-2018-000376
Abstract: Early detection of ocular abnormalities in newborn infants is essential for timely diagnosis and treatment. This study aimed to assess wide-field digital imaging for universal newborn eye screening (UNES) to determine the prevalence of ocular abnormalities, including retinal haemorrhages, in newborn infants in New Zealand. Prospective ocular screening study of infants. A public hospital maternity ward and a community birth centre in Auckland, New Zealand. A total of 350 infants were enrolled in UNES, those with birth weight g or gestational age weeks were excluded. Wide-field digital images of the external eye and retina were captured by RetCam (Natus Medical, San Carlos, California, USA) and reviewed by an ophthalmologist via an established telemedicine methodology. Detection of ocular abnormalities, including retinal haemorrhages. Correlation between haemorrhages and maternal, obstetric and neonatal factors. A total of 346 infants completed screening (median age 2 days). Retinal haemorrhages were present in 50 cases (14.5%), two cases exhibited persistent retinal haemorrhages at 6-week follow-up. A significant increase in the odds of retinal haemorrhages was present for vaginal delivery compared with caesarean section. Other ocular abnormalities, including congenital cataract and optic nerve hypoplasia, were present in 1.4% of infants. Ocular abnormalities were detected by UNES including congenital cataract and optic nerve hypoplasia. However, retinal haemorrhages, significantly associated with delivery modality, were the most common abnormality detected. The majority of retinal haemorrhages resolved spontaneously.
Publisher: Association for Research in Vision and Ophthalmology (ARVO)
Date: 02-07-2013
Abstract: To assess the effects of panretinal photocoagulation (PRP) for diabetic retinopathy (DR) on the human corneal subbasal nerve plexus (SBNP) and to investigate correlations between corneal subbasal nerve (SBN) density, corneal sensitivity, and diabetic peripheral neuropathy. Thirty-eight subjects with at least a 10-year history of diabetes mellitus (DM) or DR were included. Subjects were assigned to a PRP group (n = 19), having undergone a treatment of retinopathy in at least one eye or a non-PRP group (n = 19), with no history of PRP. The Michigan Neuropathy Screening Instrument (MNSI) was administered to enable quantification of neuropathic symptoms. Laser scanning in vivo confocal microscopy was performed to capture images of the corneal SBNP to allow determination of SBNP density. Central corneal sensitivity (CST) was evaluated by noncontact aesthesiometry and peripheral vibration perception threshold was measured with a biothesiometer. Mean SBNP densities were 12.27 ± 4.28 mm/mm²) in the PRP group and 12.75 ± 3.59 mm/mm² in the non-PRP group. There were no significant differences in SBNP density (P = 0.71), CST (P = 0.84), MNSI score (P = 0.19), and biothesiometry (P = 0.77) between the PRP and non-PRP groups. When data from both groups (n = 38) were combined, corneal sensitivity was modestly correlated with SBNP density (r = 0.30, P = 0.06), and peripheral biothesiometry (r = 0.26, P = 0.11). In DM correlation of corneal sensitivity, SBNP density, and peripheral biothesiometry may have a potential role in estimating the severity of peripheral neuropathy. Corneal SBNP density and sensitivity appear to be unaffected by PRP laser treatment compared with non-PRP diabetic eyes.
Publisher: Wiley
Date: 06-2003
Publisher: Informa UK Limited
Date: 07-2013
DOI: 10.1111/CXO.12030
Abstract: We describe the corneal microstructural changes in a patient with spheroidal degeneration using in vivo confocal microscopy. Multiple hypo- and hyper-reflective spherical lesions were observed in the anterior corneal stroma and Bowman’s layer ranging from 45 to 220 mm in size. The corneal epithelium, posterior stroma and endothelium were otherwise unaffected. In vivo confocal microscopy demonstrates good correlation with excised histological s les in climatic droplet keratopathy. It provides a non-invasive technique to examine the living cornea for degenerative disease and acts as a bridge between clinical and laboratory observations.
Publisher: Elsevier BV
Date: 04-2012
DOI: 10.1016/J.EXER.2012.02.009
Abstract: Rhegmatogenous retinal detachment is by far the most common indication for retinal surgery and a major cause of severe vision loss. Increased levels of glutamate found in the vitreous of human patients and persistent remodeling, even after reattachment, suggest substantial neurochemical, functional and anatomical changes have occurred in the detached retina. Therefore, this study was designed to characterize the morphological changes and glutamate receptor functionality in human rhegmatogenous retinal detachment. A cation channel permeating probe, agmatine (1-amino-4-guanidobutane AGB), was employed to track endogenous and kainate (KA) driven channel functionality combined with immunocytochemical characterization of cellular remodeling. In the detached retina increased AGB permeability was identified in the outer retina while there was a decrease in the inner retina in basal conditions. KA receptors exhibited increased AGB permeability in ON bipolar cells and decreased permeability in calbindin labeled inner retinal cells. All retinal detachment s les demonstrated ectopic synaptic protein expression, photoreceptor processes extending toward the inner retina, and other remodeling features of retinal degeneration. These anatomical changes have been demonstrated in animal studies and are novel features unreported in primary cases of human retinal detachment. We conclude that deafferentation in retinal detachment leads to alteration of the glutamatergic pathway.
Publisher: Press of International Journal of Ophthalmology (IJO Press)
Date: 12-05-2017
Publisher: Elsevier BV
Date: 12-2018
Publisher: Informa UK Limited
Date: 03-2013
DOI: 10.1111/CXO.12035
Abstract: In an era of scientific method, precision of nomenclature and an electronically accessible publication record, the early history of keratoconus still remains, in parts, as complex and perplexing as the disease itself. Historically, the disease has been somewhat confusingly referred to by several different terms, including hyperkeratosis, ochlodes, conical formed cornea, cornea conica, cornée conique, sugar loaf cornea, prolapses corneae, procidentia corneae, staphyloma transparent de la cornée, staphyloma pellucidum, staphyloma corneae totale conicum pellucidum, staphyloma diaphanum, keratconus and keratoconus. In his major 1854 treatise on conical cornea, John Nottingham is widely cited as the first author to succinctly define keratoconus and its associations however, for 150 years prior to this landmark publication, others had been slowly deciphering elements of keratoconus and distilling their knowledge in a series of publications obscured by the passage of years. Uncritical re-writing of core information and references without their full verification has also led to confusion in the published literature in the 150 years since Nottingham's comprehensive description of keratoconus. In the light of the preceding limitations in the established literature, the authors conducted an historical survey, based on the analysis of original sources, to more fully establish the chronology of early descriptions of keratoconus prior to 1854, with particular focus on the works of Duddell, Taylor, Mauchart, Scarpa, Wardrop, Lyall, MacKenzie, Lawrence, Schmidt, von Ammon and Pickford. This review attempts to place the observations of these practitioners and others both in the context of contemporary ophthalmic practice and historical precedent.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 11-2019
DOI: 10.1097/APO.0000000000000265
Abstract: The cornea is the major focusing structure of the human eye and the corneal endothelium maintains the relatively dehydrated state of the cornea required for clarity. The endothelial cells respond to disease or injury by migration and cellular enlargement. Our current understanding is that there is a very limited degree of proliferative or regenerative capacity in the human corneal endothelium. Thus, corneal endothelial diseases may result in corneal edema, significantly impact vision and quality of life. Contemporary surgical transplantation options for treating moderate to advanced endothelial dysfunction include penetrating keratoplasty (PK), Descemet stripping endothelial keratoplasty (DSEK), and Descemet membrane endothelial keratoplasty. Advances in surgical techniques aim to bring faster visual recovery and improve visual outcomes however, there is still a significant donor cornea shortage worldwide and alternative methods for treatment for corneal endothelial disease are rapidly evolving. Indeed, we are at a pivotal point in corneal transplantation for endothelial disease and novel surgical strategies include using 1 donor for multiple recipients, a minimally attached endothelial graft, and Descemet membrane stripping only. Crucially, forthcoming approaches include the use of Rho-Kinase (ROCK) inhibitors, endothelial cell therapy, tissue engineered grafts, and consideration of stem cell techniques. Ultimately, the choice of technique will be dependent on recipient factors such as age, type of endothelial disease, extent of the disease, and associated ocular disorders. The safety and efficacy of these rapidly developing treatments warrant further investigations. In time, some or all of these alternatives for corneal transplantation will alleviate the reliance on limited corneal donor tissue.
Publisher: Elsevier BV
Date: 07-2014
DOI: 10.1111/HPB.12187
Publisher: Wiley
Date: 09-1995
Publisher: Wiley
Date: 02-2003
DOI: 10.1046/J.1442-9071.2003.00610.X
Abstract: Citation analysis has evolved over the last 50 years as one parameter for assessing the quality of research published in scientific, technology and social science journals. This is based on the assumption that influential research is widely cited by other scientists and clinicians. With the advent of the Internet, Journal Citation Reports from the Institute for Scientific Information (ISI-JCR) have become widely available to in iduals and institutions. In an increasingly competitive research environ-ment, aspects of citation analysis have been suggested as simple proxy, objective measures to evaluate the research quality of a journal, published articles, research institutions and even in idual researchers. This review article provides an overview of citation analysis, including definitions, uses of these reports, and related controversies and potential abuses. As it has become the most commonly used indicator, there is a particular focus on the use of the Journal Impact Factor (JIF). This is a widely quoted measure indicating the frequency with which the average article published in a journal of interest will be quoted within a specified time frame that therefore allows approximate comparisons of journals within a particular field of interest. Given the relative paucity of information in this area, emphasis is placed on citation analysis within ophthalmology, in particular in regard to the 43 ophthal-mology, vision science and optometry journals that are listed in the ISI-JCR 2001 reports.
Publisher: Wiley
Date: 11-2017
DOI: 10.1111/CEO.13075
Publisher: Wiley
Date: 04-2019
DOI: 10.1111/CEO.13513
Abstract: Pseudophakic cystoid macular oedema (PCMO) remains a significant cause of compromised postoperative vision in contemporary cataract surgery. Well-established risk factors include intraoperative complications such as posterior capsule rupture and preoperative factors including: diabetes mellitus, uveitis, retinal vein occlusion, epiretinal membrane. The role of topical glaucoma medications in PCMO continues to be debated. Current treatment strategies largely target suppression of inflammation. Topical NSAIDs remain the mainstay in prophylaxis and treatment of PCMO. Topical corticosteroids are commonly used as monotherapy or in combination with NSAIDs. Unfortunately, high-quality trials are notably lacking for other PCMO treatment modalities such as: periocular corticosteroids, orbital floor triamcinolone, intravitreal triamcinolone, corticosteroid implants, intravitreal bevacizumab and pars-plana vitrectomy. A lack of consistency in defining PCMO and resolution of PCMO explains why even large systematic reviews may come to contradictory conclusions. This review explores the varied contemporary evidence-base in relation to the aetiology, diagnosis, prophylaxis and treatment of PCMO.
