ORCID Profile
0000-0002-9739-7280
Current Organisations
University of Manchester
,
University of Oxford
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Publisher: Elsevier BV
Date: 2020
DOI: 10.1016/J.OPHTHA.2019.08.015
Abstract: To describe and compare associations with macular retinal nerve fiber layer (mRNFL), ganglion cell complex (GCC), and ganglion cell-inner plexiform layer (GCIPL) thicknesses in a large cohort. Cross-sectional study. We included 42 044 participants in the UK Biobank. The mean age was 56 years. Spectral-domain OCT macular images were segmented and analyzed. Corneal-compensated intraocular pressure (IOPcc) was measured with the Ocular Response Analyzer (Reichert, Corp., Buffalo, NY). Multivariable linear regression was used to examine associations with mean mRNFL, GCC, and GCIPL thicknesses. Factors examined were age, sex, ethnicity, height, body mass index (BMI), smoking status, alcohol intake, Townsend deprivation index, education level, diabetes status, spherical equivalent, and IOPcc. Thicknesses of mRNFL, GCC, and GCIPL. We identified several novel independent associations with thinner inner retinal thickness. Thinner inner retina was associated with alcohol intake (most significant for GCIPL: -0.46 μm for daily or almost daily intake compared with special occasion only or never [95% confidence interval (CI), 0.61-0.30] P = 1.1×10 The novel associations we identified may be important to consider when using inner retinal parameters as a diagnostic tool. Associations generally were strongest with GCIPL, particularly for IOP. This suggests that GCIPL may be the superior inner retinal biomarker for macular pathophysiologic processes and especially for glaucoma.
Publisher: Springer Science and Business Media LLC
Date: 28-08-2015
DOI: 10.1038/EYE.2015.157
Publisher: American Medical Association (AMA)
Date: 12-2015
Publisher: Association for Research in Vision and Ophthalmology (ARVO)
Date: 11-05-2011
DOI: 10.1167/IOVS.10-6208
Abstract: To report the impact of intravitreous bevacizumab therapy on contrast sensitivity in patients with neovascular age-related macular degeneration (nAMD). This was a prospective, multicenter, double-masked, randomized, controlled trial of 131 patients with nAMD. The patients with nAMD had received intravitreal bevacizumab (n = 65) or standard therapy (n = 66) in the study eye with a 6-week cycle of assessment. The bevacizumab treatment was 1.25 mg/0.05 mL, given as three initial treatments with further retreatment as needed according to standard retreatment criteria and a 1-year (54-week) follow-up. Contrast sensitivity was determined during the study using a Pelli-Robson chart. At the week-54 examination, bevacizumab-treated patients were more likely to gain at least 6 letters or more of contrast sensitivity than the patients receiving standard care (23 [35.4%] versus 10 [15.2%], P = 0.009). In addition the bevacizumab-treated patients were less likely to lose 6 or more letters with a better mean letter change at week 54 than the patients receiving standard care (3 [4.6%] versus 14 [21.2%], and +4.0 versus -0.7 letters P < 0.05 for both comparisons). Consistent with the visual acuity outcomes, bevacizumab improved the chances of a clinically relevant gain in contrast sensitivity in the study population. Given the association between contrast sensitivity and visual disability, the beneficial effects of bevacizumab therapy on contrast sensitivity outcomes are expected to have a favorable impact on patients' daily activities. (www.controlled-trials.com number, ISRCTN83325075.).
Publisher: Public Library of Science (PLoS)
Date: 22-05-2015
Publisher: Springer Science and Business Media LLC
Date: 27-11-2019
DOI: 10.1038/S42003-019-0634-9
Abstract: A new avenue of mining published genome-wide association studies includes the joint analysis of related traits. The power of this approach depends on the genetic correlation of traits, which reflects the number of pleiotropic loci, i.e. genetic loci influencing multiple traits. Here, we applied new meta-analyses of optic nerve head (ONH) related traits implicated in primary open-angle glaucoma (POAG) intraocular pressure and central corneal thickness using Haplotype reference consortium imputations. We performed a multi-trait analysis of ONH parameters cup area, disc area and vertical cup-disc ratio. We uncover new variants rs11158547 in PPP1R36-PLEKHG3 and rs1028727 near SERPINE3 at genome-wide significance that replicate in independent Asian cohorts imputed to 1000 Genomes. At this point, validation of these variants in POAG cohorts is h ered by the high degree of heterogeneity. Our results show that multi-trait analysis is a valid approach to identify novel pleiotropic variants for ONH.
