ORCID Profile
0000-0002-2967-4792
Current Organisations
University of California, San Diego
,
Johns Hopkins University
,
Massachusetts Eye and Ear
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Publisher: BMJ
Date: 30-01-2019
DOI: 10.1136/BJOPHTHALMOL-2018-313207
Abstract: Syphilitic uveitis is re-emerging alongside the systemic infection. In July 2017, an international group of uveitis-specialised ophthalmologists formed the International Ocular Syphilis Study Group to define current practice patterns. 103 Study Group members based in 35 countries completed a 25-item questionnaire focused on case load, clinical presentations, use and interpretation of investigations, treatment and clinical indicators of poor prognosis. Members managed a mean of 6.1 patients with syphilitic uveitis in clinics that averaged 707 annual cases of uveitis (0.9%) 53.2% reported increasing numbers over the past decade. Patients presented to more members (40.2%) during secondary syphilis. Uveitis was usually posterior (60.8%) or pan (22.5%) complications included optic neuropathy, macular oedema and posterior synechiae. All members diagnosed syphilitic uveitis using serological tests (simultaneous or sequential testing algorithms), and 97.0% routinely checked for HIV co-infection. Cerebrospinal fluid (CSF) analysis was ordered by 90.2% of members, and 92.7% took uveitis plus Venereal Disease Research Laboratory test (VDRL) or fluorescent treponemal antibody absorption test (FTA-ABS) to indicate neurosyphilis. Patients were commonly co-managed with infectious disease physicians, and treated with penicillin for at least 10–14 days, plus corticosteroid. Features predicting poor outcome included optic neuropathy (86.3%) and initial misdiagnosis (63.7%). Reasons for delayed diagnosis were often practitioner-related. 82.5% of members tested every patient they managed with uveitis for syphilis. This comprehensive report by an international group of uveitis-specialised ophthalmologists provides a current approach for the management of syphilitic uveitis.
Publisher: BMJ
Date: 15-03-2018
DOI: 10.1136/BJOPHTHALMOL-2017-311258
Abstract: Within a surveillance of the prevalence and causes of vision impairment in high-income regions and Central/Eastern Europe, we update figures through 2015 and forecast expected values in 2020. Based on a systematic review of medical literature, prevalence of blindness, moderate and severe vision impairment (MSVI), mild vision impairment and presbyopia was estimated for 1990, 2010, 2015, and 2020. Age-standardised prevalence of blindness and MSVI for all ages decreased from 1990 to 2015 from 0.26% (0.10–0.46) to 0.15% (0.06–0.26) and from 1.74% (0.76–2.94) to 1.27% (0.55–2.17), respectively. In 2015, the number of in iduals affected by blindness, MSVI and mild vision impairment ranged from 70 000, 630 000 and 610 000, respectively, in Australasia to 980 000, 7.46 million and 7.25 million, respectively, in North America and 1.16 million, 9.61 million and 9.47 million, respectively, in Western Europe. In 2015, cataract was the most common cause for blindness, followed by age-related macular degeneration (AMD), glaucoma, uncorrected refractive error, diabetic retinopathy and cornea-related disorders, with declining burden from cataract and AMD over time. Uncorrected refractive error was the leading cause of MSVI. While continuing to advance control of cataract and AMD as the leading causes of blindness remains a high priority, overcoming barriers to uptake of refractive error services would address approximately half of the MSVI burden. New data on burden of presbyopia identify this entity as an important public health problem in this population. Additional research on better treatments, better implementation with existing tools and ongoing surveillance of the problem is needed.
Publisher: BMJ
Date: 28-08-2019
DOI: 10.1136/BJOPHTHALMOL-2018-313308
Abstract: To determine the prevalence and causes of blindness and vision impairment (VI) in East Asia in 2015 and to forecast the trend to 2020. Through a systematic literature review and meta-analysis, we estimated prevalence of blindness (presenting visual acuity /60 in the better eye), moderate-to-severe vision impairment (MSVI 3/60≤presenting visual acuity /18), mild vision impairment (mild VI: 6/18≤presenting visual acuity /12) and uncorrected presbyopia for 1990, 2010, 2015 and 2020. A total of 44 population-based studies were included. In 2015, age-standardised prevalence of blindness, MSVI, mild VI and uncorrected presbyopia was 0.37% (80% uncertainty interval (UI) 0.12%–0.68%), 3.06% (80% UI 1.35%–5.16%) and 2.65% (80% UI 0.92%–4.91%), 32.91% (80% UI 18.72%–48.47%), respectively, in East Asia. Cataract was the leading cause of blindness (43.6%), followed by uncorrected refractive error (12.9%), glaucoma, age-related macular degeneration, corneal diseases, trachoma and diabetic retinopathy (DR). The leading cause for MSVI was uncorrected refractive error, followed by cataract, age-related macular degeneration, glaucoma, corneal disease, trachoma and DR. The burden of VI due to uncorrected refractive error, cataracts, glaucoma and DR has continued to rise over the decades reported. Addressing the public healthcare barriers for cataract and uncorrected refractive error can help eliminate almost 57% of all blindness cases in this region. Therefore, public healthcare efforts should be focused on effective screening and effective patient education, with access to high-quality healthcare.