Publisher: Wiley
Date: 28-04-2020
DOI: 10.1111/CEO.13756
Publisher: Association for Research in Vision and Ophthalmology (ARVO)
Date: 07-2006
DOI: 10.1167/IOVS.05-1492
Abstract: To elucidate the structure of the human corneoscleral limbus by in vivo laser scanning confocal microscopy and to correlate limbal epithelial dimensions and density with the central epithelium and in relation to age. Fifty adult subjects were recruited into one of two age groups: younger (age or=45 years). Fifty left eyes of these 50 healthy subjects were examined by laser scanning in vivo confocal microscopy, to assess the basal epithelium of the central cornea and inferior limbus. Mean epithelial cell diameter, area, and density were calculated for the central basal epithelium, limbus-corneal basal epithelium, and limbus-palisade epithelium. Data were analyzed in relation to the two age groups, group A, 30+/-6 years (n=25 mean+/-SD), and group B, 60+/-11 years (n=25 P<0.01). Mean epithelial density in the limbus-cornea and limbus-palisade regions decreased significantly with age: limbus-cornea group A=7253+/-1077 cells/mm2 group B=6614+/-987 cells/mm2, P=0.03 limbus palisade group A=5409+/-799 cells/mm2, group B=5055+/-722 cells/mm2, P=0.03). Central corneal epithelial density did not change with age: group A=6162+/-503 cells/mm2, group B=6362+/-614 cells/mm2, P=0.08. Mean epithelial density was greatest at the limbus-cornea (7010+/-1081 cells/mm2) and lowest at the limbus-palisades (5289+/-847 cells/mm2). The mean width of palisade ridges was 25.0+/-6.3 microm. This is the first study to image clearly the living human corneal limbus by laser scanning in vivo confocal microscopy and to demonstrate quantitative changes in the basal epithelium with age.
Publisher: BMJ
Date: 07-2002
DOI: 10.1136/BJO.86.7.815
Publisher: Wiley
Date: 11-2008
DOI: 10.1111/J.1442-9071.2008.01900.X
Abstract: To ascertain the level and speed of visual recovery after penetrating keratoplasty for keratoconus. A retrospective review was performed of 100 consecutive cases of penetrating keratoplasty for keratoconus, performed between 1999 and 2005. Review assessed visual function and the speed at which patients achieved a functional best corrected visual acuity (BCVA) of > or = 6/12 either with glasses or phoropter. Analysis of visual, refractive and keratometric results were made on 76 eyes that had reached 6 months after suture removal. Intraoperative and postoperative complications including graft rejections were recorded. Post keratoplasty, 43.4%, 78.9% and 96.1% of patients achieved a BCVA of 6/12 or better by 1, 3 and 6 months, respectively. The mean time to achieve a BCVA of 6/12 was 9.6 weeks. Only 5.3% of patients required a rigid gas permeable contact lens. Overall 42.4% of patients had unaided visual acuity of 6/12 or better at 12 months. The mean refractive cylinder and standard deviation was 2.78 +/- 1.6 D, and the mean spherical equivalent was -1.12 +/- 2.9 D. There were no significant intraoperative complications, and although 3.9% of eyes had at least one graft rejection episode there were no graft failures. Penetrating keratoplasty is an effective method for treating advanced keratoconus. By 3 months almost all patients are able to achieve a BCVA of 6/12 or better with progressive improvement over time. This technique allows almost half of patients to achieve an unaided vision of 6/12 or better with sutures in situ.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 10-2005
DOI: 10.1016/J.JCRS.2005.10.031
Abstract: In an increasingly "publish or perish" clinical and academic environment, all clinicians and clinician-scientists involved in research must have a firm understanding of the measures commonly used to assess the quality of scientific journals and, by default, those extended to grade in idual articles and authors. The publication of research is a vital part of clinical and experimental research, and citation analyses of research publications have increasingly been adopted as a means of assessing the apparent quality of journals and the research published therein. In the first of a series of articles for those embarking on ophthalmic and vision science research, this paper discusses the key features of citation analysis, concentrating on the 2004 Journal Citation Report figures for the field of ophthalmology that include 42 ophthalmology, vision science, physiological optics, and optometry journals. The Institute for Scientific Information (ISI) calculates a number of parameters including citation counts, Journal Impact Factor (JIF), Immediacy Index, and cited/citing half-life. This article discusses the methods of calculation and possible uses along with current controversies and potential abuses. The JIF and its relevance, potential bias, and limitations are discussed in depth as it has become the most widely used analysis of journal quality. The possible alternatives to ISI citation analysis are presented, and we conclude that citation analysis can be considered a reasonable measure of journal research quality only if used correctly.
Publisher: Wiley
Date: 04-2019
DOI: 10.1111/CEO.13512
Abstract: In vivo confocal microscopy (IVCM) allows non-invasive imaging of the living human cornea, specifically enabling the detection of immune cells in the healthy and diseased ocular anterior segment. Studies using IVCM have provided insight into the effects of contact lens wear on corneal Langerhans cell density and morphology, and the effects of eye drops on conjunctiva-associated lymphoid tissue. IVCM has also been shown to be a useful adjunctive diagnostic tool in distinguishing infective and non-infective uveitis and in diagnosing atypical infective keratitis. In the research setting, this technology has enhanced our understanding of the role of inflammatory cells in corneal neuropathy and angiogenesis. In vivo-ex vivo correlation using animal models has helped overcome some of the difficulties in identifying cell type on IVCM images. As highlighted in this review, currently there are multiple established, and emerging, clinical and research applications for IVCM in the inflamed anterior segment.
Publisher: Elsevier BV
Date: 12-2005
DOI: 10.1016/J.CLAE.2005.10.002
Abstract: Generally in keratoconus the corneal apex displacement is inferior in position and bilateral in expression. Two young male keratoconic subjects enrolled in the Dundee University Scottish Keratoconus Study (DUSKS) demonstrated with corneal topography the presence of unilateral superior keratoconus. Successful visual rehabilitation of a superior cone with contact lens fitting represents a particular challenge to the contact lens practitioner. This report discusses the management of two such cases.
Publisher: Wiley
Date: 2007
DOI: 10.1111/J.1442-9071.2007.01423.X
Abstract: In vivo confocal imaging of the cornea has evolved exponentially over the last few decades and it has increasingly emerged from the laboratory to be used in the clinical setting in relation to inherited corneal diseases, corneal infections, contact lens wear and the effects of corneal surgery. This evolution has led to significant enhancement of our knowledge of the living cornea in both its physiological and pathological states. A number of in vivo confocal microscope devices using white, and more recently coherent, light sources have been developed to provide non-invasive assessment of the corneal microstructure at a lateral resolution of 1-2 microm. The fundamental principles of in vivo confocal microscopy and the key differences between these devices are highlighted in this review. By providing a systematic review of the extensive literature on the human cornea, this perspective paper aims to provide an overview of how in vivo confocal microscopy has contributed to our greater understanding of the human cornea in health, in disease, and following surgery, with a particular emphasis on quantitative data. The utility and limitations of available data are highlighted as are possibilities for the future development of this innovative technology.
Publisher: Mary Ann Liebert Inc
Date: 02-2016
Publisher: Wiley
Date: 08-2015
DOI: 10.1111/ANS.12341
Publisher: Elsevier BV
Date: 11-2017
DOI: 10.1016/J.SURVOPHTHAL.2017.02.002
Abstract: Stem cells are capable of giving rise to progenies with specific functional and morphological traits and, in recent years, extraordinary scientific advances have initiated an era of hope for clinical regenerative strategies and tissue engineering applications. We appraise the potential benefits of human umbilical cord-derived stem cell therapy and consider current approaches to utilize these stem cells in corneal epithelial, stromal, and endothelial disorders.
Publisher: Wiley
Date: 05-2009
Publisher: Informa UK Limited
Date: 2001
DOI: 10.1080/01421590120063349
Abstract: The introduction of an outcome-based approach to education at Dundee Medical School in Scotland instigated a search for assessment methods that would appropriately assess the students' achievements in terms of the learning outcomes. Portfolio assessment has been developed for this purpose and has been adopted for the summative assessment of students in their final examination in Dundee. The contents of the portfolio and the assessment process have been defined and the first cohort of students to be assessed in this way has been studied. The evaluation of the approach demonstrated strong staff support. Students were also positive although with some reservations. It is concluded that portfolio assessment is a powerful approach to assessing a range of curriculum outcomes not easily assessed by other methods and is worthy of inclusion in the assessor's toolkit.
Publisher: Elsevier BV
Date: 2012
DOI: 10.1016/J.EXER.2011.11.008
Abstract: Glutamate is the major neurotransmitter in the vertebrate retina. Neurons involved in the glutamate pathway express α-amino-3-hydroxyl-5-methylisoxazole-4-propionic acid (AMPA), kainic acid (KA) and N-methyl-D-aspartate (NMDA) receptors. Functional characterization of these ionotropic glutamate receptors can be achieved by using a cation channel permeating probe named agmatine (1-amino-4-guanidobutane AGB). Retinal mapping using this guanidinium analog has certain advantages including the immunocytochemical identification of a whole population of neurons expressing functional glutamate gated receptor channels. We have extended AGB studies into the functionality of ionotropic receptors in peripheral aged human retina to serve as a comparison for functional analysis of retinopathies such as retinal detachment. We probed the human retina with AGB after activation with AMPA, KA and NMDA. The results showed patterns of AGB entry into neurons consistent with those previously observed in subunit localization studies in adult mammalian retinae including primates. Application of 30 μM AMPA activated receptors in virtually all calretinin immunoreactive AII amacrine cells in the mid-peripheral human retina. About half of the AII amacrine cells showed AGB permeation after incubation with 50 μM KA. Some bipolar cells including DB3 OFF bipolar cells displayed functional KA receptors. Colocalization of AGB with parvalbumin labeled horizontal cells revealed functional KA and AMPA receptors with no responsiveness to NMDA activation. NMDA activation resulted in AGB labeling of ganglion cells and amacrine cells. The present study provides a description of functional ionotropic glutamate receptors in the aged mid-peripheral human retina.
Publisher: Elsevier BV
Date: 07-2006
DOI: 10.1016/J.CLAE.2006.03.003
Abstract: As part of a longitudinal observational prospective study (Dundee University Scottish Keratoconus Study, DUSKS) a caucasian female subject was identified with keratoconus affecting both corneas. Of interest was that the subject's mother was a monozygotic twin, however, the mother was reportedly unaffected by keratoconus, although her sister (the subject's aunt) had been diagnosed with keratoconus. Computer video-keratoscopy (CVK) was undertaken was on this family to clarify this apparent discordance. CVK demonstrated the variable expression of the keratoconic phenotype, by identifying evidence of subclinical keratoconus in the 'unaffected' twin. So far only one set of monozygotic twins with keratoconus have been reported within the UK, this paper reports a second. Since CVK has been available the majority agree on concordance of keratoconus expression but not all, including this study. If monozygotic twin studies demonstrate heterogeneity of keratoconus this may at least explain the contradictory data that exists within the literature and why the inheritance pattern of keratoconus is still unclear in 2005.
Publisher: Elsevier BV
Date: 04-2006
DOI: 10.1016/J.EXER.2005.09.006
Abstract: The purpose of this study was to determine the significance of hyper-reflective corneal endothelial nuclei imaged by in vivo confocal microscopy. A retrospective analysis was performed using a database of 505 patients that had undergone in vivo confocal microscopy of the cornea. All subjects with hyper-reflective endothelial nuclei were identified and these images were analysed to determine corneal endothelial cell density and morphology. The clinical notes of these patients were reviewed and corresponding data regarding corneal thickness was obtained from a related database of Orbscan II pachymetry. Hyper-reflective endothelial nuclei were identified in 41 eyes of 39 (7.7%) patients. Diagnoses included previous cataract surgery or penetrating keratoplasty, posterior polymorphous dystrophy, Fuchs' endothelial dystrophy and irido-corneal endothelial syndrome. No patients with clinically normal corneas exhibited bright endothelial nuclei. The mean endothelial cell density in this group was 1325+/-872 cells mm(-2) and endothelial density was below age-adjusted normal values in 69.2% of patients. Both cellular polymegathism (coefficient of variation of cell area 33.9+/-7.4%) and cellular pleomorphism were noted (51.8+/-9.0% hexagonal cells). The mean central corneal thickness was 582+/-52 microm. There was no significant difference in endothelial density and morphology compared to cases that had low endothelial density but did not exhibit bright nuclei. In conclusion, this study is the first to investigate the significance of bright endothelial nuclei detected by in vivo confocal microscopy. The strong association with corneal disease states suggests that the most likely explanation for this appearance is the alteration in cellular/nuclear morphology, composition or function.