Publisher: Elsevier BV
Date: 04-2016
Publisher: Springer Science and Business Media LLC
Date: 22-08-2019
DOI: 10.1038/S41746-019-0154-5
Abstract: Uncorrected refractive error is a major cause of vision impairment, and is indexed by visual acuity. Availability of vision assessment is limited in low/middle-income countries and in minority groups in high income countries. eHealth tools offer a solution two-thirds of the globe own mobile devices. This is a scoping review of the number and quality of tools for self-testing visual acuity. Software applications intended for professional clinical use were excluded. Keyword searches were conducted on Google online, Google Play and iOS store. The first 100 hits in each search were screened against inclusion criteria. After screening, 42 tools were reviewed. Tools assessed near and distance vision. About half ( n = 20) used bespoke optotypes. The majority ( n = 25) presented optotypes one by one. Four included a calibration procedure. Only one tool was validated against gold standard measures. Many self-test tools have been published, but lack validation. There is a need for regulation of tools for the self-testing of visual acuity to reduce potential risk or confusion to users.
Publisher: Springer Science and Business Media LLC
Date: 28-05-2018
Publisher: Elsevier BV
Date: 04-2016
DOI: 10.1016/J.OPHTHA.2015.11.009
Abstract: To derive macular thickness measures and their associations by performing rapid, automated segmentation of spectral-domain optical coherence tomography (SD OCT) images collected and stored as part of the UK Biobank (UKBB) study. Large, multisite cohort study in the United Kingdom. Analysis of cross-sectional data. Adults from the United Kingdom aged 40 to 69 years. Participants had nonmydriatic SD OCT (Topcon 3D OCT-1000 Mark II Topcon GB, Newberry, Berkshire, UK) performed as part of the ocular assessment module. Rapid, remote, automated segmentation of the images was performed using custom optical coherence tomography (OCT) image analysis software (Topcon Advanced Boundary Segmentation [TABS] Topcon GB) to generate macular thickness values. We excluded people with a history of ocular or systemic disease (diabetes or neurodegenerative diseases) and eyes with reduced vision (<0.1 logarithm of the minimum angle of resolution) or with low SD OCT signal-to-noise ratio and low segmentation success certainty. Macular thickness values across 9 Early Treatment of Diabetic Retinopathy Study (ETDRS) subfields. The SD OCT scans of 67 321 subjects were available for analysis, with 32 062 people with at least 1 eye meeting the inclusion criteria. There were 17 274 women and 14 788 men, with a mean (standard deviation [SD]) age of 55.2 (8.2) years. The mean (SD) logarithm of the minimum angle of resolution visual acuity was -0.075 (0.087), and the refractive error was -0.071 (+1.91) diopters (D). The mean (SD) central macular thickness (CMT) in the central 1-mm ETDRS subfield was 264.5 (22.9) μm, with 95% confidence limits of 220.8 and 311.5 μm. After adjusting for covariates, CMT was positively correlated with older age, female gender, greater myopia, smoking, body mass index (BMI), and white ethnicity (all P < 0.001). Of note, macular thickness in other subfields was negatively correlated with older age and greater myopia. We report macular thickness data derived from SD OCT images collected as part of the UKBB study and found novel associations among older age, ethnicity, BMI, smoking, and macular thickness.