Publisher: WHO Press
Date: 11-2019
Publisher: Elsevier BV
Date: 12-2015
Publisher: Elsevier BV
Date: 10-2014
DOI: 10.1016/J.AJO.2014.07.003
Abstract: To determine the frequency of ocular adverse effects associated with vemurafenib (PLX4032) treatment for metastatic cutaneous melanoma. Retrospective review of the clinical study reports from the clinical pharmacology, phase 1, phase 2, and phase 3 trials of vemurafenib. The vemurafenib clinical trials were a multicenter series involving adult patients with histologically confirmed, BRAF(V600) mutation-positive, unresectable, stage IIIC or IV melanoma. A total of 855 patients were enrolled in the trials: 568 patients were treated with vemurafenib and 287 patients were treated with dacarbazine. Among the 568 patients treated with vemurafenib, ocular adverse effects developed in 22% (95% confidence interval [CI], 18.5-25.6). The most common ocular diagnosis was uveitis (4.0% 95% CI, 2.6-6.0), followed by conjunctivitis (2.8% 95% CI, 1.6-4.5) and dry eyes (2.0% 95% CI, 1.1-3.7). All were successfully managed while vemurafenib therapy was continued. Ocular adverse events and symptoms may be seen in more than one-fifth of patients being treated with vemurafenib. However, vemurafenib can be continued while the ocular symptoms are being managed. The pathogenesis of ocular symptoms in this patient population is unclear additional studies are necessary.
Publisher: Elsevier BV
Date: 11-2201
Publisher: BMJ
Date: 12-09-2018
DOI: 10.1136/BJOPHTHALMOL-2018-312068
Abstract: To assess the prevalence and causes of vision impairment in North Africa and the Middle East (NAME) from 1990 to 2015 and to forecast projections for 2020. Based on a systematic review of medical literature, the prevalence of blindness (presenting visual acuity (PVA) /60 in the better eye), moderate and severe vision impairment (MSVI PVA /18 but ≥3/60) and mild vision impairment (PVA /12 but ≥6/18) was estimated for 2015 and 2020. The age-standardised prevalence of blindness and MSVI for all ages and genders decreased from 1990 to 2015, from 1.72 (0.53–3.13) to 0.95% (0.32%–1.71%), and from 6.66 (3.09–10.69) to 4.62% (2.21%–7.33%), respectively, with slightly higher figures for women than men. Cataract was the most common cause of blindness in 1990 and 2015, followed by uncorrected refractive error. Uncorrected refractive error was the leading cause of MSVI in the NAME region in 1990 and 2015, followed by cataract. A reduction in the proportions of blindness and MSVI due to cataract, corneal opacity and trachoma is predicted by 2020. Conversely, an increase in the proportion of blindness attributable to uncorrected refractive error, glaucoma, age-related macular degeneration and diabetic retinopathy is expected. In 2015 cataract and uncorrected refractive error were the major causes of vision loss in the NAME region. Proportions of vision impairment from cataract, corneal opacity and trachoma are expected to decrease by 2020, and those from uncorrected refractive error, glaucoma, diabetic retinopathy and age-related macular degeneration are predicted to increase by 2020.