Publisher: Elsevier BV
Date: 09-2017
DOI: 10.1016/J.AJO.2017.06.014
Abstract: To assess the effect of preoperative risk stratification for phacoemulsification surgery on intraoperative complications in a teaching hospital. Prospective cohort study. Prospective assessment of consecutive phacoemulsification cases (N = 500) enabled calculation of a risk score (M-score of 0-8) using a risk stratification system. M-scores of >3 were allocated to senior surgeons. All surgeries were performed in a public teaching hospital setting, Auckland, New Zealand, in early 2016. Postoperatively, data were reviewed for complications and corrected distance visual acuity (CDVA). Results were compared to a prospective study (N = 500, phase 1) performed prior to formal introduction of risk stratification. Intraoperative complications increased with increasing M-scores (P = .044). Median M-score for complicated cases was higher (P = .022). Odds ratio (OR) for a complication increased 1.269 per unit increase in M-score (95% confidence interval [CI] 1.007-1.599, P = .043). Overall rate of any intraoperative complication was 5.0%. Intraoperative complication rates decreased from 8.4% to 5.0% (OR = 0.576, P = .043) comparing phase 1 and phase 2 (formal introduction of risk stratification). The severity of complications also reduced. A significant decrease in complications for M = 0 (ie, minimal risk cases) was also identified comparing the current study (3.1%) to phase 1 (7.2%), P = .034. There was no change in postoperative complication risks (OR 0.812, P = .434) or in mean postoperative CDVA (20/30, P = .484) comparing current with phase 1 outcomes. A simple preoperative risk stratification system, based on standard patient information gathered at preoperative consultation, appears to reduce intraoperative complications and support safer surgical training by appropriate allocation of higher-risk cases.
Publisher: Informa UK Limited
Date: 03-2013
DOI: 10.1111/CXO.12025
Abstract: Severe loss of vision manifests from the corneal protrusion, thinning and distortion that characterises keratoconus, which in its most severe form is still treated primarily by lamellar or penetrating keratoplasty. Unfortunately, alternative therapeutic options targeting the underlying pathobiology remain limited, attributable to an incomplete understanding of the biological mechanisms instigating stromal deterioration and other disease processes. We postulate that underlying abnormalities in stromal repair and reactive species-linked activities and the interaction between these phenomena are implicated in the development of keratoconus. This revised interpretation of the pathophysiology may, with further investigation, advance our knowledge and the clinical management of this prevalent ectatic disorder.
Publisher: Elsevier BV
Date: 10-2020
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 2005
DOI: 10.1016/J.JCRS.2004.09.047
Abstract: An extensive electronic search was undertaken in January 2004 to identify all relevant peer-reviewed publications on Orbscan slit-scanning/Placido computerized topography. Ninety-one publications were identified. These address elevation topography and best-fit sphere, accuracy and repeatability of anterior and posterior corneal elevation and keratometric maps, comparison of Orbscan-acquired data and Placido-based computerized videokeratography instruments, pachymetry measurement and correlation with ultrasound, screening eye-bank corneas, detection of keratoconus, identifying corneal ectasia after refractive surgery, and miscellaneous applications. Studies were analyzed and critically compared in relation to attributes, applications, and limitations of Orbscan corneal topography. The review highlights advantages of this technique in assessing the cornea in health and disease and after surgery and identifies specific aspects that require further investigation and clarification.
Publisher: Elsevier BV
Date: 05-2023
Publisher: No publisher found
Date: 2003
Publisher: Springer International Publishing
Date: 2015
Publisher: Informa UK Limited
Date: 09-2015
DOI: 10.1111/CXO.12260
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 12-2021
Publisher: Wiley
Date: 19-05-2020
DOI: 10.1111/CEO.13766
Publisher: BMJ
Date: 05-12-2009
Abstract: The purpose of this study was to use laser scanning in vivo confocal microscopy to elucidate the location and morphology of stromal nerves in the normal human central cornea. Analysis was performed via an established database of laser-scanning in vivo confocal microscopy on images of the central cornea of normal subjects. The depth and morphology of the stromal nerves were determined. The population of this study consisted of 99 eyes of 99 healthy subjects (38 male, 61 female). The mean age of the group was 34.7 (SD 13.3, range 13-84) years. Two morphologically different populations of stromal nerves were observed: (1) straight, dichotomous branching nerves and (2) tortuous nerves with a beaded appearance. The mean recorded depth of straight stromal nerves (186 (SD 66) mum) was significantly deeper than the mean depth of the tortuous stromal nerves (140 (SD 87) mum) (p<0.001). The current study identified two morphologically distinct stromal nerve populations in the normal human cornea. We hypothesise that the two morphological nerve populations described here may represent functionally heterogeneous nerves. Further research is required to determine if these in fact represent different types of sensory nerves.
Publisher: BMJ
Date: 02-2001
DOI: 10.1136/BJO.85.2.249
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 04-2008
Publisher: Wiley
Date: 10-10-2019
DOI: 10.1111/CEO.13646
Publisher: Wiley
Date: 2021
DOI: 10.1111/CEO.13888
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 02-2008
DOI: 10.1016/J.JCRS.2007.09.025
Abstract: We report an unusual case of presumed late-onset unilateral diffuse lamellar keratitis of uncertain etiology in a 23-year-old man who presented with elevated intraocular pressure following uneventful laser in situ keratomileusis (LASIK). After treatment with topical corticosteroid therapy, the condition progressed to interface fluid syndrome. Isolated pockets of fluid were clearly demonstrated at the level of the LASIK flap interface on slitl biomicroscopy and in Pentacam Scheimpflug images.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 10-2011
DOI: 10.1016/J.JCRS.2011.04.030
Abstract: To examine whether clinically significant differences exist in corneal elevation data from a s ling of countries worldwide. International multicenter. Evaluation of diagnostic test or technology. One randomly selected eye of normal adults from 8 countries spanning 6 continents was examined using the Pentacam Eye Scanner. Anterior and posterior elevations were measured at the apex and thinnest point. Differences between countries were assessed by Kruskal-Wallis. Normative thresholds were defined according to the Tukey method. The study examined 1 eye of 555 patients. Median elevations were similar across countries. Upper limits of normal for collective international data were 3.5 μm, 6.0 μm, 7.5 μm, and 13.5 μm at the anterior apex, anterior thinnest point, posterior apex, and posterior thinnest point, respectively. These and country-specific thresholds were similar to normal values from previous data however, country-specific thresholds flagged additional eyes in China, Egypt, and India. Those thresholds were 4.5 μm at the anterior thinnest point (China and Egypt), 7.4 μm at the posterior apex (India), and 11.0 μm and 12.0 μm at the posterior thinnest point (China and Egypt, respectively). In general, international variations were clinically insignificant thus, current screening guidelines maintained their applicability. Notable exceptions were China, Egypt, and India, where country-specific thresholds may better reflect the test populations and minimize potential false negative results from screening. No author has a financial or proprietary interest in any material or method mentioned. Additional disclosures are found in the footnotes.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 02-2015
Publisher: Wiley
Date: 04-2006
DOI: 10.1111/J.1442-9071.2006.01202.X
Abstract: A 54-year-old man with a history of severe proliferative diabetic retinopathy in both eyes and profound visual impairment presented with severe corneal blood staining in the left eye secondary to a "spontaneous" total hyphaema and raised intraocular pressure in an eye with iris neovascularization. Despite anterior chamber washout, the cornea remained virtually opaque and thickened. The subject subsequently underwent pars plana vitrectomy with endolaser using a temporary keratoprosthesis, insertion of a Morcher iris-surround intraocular lens and penetrating keratoplasty. Histopathology of the excised corneal button revealed fine eosinophilic granules composed of aggregations of haemoglobin and its breakdown products dispersed throughout the stroma, with occasional foci of weakly positive Perl staining for intracellular haemosiderin. Fluorescence confocal microscopy revealed a marked increase in fluorescence throughout the corneal stroma and the basal epithelial layer. This case highlights the microstructural features and aspects of the surgical management of severe corneal blood staining.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 08-2017
Publisher: BMJ
Date: 12-1995
Publisher: Wiley
Date: 04-2009
Publisher: Informa UK Limited
Date: 07-2014
DOI: 10.1111/CXO.12138
Abstract: Keratoconus manifests as a conical protrusion of the cornea and is characterised by stromal thinning. This causes debilitating visual impairment which may necessitate corneal transplantation. Therapeutic targets related to disease mechanisms are currently lacking, as the pathobiology remains unclear. Many pathological features may be manifestations of defects in wound healing and reactive oxygen species (ROS)-associated functions. In a wide range of tissue and cell types, antioxidant exposure has beneficial effects on both of these pathways. This study investigated the effect of treatment with the antioxidant riboflavin on wound healing and ROS-associated functions in keratoconus. Stromal cells were isolated from human central keratoconic (n = 3) and normal (n = 3) corneas. Total RNA was extracted and reverse-transcribed into complementary DNA. The gene expression of 22 genes involved in repair (eight normal and four repair-type extracellular matrix constituents) and ROS-associated processes (eight antioxidants and two ROS-synthesising oxidases) was quantified using quantitative polymerase chain reaction. This was also performed on keratoconic stromal cells treated in vitro with riboflavin (n = 3). In stromal cells from untreated keratoconic corneas (compared with untreated normal corneas), there was an up-regulation of 7/12 extracellular matrix elements. Four of eight antioxidants and two of two oxidases were also increased. In treated keratoconic corneas (compared with untreated keratoconic corneas), six out of eight normal extracellular matrix constituents were up-regulated and two of four repair-type molecules were reduced. An increase was also observed in seven out of eight antioxidants and there was a diminution in two out of two oxidases. Riboflavin encourages the synthesis of a normal extracellular matrix and reduces reactive oxygen species levels in keratoconus. This supports the occurrence of wound healing and ROS-associated abnormalities in keratoconus. By targeting the causative disease mechanisms, riboflavin may have therapeutic potential in the clinical management of keratoconus.
Publisher: Wiley
Date: 23-10-2015
DOI: 10.1111/CEO.12439
Publisher: Association for Research in Vision and Ophthalmology (ARVO)
Date: 24-03-2020
DOI: 10.1167/TVST.9.4.24
Publisher: Wiley
Date: 16-11-2018
DOI: 10.1111/CEO.13092
Publisher: Wiley
Date: 16-11-2018
DOI: 10.1111/CEO.13093
Publisher: Medknow
Date: 2021
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 08-2002
DOI: 10.1016/S0886-3350(02)01236-1
Abstract: This case reports an association between 2 uncommon flap complications in 1 eye related to epithelial toxicity and subsequent epithelial defect secondary to prolonged intraoperative exposure to topical anesthesia. A patient had hyperopic laser in situ keratomileusis (LASIK) for the correction of +2.75 +1.75 x 70 in the left eye. Because of the patient's anxiety and movement, additional topical local anesthesia was used and the flap remained reflected for 5 minutes. Immediately postsurgery, a toxic appearance was noted in the epithelium of the LASIK flap 24 hours later, a large central epithelial defect was identified. Three days post- LASIK, the epithelial defect had healed but diffuse lamellar keratitis was noted in the interface, particularly underlying the location of the original epithelial defect. Over 6 weeks, a self-limiting epithelial ingrowth developed in the inferior interface. Fourteen months post-LASIK, the uncorrected visual acuity was 6/9 with a residual refraction of +0.50 +0.50 x 90.