Publisher: Public Library of Science (PLoS)
Date: 02-10-2015
Publisher: Elsevier BV
Date: 2006
DOI: 10.1016/J.PRETEYERES.2005.07.001
Abstract: As digital imaging and computing power increasingly develop, so too does the potential to use these technologies in ophthalmology. Image processing, analysis and computer vision techniques are increasing in prominence in all fields of medical science, and are especially pertinent to modern ophthalmology, as it is heavily dependent on visually oriented signs. The retinal microvasculature is unique in that it is the only part of the human circulation that can be directly visualised non-invasively in vivo, readily photographed and subject to digital image analysis. Exciting developments in image processing relevant to ophthalmology over the past 15 years includes the progress being made towards developing automated diagnostic systems for conditions, such as diabetic retinopathy, age-related macular degeneration and retinopathy of prematurity. These diagnostic systems offer the potential to be used in large-scale screening programs, with the potential for significant resource savings, as well as being free from observer bias and fatigue. In addition, quantitative measurements of retinal vascular topography using digital image analysis from retinal photography have been used as research tools to better understand the relationship between the retinal microvasculature and cardiovascular disease. Furthermore, advances in electronic media transmission increase the relevance of using image processing in 'teleophthalmology' as an aid in clinical decision-making, with particular relevance to large rural-based communities. In this review, we outline the principles upon which retinal digital image analysis is based. We discuss current techniques used to automatically detect landmark features of the fundus, such as the optic disc, fovea and blood vessels. We review the use of image analysis in the automated diagnosis of pathology (with particular reference to diabetic retinopathy). We also review its role in defining and performing quantitative measurements of vascular topography, how these entities are based on 'optimisation' principles and how they have helped to describe the relationship between systemic cardiovascular disease and retinal vascular changes. We also review the potential future use of fundal image analysis in telemedicine.
Publisher: Springer Science and Business Media LLC
Date: 26-11-2019
DOI: 10.1038/S41746-019-0195-9
Abstract: An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Publisher: BMJ
Date: 09-06-2010
DOI: 10.1136/BMJ.C2459
Abstract: To evaluate the efficacy and safety of intravitreous bevacizumab injections for the treatment of neovascular age related macular degeneration. Prospective, double masked, multicentre, randomised controlled trial. Three ophthalmology centres in the United Kingdom. 131 patients (mean age 81) with wet age related macular degeneration randomised 1:1 to intervention or control. Intravitreous bevacizumab (1.25 mg, three loading injections at six week intervals followed by further treatment if required at six week intervals) or standard treatment available at the start of the trial (photodynamic treatment with verteporfin for predominantly classic type neovascular age related macular degeneration, or intravitreal pegaptanib or sham treatment for occult or minimally classic type neovascular age related macular degeneration). proportion of patients gaining >or=15 letters of visual acuity at one year (54 weeks). proportion of patients with stable vision and mean change in visual acuity. Of the 131 patients enrolled in the trial, five patients did not complete the study because of adverse events, loss to follow-up, or death. In the bevacizumab group, 21 (32%) patients gained 15 or more letters from baseline visual acuity compared with two (3%) in the standard care group (P<0.001) the estimated adjusted odds ratio was 18.1 (95% confidence interval 3.6 to 91.2) and the number needed to treat was 4 (3 to 6). In addition, the proportion of patients who lost fewer than 15 letters of visual acuity from baseline was significantly greater among those receiving bevacizumab treatment (91% (59) v 67% (44) in standard care group P<0.001). Mean visual acuity increased by 7.0 letters in the bevacizumab group with a median of seven injections compared with a decrease of 9.4 letters in the standard care group (P<0.001), and the initial improvement at week 18 (plus 6.6 letters) was sustained to week 54. Among 65 patients treated with bevacizumab, there were no cases of endophthalmitis or serious uveitis related to the intervention. All end points with respect to visual acuity in the study eye at 54 weeks favoured bevacizumab treatment over standard care. Bevacizumab 1.25 mg intavitreous injections given as part of a six weekly variable retreatment regimen is superior to standard care (pegaptanib sodium, verteporfin, sham), with low rates of serious ocular adverse events. Treatment improved visual acuity on average at 54 weeks. Trial registration number Current controlled trials ISRCTN83325075.
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 Tariq Aslam.