Publisher: Wiley
Date: 05-2008
Publisher: Wiley
Date: 12-2009
DOI: 10.1111/J.1442-9071.2009.02190.X
Abstract: The majority of ophthalmology and visual science journals reject more original manuscripts than they accept. Submissions to Clinical and Experimental Ophthalmology were analysed over a 12-month period with the aim of identifying common reasons for editorial rejection of manuscripts. A content analysis was carried out of reviewer and section editor comments of all rejected manuscripts (original papers) submitted to Clinical 0mp Experimental Ophthalmology between 1 January 2008 and 31 December 2008. Comments were categorized by reasons for rejection. A total of 662 manuscripts were submitted to Clinical and Experimental Ophthalmology via ScholarOne Manuscripts from 1 January 2008 to 31 December 2008 with a final decision date of up to 1 April 2009. The overall rejection rate for these manuscripts was 73.6%. The most common reason for rejection of manuscripts was 'does not add to current literature', followed by 'poor methodology', 'problematic control groups', 'poor English and grammar oorly organized', 'needs further work/clarification' and 'simultaneous submission to another journal lagiarized' the remainder had either no readily categorized reason stated or were grouped into an 'other' category. Understanding why original research work is rejected can be invaluable to an author's publishing career. The categories that emerged from this content analysis are reflected in other literature on the topic, therefore the flaws in manuscripts rejected by Clinical and Experimental Ophthalmology appear to be both common and avoidable. Armed with this knowledge an author may strive towards a more 'rejection-proof' manuscript when submitting to ophthalmology and visual science journals.
Publisher: Wiley
Date: 20-10-2020
DOI: 10.1111/CEO.13655
Publisher: BMJ
Date: 13-05-2014
DOI: 10.1136/BJOPHTHALMOL-2013-304605
Abstract: To identify the clinical features of optic nerve hypoplasia (ONH) and prevalence within a population of New Zealand children with severe visual impairment. Retrospective review of medical records of children with severe visual impairment registered with Blind and Low Vision Educational Network New Zealand. Of 1500 children with severe visual impairment, 94 (6.3%) exhibited ONH, and 91 (97%) cases were bilateral. Of these 94 cases, 52 (55%) were males and ethnicities were European Caucasian (52%), Maori (40%), Pasifika (6%) and other (2%). Most children with ONH had poor vision, with 60% having ≤ 6/60 Snellen visual acuity equivalent. The median maternal age was 20.0 years old with 52% ≤ 20 years. There was a statistically significant over-representation of Maori ethnicity (40%) and young maternal age with age less than 20 years old (44%) in our cohort compared to the general population (14.6% and 7.4%, respectively p<0.0001). Half had hypopituitarism, while neuroimaging abnormalities were detected in 60% cases. Cerebral neuroradiographic abnormalities were found to be associated with higher rate of developmental delay (OR 9.764 95% CI 3.246 to 29.373). This is the first major study of visual impairment in New Zealand children, and it demonstrates that ONH is an important cause of severe visual disability with an over-representation of Maori children and younger maternal age.
Publisher: Association for Research in Vision and Ophthalmology (ARVO)
Date: 02-2007
DOI: 10.1167/IOVS.06-0538
Abstract: Although penetrating keratoplasty is generally considered a successful procedure, transplanted corneal tissue may exhibit abnormal epithelium, decreased sensation, and declining endothelial cell counts after surgery. This study aimed to use in vivo confocal microscopy to correlate corneal microstructure and recovery of the subbasal nerve plexus of the transplanted cornea with indications for, and time from, surgery. This was a cross-sectional study comparing corneas from 42 patients after penetrating keratoplasty with those of 30 controls. Subjects were assessed by ophthalmic history and clinical examination, computerized corneal topography, and laser scanning in vivo confocal microscopy. Time from surgery ranged from 1 month to 40 years (mean, 85 +/- 105 months). Significant reductions in epithelial (P < 0.001), keratocyte (P < 0.001), and endothelial (P < 0.001) cell densities were noted in comparison with control corneas. Significant reductions in subbasal nerve fiber density (P < 0.001) and nerve branching (P < 0.001) were also noted. Endothelial cell density decreased with time after surgery (r = -0.472 P = 0.003), and nerve fiber density (r = .328 P = 0.034) increased. Keratoconus as an indication for transplantation was associated with higher subbasal nerve fiber densities (P = 0.003) than other indications for corneal transplantation. Neither nerve fiber nor cell density was correlated with best-corrected visual acuity. Laser scanning in vivo confocal microscopy highlights profound reductions in cell density at every level of the transplanted cornea and alterations to the subbasal plexus that are still apparent up to 40 years after penetrating keratoplasty.
Publisher: Elsevier BV
Date: 1990
DOI: 10.1016/0731-7085(90)80139-G
Abstract: GC-NICIMS has been employed in the analysis of biogenic amines and their metabolites in human urine and human, bovine and porcine aqueous and vitreous humour. Several new chemical derivatization procedures have been developed in order to analyse these compounds. Concentrations of octopamines and synephrines were determined in urine from treated and untreated hypertensive subjects and normotensive in iduals there were no significant differences in concentrations of these metabolites between these groups. Human urine contained several dihydroxy-phenylethylamines which have not been reported as natural metabolites before and also 5- and 6-hydroxydopamine in relatively large amounts. Aqueous and vitreous humour contained very low quantities of noradrenaline, tyramine and dopamine but measurements were inconsistent because sometimes the levels were below the limits of detection. Metabolites of a number of biogenic amines were readily detected in aqueous and vitreous humour.
Publisher: Wiley
Date: 24-05-2002
DOI: 10.1046/J.1442-9071.2002.00507.X
Abstract: The purpose of the study was to perform quantitative analysis of the sub-basal epithelial nerve plexus of healthy, living human cornea,using real time in vivo confocal microscopy and the analySIS software system. The study was based on in vivo confocalmicrostructural analysis of 50 eyes of 50 subjects, ided into two age groups: group 1 (n = 25)25 +/- 5 years of age, and group 2 (n = 25) 70 +/- 5 years of age. All subjects exhibited clinically healthy corneas. The overall nerve density was 632.35 +/- 287.57 microm/mm2 for group 1 and 582.39 +/- 327.13 microm/mm2 for group 2. The mean fibre dia-meter was measured at 0.52 +/- 0.23 microm for group 1 and at 0.56 +/- 0.27 microm for group 2. Beadings of the nerve fibres were recorded at a density of 213 +/- 123/mm for group 1 and 201 +/- 192/mm for group 2. Establishing standards for normal nerve density and morphology of the living human cornea at different ages may be beneficial, both in early detection and follow up of various corneal diseases and in post-surgical management following corneal surgery.
Publisher: Wiley
Date: 12-2004
DOI: 10.1111/J.1442-9071.2004.00934.X
Abstract: To assess New Zealand's research productivity in the area of ophthalmology and vision science over the decade 1993-2002. New Zealand-based researchers involved in ophthalmology or vision science research, including ophthalmologists, optometrists and vision scientists were identified via professional colleges, universities and electronic databases. Peer-reviewed publications by these authors were identified by both searching electronic databases (MEDLINE/Pubmed) and personal communication with in idual researchers. Eighty-five New Zealand-based researchers involved in ophthalmology or vision science research published 446 articles in 84 scientific journals during the 10-year period. The cohort consisted of 59 ophthalmologists and 26 other researchers based in a erse range of ophthalmology, optometry and university departments. Significant collaboration was observed between groups within New Zealand and with international institutions. Comparing ophthalmologists and 'other' researchers, ophthalmologists produced 69% of all ophthalmology and vision science research publications and those classified as 'active ophthalmologist researchers' published an average of 11 (range 5-55) papers each during this decade, compared to eight (range 5-25) for the group 'other active researchers'. This was also reflected in the high productivity rate by ophthalmologists of 277 publications per 1000. Publications were identified in a wide range of journals with the majority in top 20-ranked ophthalmology journals. The trend over the decade highlighted an increase in number of scientific publications, from 43 per annum in 1993, to 68 per annum in 2002. Despite a relatively small and geographically isolated population, New Zealand ophthalmology and vision science research is highly active and collaborative, with significantly increased research productivity during the period 1993-2002. The present study is the first to document these trends and provides strong evidence to justify continued support for ophthalmology and vision science research in New Zealand.
Publisher: Elsevier BV
Date: 09-2016
DOI: 10.1016/J.AJO.2016.07.001
Abstract: To evaluate the long-term risk of endothelial rejection, graft survival, and associated factors following penetrating keratoplasty (PK) for keratoconus, with and without prior resolved corneal hydrops. Retrospective cohort study. Primary outcome measures were endothelial rejection-free survival and failure-free survival. Secondary outcome measures were corneal neovascularization following hydrops and complications following PK. A total of 245 eyes underwent PK for keratoconus with mean follow-up of 5.6 ± 3.6 years. Eyes with prior hydrops (n = 74) had lower endothelial rejection-free survival rates compared with eyes without prior hydrops: 86.5% ± 4.0% vs 86.5% ± 2.6% at 1 year, 61.0% ± 6.2% vs 76.9% ± 3.3% at 5 years, and 45.8% ± 10.1% vs 70.9% ± 4.3% at 10 years, respectively (P = .023). Multivariate analysis identified factors associated with endothelial rejection as age ≤25 years (P = .017), corneal neovascularization (P = .001), donor trephination size >8 mm (P = .017), and poor clinic attendance (P = .015). There was no difference in the failure-free survival rates with and without prior hydrops: 98.6% ± 1.3% vs 97.1% ± 1.3% at 1 year, 97.3% ± 1.9% vs 95.1% ± 1.9% at 5 years, and 97.3% ± 1.9% vs 92.2% ± 2.7% at 10 years, respectively (P = .42). Corneal neovascularization was present at the time of PK in 44.6% of eyes with prior hydrops and 7.6% without prior hydrops (P < .001). Corneal neovascularization, a frequent complication of corneal hydrops, was associated with increased risk of endothelial rejection following PK. However, allograft survival was similar in eyes with and without prior hydrops.
Publisher: Wiley
Date: 2008
DOI: 10.1111/J.1442-9071.2008.01674.X
Abstract: To identify the most published authors on the topics of 'cataract' and 'LASIK', the journals in which they publish, and the citation patterns of the most-cited articles by these authors over a 5-year publication period. Science Citation Index Expanded (SCI) was used to identify the 30 most-published authors in 'cataract' and 'laser in situ keratomileusis' (LASIK) (2000-2004 inclusive). SCI was subsequently used to analyse the recorded articles for each author in terms of source journal, the most commonly cited articles and citation source. Of the 30 most-published authors in the fields of cataract and LASIK, the USA was the most well-represented source country, accounting for 33% 20% were from Australia, and 17% from Austria. Germany and Japan each contributed 7%. Eighty per cent of the publications produced by these 30 authors (2000-2004) were in 10 journals, of which the Journal of Cataract and Refractive Surgery (JCRS) published more than one-third. Of the three most-cited articles for each author, the greatest number were published in JCRS (35.6%). The citation count of the articles had a weak correlation to the journal impact factor of the source journal however, the self-citation rate of these articles did not. The USA and Australia together were the source of more than half of the most-published authors on cataract and LASIK and the majority of articles published by the 30 most prolific authors were published in only 10 journals. The impact factors of the publication journals preferred by these authors are influenced by the article citation counts, not vice versa.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 05-2007
Publisher: Springer Science and Business Media LLC
Date: 19-01-2007
Abstract: To investigate and correlate the corneal, refractive, topographic and familial characteristics of a large cohort with keratoconus. Prospective observational study of 200 consecutive patients presenting with keratoconus during the 4 year-period 1997-2000. Subjects were examined at enrolment and at a final review. Data were collected on demographic characteristics, referral route, symptoms, refractive correction, eye rubbing, family history, medical history, slit-l biomicroscopic corneal signs, and computerized corneal topography. Mean age at enrolment was 30.9+/-10.4 (range, 12.2-72) years (N=200, 62.5% male, 93% white Caucasian) with a 5% family history of keratoconus. Atopic diseases included asthma (23%), eczema (14%), and hay fever (30%). Only 9% wore contact lenses before referral. Mean follow-up was 1004 days +/-282 (range, 390-1335) and 9.7+/-8.9 (range, 1.1-60) years from diagnosis. The mean simulated K1 corneal power at enrolment was 51.74+/-5.36 (range, 42.59-67.32) D and 88.5% exhibited bilateral keratoconus. Fifty-three (15%) topographically confirmed cones exhibited no clinical corneal signs at presentation. At enrollment, 56% had a pachymetry <0.480 mm increasing to 77% at final review. Forty-eight percent of subjects reported significant eye rubbing and there was a highly statistically significant difference (two s le t-test P=0.018) between keratoconus and control groups. TMS-2 axial corneal power was strongly associated with corneal scarring and age at diagnosis. The size of the scarring effect was 2.2 D (95% confidence interval (CI) 1.34, 3.06). This study provides an overview of a large population with keratoconus highlighting presenting features and clinical and topographic progression over a 4 year-period.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 08-12-2018
Publisher: Elsevier BV
Date: 05-2017
DOI: 10.1016/J.JOCN.2017.02.033
Abstract: Ocular surface changes and blink abnormalities are well-established in Parkinson's disease. Blink rate may be influenced by corneal sub-basal nerve density, however, this relationship has not yet been investigated in Parkinson's disease. This case-control study examined the ocular surface in patients with moderately severe Parkinson's disease, including confocal microscopy of the cornea. Fifteen patients with moderately severe Parkinson's disease (modified Hoehn and Yahr grade 3 or 4) and fifteen control participants were recruited. Ophthalmic assessment included slit-l examination, blink rate assessment, central corneal aesthesiometry and in vivo corneal confocal microscopy. The effect of disease laterality was also investigated. Of the 15 patients with Parkinson's disease, ten were male and the mean age was 65.5±8.6years. The corneal sub-basal nerve plexus density was markedly reduced in patients with Parkinson's disease (7.56±2.4mm/mm
Publisher: Wiley
Date: 2006
Publisher: Wiley
Date: 08-2010
Publisher: Asia Pacific Academy of Ophthalmology
Date: 2015
Publisher: Elsevier BV
Date: 03-2021
Publisher: Springer Science and Business Media LLC
Date: 07-2012
DOI: 10.1007/S00232-012-9460-4
Abstract: Transiently blocking the expression of the gap junction protein connexin43 using antisense oligodeoxynucleotides or blocking hemichannels with connexin mimetic peptides has been shown to significantly improve outcomes in a range of acute wound models. Less is known about their likely effects in nonhealing wounds. In the eye, prolonged inflammation and lack of epithelial recovery in nonhealing corneal epithelial wounds may lead to corneal opacity, blindness or enucleation. We report here the first human applications of antisense oligodeoxynucleotides that transiently block translation of connexin43 in a prospective study of five eyes with severe ocular surface burns (persistent epithelial defects), which were unresponsive to established therapy for 7 days to 8 weeks prior to treatment. Connexin43-specific antisense oligodeoxynucleotide was delivered in cold, thermoreversible Poloxamer407 gel under either an amniotic membrane graft or a bandage contact lens. The connexin43-specific antisense application reduced inflammation within 1-2 days, and in all five eyes complete and stable corneal reepithelialization was obtained. Recovery of the vascular bed and limbal reperfusion appeared to precede corneal epithelial recovery. We conclude that connexin modulation provides a number of benefits for nonhealing ocular burn wounds, one of which is to promote vascular recovery.
Publisher: Wiley
Date: 10-05-2018
DOI: 10.1111/CEO.13305
Abstract: To determine if endophthalmitis following cataract surgery is linked to increased mortality. Increased mortality has been linked to patients with cataract and cataract surgery. We tested the hypothesis that post-cataract endophthalmitis has a greater risk of death than pseudophakes who do not develop this complication. Case-control study conducted in a tertiary public hospital. The study group comprised 50 consecutive patients with post-cataract endophthalmitis, and these were matched with selected controls. Patients with endophthalmitis following cataract surgery were identified from a prospective electronic surgical database. Subsequently, it was determined if the patient was deceased at the time of sequestration (September 2015), and the date of death was recorded. A previously described population who had undergone cataract surgery in the same facility was selected as a control group, and the population was case-matched in terms age, gender, presence or absence of diabetes and/or hypertension. The median survival rates were determined for the control group and the patients with post-cataract endophthalmitis. Fifty patients were identified as undergoing endophthalmitis post-cataract surgery, and 48 (n = 48) met inclusion criteria (mean age 72 years ±12 SD with 30:18 F:M) 17% were diabetic, and 50% had systemic hypertension. No statistically significant difference in median survival between the study and control cases was identified (100 months (95% confidence interval 86-114) vs. 106 months (95% confidence interval 66-146), respectively, P = 0.756). Post-cataract endophthalmitis was not associated with an increased rate of mortality in this study.
Publisher: Wiley
Date: 02-06-2020
DOI: 10.1111/CEO.13784
Publisher: Association for Research in Vision and Ophthalmology (ARVO)
Date: 12-2005
DOI: 10.1167/IOVS.05-0794
Abstract: To produce a two-dimensional reconstruction map of the living human sub-basal corneal nerve plexus using in vivo confocal microscopy. Laser scanning in vivo confocal microscopy was performed on three normal eyes of three healthy human subjects. Subjects were asked to fixate on targets arranged in a grid to enable examination of the cornea in a wide range of positions. Using the section mode, a mean of 573 +/- 176 images of the sub-basal plexus were obtained for each subject. The data were arranged and images were mapped for each subject into confluent montages. Mean dimensions of the corneal areas mapped were 4.95 +/- 0.53 mm horizontally and 5.14 +/- 0.53 mm vertically. In all subjects, the sub-basal nerve plexus appeared to radiate toward a whorl-like complex centered 1 to 2 mm inferior to the corneal apex. Outside this area, the nerve fiber bundles in the remainder of the cornea were arranged in a radiating pattern. Mean nerve density was significantly higher in the inferocentral whorl region (25,249 +/- 616 microm/mm2) compared with the central cornea (21,668 +/- 1411 microm/mm2) (Mann-Whitney U test P = 0.05). This is the first study to elucidate the overall distribution of sub-basal nerves in the healthy, live central to mid-peripheral human cornea by laser scanning in vivo confocal microscopy. The whorl pattern of the sub-basal nerves is similar to that seen in the epithelium in corneal verticillata and may lend support to the theory that epithelial cells and nerves migrate centripetally in tandem.
Publisher: BMJ
Date: 07-2021
DOI: 10.1136/BMJOPHTH-2021-000824
Abstract: To evaluate the accuracy of convolutional neural networks technique (CNN) in detecting keratoconus using colour-coded corneal maps obtained by a Scheimpflug camera. Multicentre retrospective study. We included the images of keratoconic and healthy volunteers’ eyes provided by three centres: Royal Liverpool University Hospital (Liverpool, UK), Sedaghat Eye Clinic (Mashhad, Iran) and The New Zealand National Eye Center (New Zealand). Corneal tomography scans were used to train and test CNN models, which included healthy controls. Keratoconic scans were classified according to the Amsler-Krumeich classification. Keratoconic scans from Iran were used as an independent testing set. Four maps were considered for each scan: axial map, anterior and posterior elevation map, and pachymetry map. A CNN model detected keratoconus versus health eyes with an accuracy of 0.9785 on the testing set, considering all four maps concatenated. Considering each map independently, the accuracy was 0.9283 for axial map, 0.9642 for thickness map, 0.9642 for the front elevation map and 0.9749 for the back elevation map. The accuracy of models in recognising between healthy controls and stage 1 was 0.90, between stages 1 and 2 was 0.9032, and between stages 2 and 3 was 0.8537 using the concatenated map. CNN provides excellent detection performance for keratoconus and accurately grades different severities of disease using the colour-coded maps obtained by the Scheimpflug camera. CNN has the potential to be further developed, validated and adopted for screening and management of keratoconus.
Publisher: Informa UK Limited
Date: 1987
DOI: 10.3109/02688698709035311
Abstract: In a 5-year period during which 7,178 patients with head injury were admitted to a regional head injury unit, 191 motorcyclists (2.7%) were admitted with head injuries of which 76% were classified as minor, 6% as moderate and 18% as severe (in coma). Two thirds of the patients were aged 20 years or less. Eighty-two riders (43%) had some form of facial or scalp trauma and 37 (19%) sustained skull fracture. Intracranial haematomas requiring surgical evacuation were detected in 3 of the minor head injuries (2%), 2 of the moderate injuries (17%) and 11 of the severely head injured patients (32%). Twenty-nine of the 34 severely injured patients were managed using artificial ventilation and intracranial pressure monitoring. The remaining patients died before these measures could be instituted. Overall mortality was 7%, but deaths were restricted to the severely head injured, among whom there were 13 fatalities. Head injuries associated with motorcycle riding include an unduly high proportion of severe cases and occur in a young population, often within a short time of starting to ride a motorcycle. Protective headgear was virtually always worn (94%) to reduce morbidity further, increased training and supervision during the first 6 months of motorcycle ownership should be emphasized.
Publisher: Wiley
Date: 14-04-2022
DOI: 10.1002/JMOR.21476
Abstract: The illustration is an important tool to aid in the description and understanding of anatomy, and penguins (Aves: Sphenisciformes: Spheniscidae) are an important clade in environmental monitoring, paleontology, and other research fields. Traditionally, anatomic illustration has been informed by dissection. More recently, micro‐computed tomography (micro‐CT) has proven to be a powerful tool for three‐dimensional anatomic imaging, although larger specimens are more challenging to image due to increased X‐ray attenuation. Here, we used traditional dissection and micro‐CT to illustrate the skulls of Aptenodytes patagonicus , Eudyptula minor , and Pygoscelis papua , and the extracranial soft tissue of E. minor . Micro‐CT prevented the loss of orientation, disarticulation, and distortion of bones that might result from cleaning and drying skulls, while immobilization was achieved by freezing the specimens before imaging. All bony elements in the head were accurately depicted. Fixing, dehydrating, and diffusion staining with iodine (diceCT) enabled the identification of muscles and other large nonmineralized structures, but specimen preparation precluded the ability to show smaller nerves and vessels. The results presented here provide a guide for anatomic studies of penguins and our summary of s le preparation and imaging techniques are applicable for studies of other similarly sized biological specimens.
Publisher: Springer Science and Business Media LLC
Date: 14-03-2008
DOI: 10.1038/EYE.2008.52
Abstract: The purpose of this study was to quantitatively analyse laser scanning in vivo confocal microscopy images of the corneal epithelium and sub-basal nerve plexus in patients with keratoconus and to correlate these microstructural observations with corneal sensitivity. A total of 31 eyes of 31 normal human subjects, and 27 eyes of 27 subjects with an established diagnosis of keratoconus were recruited. Twelve subjects with keratoconus had never worn contact lenses (K-NCL). Fifteen subjects with keratoconus wore contact lenses routinely (K-CL). All eyes were examined using slit-l biomicroscopy, Orbscan topography, non-contact corneal aesthesiometry, and laser scanning in vivo confocal microscopy. Central corneal sensation was significantly lower in K-CL compared to normal (P=0.028). However, there was no significant difference in corneal sensation between the normal and K-NCL groups (P=0.059). Both sub-basal nerve density (P<0.001) and basal epithelial density (P<0.001) were significantly lower than normal in all keratoconic subjects. Central corneal sensation was only significantly correlated with sub-basal nerve density (P=0.001) and was not significantly correlated with any of the basal epithelial parameters. Sub-basal nerve density showed significant positive correlation with basal epithelial density (P<0.001). This quantitative study reveals decreased corneal innervation, sensation, and basal epithelial density in keratoconus. The results of this study provide strong evidence that both the sub-basal nerves and the basal epithelium may be involved in the pathogenesis of keratoconus, although it is uncertain whether these are primary or secondary changes.
Publisher: Wiley
Date: 02-05-2021
DOI: 10.1002/JMOR.21354
Abstract: Scleral ossicles and other bony elements are present in the eyes of many vertebrates, including birds. In this study, the skeletal elements present in the penguin eye and orbit were imaged using macro photographs and micro‐computed tomography (micro‐CT), to help elucidate their function and significance. A total of 36 scleral rings and three whole skulls were imaged. King ( Aptenodytes patagonicus ), Fiordland crested ( Eudyptes pachyrhynchus ), Snares crested ( Eudyptes robustus ), royal ( Eudyptes schlegeli ) and yellow‐eyed ( Megadyptes antipodes ) penguins had between 12 and 14 elements in their scleral ring while the gentoo ( Pygoscelis papua ) had 14 and 17 little penguins ( Eudyptula sp.) consistently had between 10 and 12 elements. All had at least two elements that overlapped, usually totally, each neighbour, and two that were overlapped by each neighbour. The interior structure of all ossicles revealed a lattice‐like arrangement of struts typical of cancellous bone, the whole being surrounded by thick cortical bone. The scleral ring of a 10 week gentoo chick was not completely ossified but rather had multiple small holes within it on micro‐CT. A large os opticus was present in one king penguin but in another bird of the same age and gender there was no such bone. Much smaller accessory bones were found in the posterior pole of one Snares crested and one little penguin. We conclude that the penguin scleral ring not only maintains the shape of the eye but also provides protection and a site of insertion for rectus muscles. However, the extreme variability in the os opticus suggests that it is not essential to normal function.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 07-2008
Publisher: Informa UK Limited
Date: 1987
DOI: 10.3109/02688698709034348
Abstract: A retrospective survey has been carried out of 59 patients who suffered head injury related to horse riding out of 7172 cases of head and spinal injury admitted to a regional head injury unit in the 5-year period 1980-85. Most (85%) were female, against the usual 80% male predominance of head injury, 56 were minor injuries and 3 severe, of whom 2 died. Skull fracture was present in 10 patients (17%) of whom at least 5 had been wearing headgear at impact, and scalp trauma was noted in 22 (37%) with a predominance of occipital injuries. All the severely injured cases had an occipital skull fracture. One fifth of the patients suffered additional significant injuries. While most patients (90%) made a good recovery, 2 remained moderately and one severely disabled. Horse riding posed a significant risk of head injury to the population of riders, mainly young women. This survey suggests that the wearing of amateur riding headgear does not adequately protect the rider from scalp and skull injury, particularly in the occipital region.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 05-2016
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 12-2012
Publisher: Informa UK Limited
Date: 05-2014
DOI: 10.1111/CXO.12110
Abstract: Traditionally, photodynamic therapy (PDT) has been used to treat choroidal neovascularisation. More recently, its use in corneal neovascularisation has provided promising clinical results. The major advantage of PDT is that it is minimally invasive, resulting in closure of the neovascular network without damaging the surrounding healthy tissue. This report describes the positive results of PDT, clinically and microstructurally, as imaged by in vivo confocal microscopy, for treating corneal neovascularisation with lipid keratopathy, secondary to herpes zoster infection.
Publisher: Wiley
Date: 26-04-2022
DOI: 10.1111/CEO.14083
Abstract: To investigate repair of iris defects by endocapsular implantation of an artificial iris, in relation to visual outcomes, safety profile and patient satisfaction. Retrospective, consecutive case series from Greenlane tertiary teaching hospital and Eye Institute, Auckland, New Zealand. Medical records of patients implanted with an endocapsular artificial iris were reviewed and followed for minimum 3 months. Patient characteristics, surgical management, clinical outcomes and subjective responses were recorded. Nineteen artificial irises were implanted in 18 patients. Etiologies were iris melanotic lesion excision (73.7%), trauma (10.5%), congenital aniridia (10.5%) and Urrets-Zavalia syndrome (5.3%). During postoperative follow-up [14.1 ± 12.4 months (range: 3 to 59 months)], best corrected visual acuity (BCVA) and intraocular pressure (IOP) did not change significantly [BCVA, 0.23 logarithm of the minimum angle of resolution (logMAR) (20/32 Snellen) preoperatively vs. 0.18 logMAR postoperatively (20/25 Snellen) (Z = -0.222, p = 0.824) IOP, 15 mmHg preoperatively vs. 17 mmHg postoperatively (Z = 1.377, p = 0.1447)]. Mild or self-limiting complications included: elevated IOP (42.1%), cystoid macular oedema (15.8%) persisting postoperative uveitis (15.8%) and minor vaulting of the prosthesis (15.7%). Moderate or severe complications included significant vaulting of prosthesis requiring surgical revision (5.3%) and a single eye (5.3%) with trabeculectomy and corneal graft failure. 94.4% of patients were very satisfied with the cosmesis and would be highly likely to have the procedure again. This study confirms that endocapsular insertion of an artificial iris is typically associated with good functional and cosmetic results and a relatively low risk of significant complications.
Publisher: Association for Research in Vision and Ophthalmology (ARVO)
Date: 12-2008
DOI: 10.1167/IOVS.07-1260
Abstract: In the adult cornea, epithelial cells are maintained by limbal stem cells (LSCs) that cycle slowly and give rise to transient lifying (TA) cells. These migrate centripetally, differentiate outward to the surface, and are then lost by desquamation. This study was conducted to analyze the contribution of human central corneal epithelial cells toward corneal epithelial regeneration. A human corneal organotypic culture model was used to assess corneal healing in vitro in 12 matched cornea pairs. Two types of ablation were studied: (1) A ring-shaped, transepithelial, excimer laser (193 nm) ablation, of 7 mm outer diameter and 3 mm inner diameter, to a depth of 80 mum-sparing the central and peripheral corneal epithelium and (2) an ablation pattern identical to that in (1) with ablation of the limbal epithelium in addition. Corneal healing was followed using time-lapse dark-field microscopy for up to 12 hours, and the corneas were analyzed by using immunohistochemical markers for cell proliferation and stem cells. In the donut model, corneal epithelial repair originated from both the limbus and the central corneal epithelium with the average rate of epithelial recovery from the center being similar to the rate from the periphery (0.06 +/- 0.01 mm/h vs. 0.07 +/- 0.03 mm/h, P = 0.44). When the area of recovery was calculated relative to original edge circumferences, the central epithelial rate tended to be faster than the peripheral (0.06 +/- 0.02 mm(2)/mm/h vs. 0.04 +/- 0.01 mm(2)/mm/h, P = 0.04). Similar rates in epithelial recovery were identified in centripetal and centrifugal directions in both the donut and donut+limbus ablation models. Central epithelial cell density increased 36% over the control cornea within 12 hours after surgery, but there was no change at the periphery. Cell proliferation, assessed using Ki67 and BrdU labeling, was observed across the entire cornea. Expression of the putative stem cell markers p63 and ABCG2 was clearly evident in the basal layer of the limbus. However, weaker labeling was also observed in the central epithelium. Connexin 43 (Cx43), a differentiation marker, was mainly absent in the normal untreated limbal basal cells, but more Cx43-positive cells were labeled in the basal layer of the limbus after wounding. After wounding, the capacity for epithelial cell proliferative and migration appears to be as active in the central cornea as in the periphery/limbus. Central and peripheral epithelial recovery remains equal even after ablation of the limbus. Central human corneal epithelial cells are therefore capable of corneal epithelial regeneration, at least in the first 12 hours after wounding.
Publisher: Informa UK Limited
Date: 05-2014
DOI: 10.1111/CXO.12111
Publisher: Elsevier BV
Date: 09-2016
DOI: 10.1016/J.EXER.2016.01.002
Abstract: Macromolecular cell markers are essential for the classification and characterization of the highly complex and cellularly erse vertebrate retina. Although a plethora of markers are described in the current literature, the immunoreactivity of these markers in normal human tissue has not been fully determined. This is problematic as they are quintessential to the characterization of morphological changes associated with human retinal disease. This review provides an overview of the macromolecular markers currently available to assess human retinal cell types. We draw on immunohistochemical studies conducted in our laboratories to describe marker immunoreactivity in human retina alongside comparative descriptions in non-human tissues. Considering the growing number of eye banks services offering healthy and diseased human retinal tissue, this review provides a point of reference for future human retina studies and highlights key species specific disease applications of some macromolecular markers.
Publisher: Wiley
Date: 20-10-2012
DOI: 10.1111/J.1442-9071.2011.02671.X
Abstract: To evaluate efficacy, safety and predictability of apodized, diffractive multifocal intraocular lenses. Prospective, observational study. PARTICIPANTS OR SAMPLE: Two hundred three patients (363 eyes) underwent surgery for cataract (54.8%) or clear lens extraction (45.2%). A study of consecutive patients undergoing lens extraction with insertion of the AcrySof Natural ReSTOR intraocular lens (SN60D3). Assessment included: refraction, corneal topography, biometry, monocular and binocular uncorrected and best spectacle corrected distance and near visual acuity. Visual acuity, spectacle dependence. Mean preoperative best corrected visual acuity was 6/12 (cataract) and 6/6 (clear lens extraction). One hundred sixty-one (98.2%) of the clear lens extraction group were hyperopic and presbyopic (mean spherical equivalent +4.25±3.5D). Postoperatively uncorrected visual acuity was ≥6/12 in 96.5% of eyes (51.9% ≥6/6) and ≥ N5 in 95% of eyes. At 6 months, 182 eyes (91.4%) (cataract) and 137 eyes (83.5%) (clear lens extraction) were ≤0.50 D of target spherical equivalent. Spectacle independence was reported in 81.9% (n=168). Minor halos or other visual phenomena were reported in 10.2%. No subjects required intraocular lens exchange. Safety index at 6 months was 2.5 and 1.17 for cataract and clear lens extraction, respectively. The apodized, diffractive multifocal intraocular lens predictably provided excellent near uncorrected visual acuity and good distance uncorrected visual acuity following cataract and clear lens extraction surgery with a high rate of spectacle independence. A minority of subjects note halos and other visual phenomena that may be related to intraocular lens design.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 07-2016
DOI: 10.1016/J.JCRS.2016.04.019
Abstract: To analyze corneal haze after corneal collagen crosslinking (CXL) for progressive keratoconus using Scheimpflug densitometry. Auckland District Health Board, Auckland, New Zealand. Prospective randomized controlled study. Both eyes of all patients were examined preoperatively and 1, 3, 6, and 12 months postoperatively. One eye of each patient was treated with corneal CXL, with the contralateral eye serving as the control. Examinations included uncorrected distance visual acuity and corrected distance visual acuity (CDVA), slitl biomicroscopy, and Scheimpflug tomography (Pentacam). Thirty-six eyes of 36 patients were enrolled. The mean preoperative corneal densitometry was 19.0 ± 3.2 (SD). Postoperatively, the mean densitometry peaked at 1 month, decreasing to baseline level after 6 months without application of topical corticosteroids. The development of haze was significant compared with the contralateral untreated eyes (P < .01). The anterior (120 μm) and inner (central 0.0 to 2.0 mm) zones of the cornea had the highest densitometry after treatment. Lower preoperative central corneal thickness (CCT) was significantly correlated with higher corneal densitometry (P = .03). However, the preoperative CCT, keratometry, and astigmatism did not influence the difference in densitometry between the treated eyes and untreated eyes. There was no evidence of a relationship between densitometry and CDVA (P = .30). After corneal CXL, patients with keratoconus developed transient corneal haze in the anterior central cornea that might not require specific treatment. Thin corneas were associated with higher densitometry thus, there might be a greater expectancy of corneal haze in patients with advanced keratoconus. None of the authors has a financial or proprietary interest in any material or method mentioned.
Publisher: BMJ
Date: 16-03-2009
Abstract: Topical and subconjunctival corticosteroids are some of the most effective and compelling treatment options in ocular inflammatory diseases. A systematic review of literature indexed by Ovid MEDLINE & EMBASE was performed up to December 2008. There are few studies on their aqueous penetration in human subjects. This review article discusses the penetration of different ocular corticosteroids into human aqueous humour along with the therapeutic implications on management of ocular surface diseases, immune-related corneal diseases, anterior uveitis and postoperative anti-inflammatory use. In the context of the paucity of well-constructed, prospective clinical trials comparing the efficacy of different corticosteroids, it provides guiding principles for the use of topical corticosteroids. Dexamethasone alcohol 0.1% and prednisolone acetate 1% are potent corticosteroids, but the latter achieves the highest aqueous concentration within 2 h and maintains higher levels for 24 h. Subconjunctival corticosteroids provide very high concentrations in the aqueous which maintain higher concentrations for longer periods.
Publisher: Association for Research in Vision and Ophthalmology (ARVO)
Date: 08-09-2015
Abstract: To determine the inflammatory cell and matrix changes in advanced keratoconus, including acute hydrops, using immunohistochemical analysis. The corneal tissue from eight subjects with keratoconus undergoing corneal transplantation (three keratoconic buttons, five buttons post acute hydrops—one of them with extensive neovascularization following hydrops) was compared with tissue from two normal corneoscleral rims (n = 10). The corneas were sectioned and analyzed with specific markers for macrophages, lymphocytes, dendritic cells, and scar associated matrix molecules laminin, fibronectin, tenascin-C, and type III collagen. Populations of cells using markers for macrophages, leucocytes and antigen presenting cells were found to be associated with the epithelium and stroma of keratoconic tissue. Populations of these cells appeared decreased in hydrops-associated keratoconus except for a large increase in leucocytes in the stroma and endothelium associated with neovascularization. Extracellular matrix deposition was found to be uniquely demonstrated in localized areas of the stroma, corresponding to the site of hydrops involvement. Immunohistochemical analysis revealed a chronic, inflammatory process with recruitment of immunoinflammatory cells and deposition of scar tissue in keratoconus. The inflammatory markers were somewhat attenuated in hydrops-associated keratoconus corneas and thus inflammation was not considered to be a major factor in the development of acute corneal hydrops.
Publisher: Elsevier BV
Date: 03-2012
DOI: 10.1016/J.AJO.2011.08.020
Abstract: To compare intraocular pressure (IOP) measurements after penetrating keratoplasty (PK) using Goldmann applanation tonometry (GAT Haag-Streit USA), TonoPen XL (Reichert Inc), Pascal Dynamic Contour tonometer (PDCT Swiss Microtechnology AG), and Ocular Response Analyzer (ORA Reichert Inc) and to analyze effects and correlation of corneal thickness and curvature on these measurements. Prospective, cross-sectional study. Departments of Ophthalmology, University of Auckland and Auckland District Health Board, New Zealand. Thirty-one eyes of 31 participants with previous PK. IOP measured using GAT, TonoPen, PDCT, and ORA. Central corneal thickness (CCT) and corneal astigmatism were assessed by Pentacam rotating Scheimpflug tomography. Degree of agreement in IOP measures and correlation with CCT and corneal astigmatism. Mean age was 44.5 ± 21.0 years and mean time since PK was 27.7 ± 28.2 months (range 3.0-122.4 months). Mean CCT was 585 ± 149 μm and mean corneal astigmatism 5.5 ± 3.8 diopters. There was no significant difference in IOP measured by GAT and TonoPen however, both PDCT (2.12 mm Hg, P < .01) and ORA (6.29 mm Hg, P < .01) measured significantly higher IOPs compared to GAT. ORA showed the least agreement with GAT. Significant correlation was identified between each pair of measurement techniques. No instruments correlated significantly with CCT. Only PDCT showed no significant correlation with corneal astigmatism. However, no IOP measures correlated with corneal astigmatism if sutures in situ or less than 1 year post-PK. TonoPen or PDCT are the most suitable alternatives for measuring IOP in PK eyes where GAT readings are difficult to obtain. PDCT also offers the advantage of being independent of both CCT and corneal astigmatism.
Publisher: Springer Science and Business Media LLC
Date: 09-1991
DOI: 10.1038/EYE.1991.112
Abstract: Personalized medicine is defined by the use of genomic signatures of patients to assign effective therapies. We present Classification by Ensembles from Random Partitions (CERP) for class prediction and apply CERP to genomic data on leukemia patients and to genomic data with several clinical variables on breast cancer patients. CERP performs consistently well compared to the other classification algorithms. The predictive accuracy can be improved by adding some relevant clinical/histopathological measurements to the genomic data.
Publisher: BMJ
Date: 29-04-2014
DOI: 10.1136/BJOPHTHALMOL-2013-304145
Abstract: To analyse the clinical and microstructural changes during the course of acute corneal hydrops in keratoconus. A prospective study of consecutive patients presenting with acute corneal hydrops over 12 months was performed. Patients were examined with slit-l biomicroscopy and in vivo confocal microscopy (IVCM) at 2-weekly intervals until resolution of hydrops. 10 consecutive patients (mean age 23.6±7.5 years) were recruited. All were of Maori or Pacific Island Nations origin. All affected eyes exhibited extensive grade 3 acute corneal hydrops. Mean best corrected vision in hydrops eyes was 2/60 at presentation and 6/48 at resolution. Mean time to resolution of hydrops was 9.9±4.3 weeks. On IVCM, four corneas exhibited hyper-reflective round cells in the epithelium and stroma. Elongated branching cells with small cell bodies were noted in the anterior stroma in two cases at 6 and 12 weeks, respectively. Three months after presentation, both cases also exhibited unusual stromal cells with large speckled cell bodies and elongated branching cell processes. Both cases subsequently developed corneal neovascularisation. Corneal neovascularisation occurred in 20% of eyes in this pilot study and prolonged presence of presumed inflammatory cells was observed in these eyes. Further study of this potential association may enable identification of patients at risk of neovascularisation.
Publisher: Wiley
Date: 03-12-2019
DOI: 10.1111/CEO.13439
Abstract: Open-globe injuries (OGI) are a leading cause of monocular blindness world-wide with considerable cost to the in idual and society. To characterize the epidemiology, severity and outcomes of OGI treated at a major ophthalmology centre in New Zealand. Retrospective study. A total of 385 eyes of 381 patients over a 10-year period. Eligible patients were identified using diagnosis and surgery codes on hospital discharge summaries. Clinical notes were reviewed to determine patient demographics, injury details, treatments and outcomes. Complications of injury, visual acuity at 3 months and final follow-up, and final status of the eye. The estimated annual incidence of OGI was 2.8 per 100 000. Working-age males predominated but age at injury ranged from 9 months to 90 years. Maori and Pacific peoples were over-represented. Injuries were severe with 58.7% presenting with vision of hand movements or worse. Penetrating injuries (56.4%) were most common, followed by globe ruptures (35.6%). Major complications included retinal detachment (15.8%), enucleation/evisceration (9.1%), phthisis bulbi (9.9%), endophthalmitis (2.6%) and sympathetic ophthalmia (0.26%). Despite the injury severity, 46% of eyes achieved final BCVA of ≥6/12. The Ocular Trauma Score (OTS) was a useful prognostic tool for stratifying severity of injury and predicting visual outcome (Fisher's exact test P < 0.001). The incidence and severity of OGI in NZ are comparable to global statistics. Surgical repair can effectively recover vision, predicted well by the OTS. We identified at-risk groups to target with education and prevention strategies.
Publisher: Medknow
Date: 2013
Publisher: BMJ
Date: 11-1992
Publisher: Wiley
Date: 27-11-2020
DOI: 10.1111/CEO.13677
Abstract: Keratoplasty is a surgical procedure to create a more regular optical surface following biomechanical weakening of the cornea in keratoconus. The ideal keratoplasty procedure should also restore corneal biomechanics to that of the healthy cornea. This study aimed to evaluate and compare the biomechanical properties of corneas following penetrating keratoplasty (PKP) and predescematic deep anterior lamellar keratoplasty (DALK) to those of healthy eyes. Prospective cross-sectional study. Two cohorts of post-keratoplasty eyes (42 eyes with PKP and 27 eyes with DALK) with each other, and with a cohort of 152 healthy eyes. All eyes were examined by slit-l biomicroscopy, tomography, anterior segment-OCT and non-contact tonometry CorVis ST (CST). CST biomechanical parameters, maximum corneal deformation (MCD) and corneal energy dissipation were compared between keratoplasty techniques, and with healthy eyes. The mean age of participants with PKP and DALK were 35 ± 13.7 and 36.1 ± 12.6 years, respectively. None of the CST parameters were significantly different between PKP and DALK eyes. However, when compared to healthy corneas, numerous parameters were significantly different for both keratoplasty techniques. Of note, MCD was significantly higher in PKP compared to DALK and healthy corneas, after controlling for co-factors. Neither type of keratoplasty technique utilized in keratoconus completely restored corneal biomechanical properties to that of healthy corneas. However, PKP resulted in a greater number of parameters significantly different to healthy corneas, compared to DALK.
Publisher: Wiley
Date: 04-2012
Publisher: Association for Research in Vision and Ophthalmology (ARVO)
Date: 07-2008
DOI: 10.1167/IOVS.07-0968
Abstract: The exact pathophysiological processes underlying keratoconus remain an enigma. In this study, laser scanning in vivo confocal microscopy (IVCM) was used to define further the microstructural abnormalities in the keratoconic cornea and to establish the relationship with disease severity. This was a prospective, cross-sectional study comparing 52 subjects with keratoconus and 52 age-matched control subjects. Assessment included demographics, history, slit l biomicroscopy, computerized corneal tomography, and laser scanning IVCM. Significantly lower cell densities (in cells per square millimeter, mean +/- SD) were observed in keratoconus corneas than in normal ones: basal epithelial cells, 4340.6 +/- 595.2 vs. 5777.6 +/- 958.2 (P < 0.001), anterior keratocytes, 523.6 +/- 206.4 vs. 859.7 +/- 219.1 (P < 0.001), posterior keratocytes, 240.4 +/- 64.5 vs. 330.6 +/- 52.3 (P < 0.001), and endothelial cells 2412.2 +/- 339.5 vs. 2845.6 +/- 313.0 (P < 0.001). Subbasal nerve fiber density was 52.7% lower in keratoconus corneas than in the control (P < 0.001). Basal epithelial cell density (P = 0.001), subbasal nerve fiber density (P = 0.015), and anterior keratocyte density (P < 0.001) correlated with severity of disease. Lower subbasal nerve density also correlated with younger age at diagnosis (r = 0.397, P = 0.004). Severe disease was associated with diagnosis at a younger age (P = 0.023), a history of eye rubbing (P = 0.025), and Maori or Pacific Island ethnicity (P = 0.001). Significant microstructural abnormalities were identified at every level of the keratoconic cornea and were related to disease severity. IVCM offers a potential insight into the pathophysiology of the microstructural changes in keratoconus.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 08-02-2022
Publisher: Elsevier BV
Date: 02-2021
Publisher: Elsevier BV
Date: 09-2014
Publisher: Wiley
Date: 08-2001
DOI: 10.1046/J.1442-9071.2001.00432.X
Abstract: To identify features of posterior polymorphous dystrophy (PPMD) by in vivo confocal microscopy, the corneas of a female patient with PPMD were exam ned using slit-l biomicroscopy and slit-scanning in vivo confocal microscopy. Characteristic endothelial vesicular and band lesions were seen clinically and easily identified using in vivo confocal microscopy. However endothelial pleomorphism, an increased density and reflectance of posterior stromal keratocytes, and prominence of corneal nerves were also delineated. In vivo confocal microscopy enhances clinicopathological diagnosis and follow up of corneal dystrophies with subtle clinical presentations, such as PPMD.
Publisher: Springer Science and Business Media LLC
Date: 08-02-2008
Abstract: Despite the importance of a healthy endothelial layer in anterior segment surgery, the possible influence of corneal parameters on endothelial cell density (ECD) has largely been ignored in the young adult eye. This study investigated the possible associations between corneal tomographic parameters and ECD values in young adults. Subjects aged 21-30 years, with normal corneas were recruited. Mean ECD, mean cell area (MCA), coefficient of variation for cell area (COVA), and proportion of hexagonal cells were derived by in vivo confocal microscopy. The Orbscan II system was used to measure corneal parameters including: thickness, horizontal corneal diameter, corneal curvature, anterior and posterior elevation, and eccentricity. Sixty-two subjects (42 female, 20 male) were included (mean age 25+/-3 years). Overall mean ECD was 3169+/-309 cells/mm(2) with no differences between genders. Mean percentage of hexagonality was 53+/-5%, male subjects (55%) had a higher percentage of hexagonal cells than female subjects (51%) (P=0.02). Central corneal thickness (CCT) was 529+/-43 microm. Central ECD was significantly correlated with CCT (Pearson's r=0.26, P=0.04). However, horizontal corneal diameter (r=0.19, P=0.14), anterior corneal curvature (r=-0.07, P=0.6), and posterior corneal curvature (r=-0.07, P=0.6) were not correlated with ECD or percentage of hexagonality. There was no statistically significant association between anterior chamber depth (3.6+/-0.3 mm) and ECD (r=0.15, P=0.3). Corneal thickness is related to ECD in normal young adult eye, with lower ECD values identified in thinner corneas however, corneal diameter and corneal curvature do not have a significant correlation with ECD.
Publisher: Wiley
Date: 05-06-2018
DOI: 10.1111/CEO.13320
Publisher: BMJ
Date: 08-2004
Publisher: Wiley
Date: 04-01-2019
DOI: 10.1111/CEO.13443
Abstract: This is the first national study on childhood visual impairment in a developed nation, New Zealand, describing prevalence, aetiology and preventable causes of low vision and blindness in children. Causes of childhood blindness vary between regions. This study aimed to present region-specific data on epidemiology of childhood blindness affecting a developed nation, New Zealand. Retrospective data analysis. All children enrolled with the Blind and Low Vision Education Network New Zealand (BLENNZ) with best-corrected visual acuity ≤6/18, or binocular visual field <10°. 1000 out of 1321 children with visual impairment enrolled with BLENNZ were included. The principal cause of visual loss was determined, and the severity of visual loss categorized as low vision, or blindness according to the World Health Organization criteria. Main outcome measures were degree of visual impairment, aetiology of visual impairment and treatment modalities for visual rehabilitation. The calculated prevalence of childhood blindness and low vision was 0.05% and 0.06%. Principle causes of blindness were cortical visual impairment (31.5%), optic nerve atrophy (16.5%) and optic nerve hypoplasia (9.0%). The main preventable causes of blindness were neonatal trauma/asphyxia (31.5%), retinopathy of prematurity (18.2%) and non-accidental injury (10.3%). This is the first national report on prevalence of childhood low vision and blindness in New Zealand. The prevalence and leading causes of low vision and blindness found in this study were comparable to other developed nations however, preventable causes of low vision and blindness appeared unique to New Zealand.
Publisher: Wiley
Date: 09-12-2020
DOI: 10.1111/CEO.13685
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 03-2004
Publisher: Wiley
Date: 04-2004
DOI: 10.1111/J.1088-145X.2004.00059.X
Abstract: This study examined the relationship of family stress, severity of the stressor, uncertainty, coping, and family adaptation from pretransplantation to posttransplantation. A descriptive, longitudinal study of 15 mothers whose children were at least 5 years posttransplantation. Maternal stress, coping, and uncertainty demonstrated significant changes over time, whereas family stress did not. Pretransplantation family stress, anger, and confusion were related to poorer family adaptation. Interventions for mothers pretransplantation should account for the coping, levels of stress, and uncertainty present at each phase of the transplantation process. Interventions need to be tailored to the transplantation phase. Long-term interventions remain necessary and should be directed at reinforcement of teaching, as well as assessment and provision of parental support relevant to the long-term needs of the family.
Publisher: Wiley
Date: 27-06-2019
DOI: 10.1111/CEO.13567
Abstract: Keratoconus is a debilitating condition with a disproportionately high impact on health resources and vision-specific quality of life. This study aimed to compare 2-year outcomes of epithelium-off pulsed (p-ACXL) and epithelium-off continuous (c-ACXL) accelerated corneal crosslinking in progressive keratoconus. Prospective, interventional case series. Eighty eyes of 80 patients were included. The visual, refractive and tomographic results of the two crosslinking protocols were compared. Uncorrected distance visual acuity, corrected distance visual acuity (CDVA), manifest refraction spherical equivalent (MRSE) and maximum keratometry (K The mean patient age was 22.51 ± 6.12 years (SD) and 22.08 ± 5.72 years in the p-ACXL and c-ACXL groups, respectively. The mean CDVA significantly improved from 0.30 ± 0.16 logMAR at baseline to 0.23 ± 0.17 logMAR at 24 months (P = .04) in the p-ACXL group and from 0.36 ± 0.22 logMAR to 0.26 ± 0.27 logMAR (P = .02) in the c-ACXL group. The mean induced change in MRSE (+1.79 ± 2.30 D vs +0.27 ± 3.19 D, P = .04) and K In this prospective study, both p-ACXL and c-ACXL treatments were safe methods to halt the progression of keratoconus within a follow-up period of 24 months. c-ACXL appeared to offer superior refractive and tomographic outcomes when compared to p-ACXL but this did not translate into better visual outcomes.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 2003
DOI: 10.1097/00003226-200301000-00019
Abstract: To analyze clinical and in vivo microstructural characteristics of both corneas of a 13-year-old male subject with Scheie's syndrome and compare the observations with the pathologic reports in the literature. Standard clinical examination and real-time, slit-scanning in vivo confocal microscopy were performed and repeated after 1 year. In vivo confocal microscopy images at all cellular layers demonstrated brighter intercellular spaces than those of normal corneas. Cicatrization of the anterior stroma was identified, and the keratocytes of the middle and posterior stroma exhibited markedly altered morphology, often round or elliptical in shape, and with clearly demarcated, hyporeflective centers. The nerve fibers of the subbasal plexus were somewhat more irregular and difficult to distinguish, possibly due to underlying fibrosis. The potential of in vivo confocal microscopy to highlight microstructural alterations of the intact human cornea and evaluate such changes over time might reduce reliance on histopathologic investigations in such conditions and contribute to the ophthalmic management of the mucopolysaccharidoses in the future.
Publisher: Wiley
Date: 07-2009
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 08-2005
DOI: 10.1097/01.ICO.0000154389.51125.70
Abstract: To delineate the microstructural features of Meesmann corneal dystrophy using in vivo confocal microscopy. Three subjects with clinically diagnosed Meesmann corneal dystrophy were examined by slit-l biomicroscopy and slit-scanning in vivo confocal microscopy. On slit-l biomicroscopy, all subjects demonstrated large bilateral multiple epithelial cystic lesions extending to the midperiphery. On in vivo confocal microscopy, these lesions appeared as hyporeflective areas in the basal epithelial layer. The majority were circular, oval or teardrop shaped and ranged between 48 mum and 145 mum in diameter. Large elongated intraepithelial clefts were also seen. Reflective spots were visible within most of the lesions and these may represent the fibrillogranular material (termed peculiar substance) and tonofilament bundles observed in electron microscopy studies. An additional finding was the fragmented appearance of the subbasal nerve plexus. We present the first case series of Meesmann corneal dystrophy imaged by in vivo confocal microscopy and describe the associated microstructural features. Delineation of these features facilitates the use of the confocal microscope to aid diagnosis and management of corneal dystrophies.
Publisher: Wiley
Date: 10-2002
DOI: 10.1046/J.1442-9071.2002.00558.X
Abstract: A 44-year-old man with symptoms of ocular irritation and corneal changes characteristic of Salzmann's nodular degeneration in the left eye was examined using in vivo confocal microscopy. In vivo confocal microscopy highlighted an irregularly shaped basal epithelium with foci of prominent nuclei, and disrupted anterior stromal architecture with increased reflectivity of extracellular matrix within the nodules. These observations were consistent with prior histopathological descriptions of Salzmann's nodular degeneration. In vivo confocal microscopy enhances the clinicopathological assessment of degenerative corneal diseases, such as Salzmann's nodular degeneration, without the need for biopsy.
Publisher: Springer Science and Business Media LLC
Date: 19-04-2023
Location: Australia
Location: United Kingdom of Great Britain and Northern Ireland
Location: United Kingdom of Great Britain and Northern Ireland
Location: United Kingdom of Great Britain and Northern Ireland
Location: United Kingdom of Great Britain and Northern Ireland
Location: United Kingdom of Great Britain and Northern Ireland
No related grants have been discovered for Charles NJ McGhee.