Publisher: BMJ
Date: 12-09-2018
DOI: 10.1136/BJOPHTHALMOL-2018-311946
Abstract: To assess prevalence and causes of vision impairment in South-east Asia and Oceania regions from 1990 to 2015 and to forecast the figures for 2020. Based on a systematic review of medical literature, prevalence of blindness (presenting visual acuity (PVA) /60 in the better eye), moderate and severe vision impairment (MSVI PVA /18 but ≥3/60), mild vision impairment (PVA /12 but ≥6/18) and near vision impairment ( N5 or N8 in the presence of normal vision) were estimated for 1990, 2010, 2015 and 2020. The age-standardised prevalence of blindness for all ages and both genders was higher in the Oceania region but lower for MSVI when comparing the subregions. The prevalence of near vision impairment in people≥50 years was 41% (uncertainty interval (UI) 18.8 to 65.9). Comparison of the data for 2015 with 2020 predicts a small increase in the numbers of people affected by blindness, MSVI and mild VI in both subregions. The numbers predicted for near VI in South-east Asia are from 90.68 million in 2015 to 102.88 million in 2020. The main causes of blindness and MSVI in both subregions in 2015 were cataract, uncorrected refractive error, glaucoma, corneal disease and age-related macular degeneration. There was no trachoma in Oceania from 1990 and decreasing prevalence in South-east Asia with elimination predicted by 2020. In both regions, the main challenges for eye care come from cataract which remains the main cause of blindness with uncorrected refractive error the main cause of MSVI. The trend between 1990 and 2015 is for a lower prevalence of blindness and MSVI in both regions.
Publisher: BMJ
Date: 12-09-2018
DOI: 10.1136/BJOPHTHALMOL-2017-311746
Abstract: To estimate the prevalence and causes of blindness and vision impairment for distance and near in Latin America and the Caribbean (LAC) in 2015 and to forecast trends to 2020. A meta-analysis from a global systematic review of 283 cross-sectional, population-representative studies from published and unpublished sources from 1980 to 2014 in the Global Vision Database included 17 published and 6 unpublished studies from LAC. In 2015, across LAC, age-standardised prevalence was 0.38% in all ages and 1.56% in those over age 50 for blindness 2.06% in all ages and 7.86% in those over age 50 for moderate and severe vision impairment (MSVI) 1.89% in all ages and 6.93% in those over age 50 for mild vision impairment and 39.59% in all ages and 45.27% in those over 50 for near vision impairment (NVI). In 2015, 117.86 million persons were vision impaired of those 2.34 million blind, 12.46 million with MSVI, 11.34 million mildly impaired and 91.72 million had NVI. Cataract is the most common cause of blindness. Undercorrected refractive-error is the most common cause of vision impairment. These prevalence estimates indicate that one in five persons across LAC had some degree of vision loss in 2015. We predict that from 2015 to 2020, the absolute numbers of persons with vision loss will increase by 12% to 132.33 million, while the all-age age-standardised prevalence will decrease for blindness by 15% and for other distance vision impairment by 8%. All countries need epidemiologic research to establish accurate national estimates and trends. Universal eye health services must be included in universal health coverage reforms to address disparities, fragmentation and segmentation of healthcare
Publisher: BMJ
Date: 30-03-2020
DOI: 10.1136/BJOPHTHALMOL-2019-315217
Abstract: This study aimed to assess the prevalence and causes of vision loss in sub-Saharan Africa (SSA) in 2015, compared with prior years, and to estimate expected values for 2020. A systematic review and meta-analysis assessed the prevalence of blindness (presenting distance visual acuity /60 in the better eye), moderate and severe vision impairment (MSVI presenting distance visual acuity /18 but ≥3/60) and mild vision impairment (MVI presenting distance visual acuity /12 and ≥6/18), and also near vision impairment ( N6 or N8 in the presence of ≥6/12 best-corrected distance visual acuity) in SSA for 1990, 2010, 2015 and 2020. In SSA, age-standardised prevalence of blindness, MSVI and MVI in 2015 were 1.03% (80% uncertainty interval (UI) 0.39–1.81), 3.64% (80% UI 1.71–5.94) and 2.94% (80% UI 1.05–5.34), respectively, for male and 1.08% (80% UI 0.40–1.93), 3.84% (80% UI 1.72–6.37) and 3.06% (80% UI 1.07–5.61) for females, constituting a significant decrease since 2010 for both genders. There were an estimated 4.28 million blind in iduals and 17.36 million in iduals with MSVI 101.08 million in iduals were estimated to have near vision loss due to presbyopia. Cataract was the most common cause of blindness (40.1%), whereas undercorrected refractive error (URE) (48.5%) was the most common cause of MSVI. Sub-Saharan West Africa had the highest proportion of blindness compared with the other SSA subregions. Cataract and URE, two of the major causes of blindness and vision impairment, are reversible with treatment and thus promising targets to alleviate vision impairment in SSA.
Publisher: Springer Science and Business Media LLC
Date: 29-07-2022
DOI: 10.1038/S41433-022-02190-4
Abstract: To validate the fundus image grading results by a trained grader (Non-ophthalmologist) and an ophthalmologist grader for detecting diabetic retinopathy (DR) and diabetic macular oedema (DMO) against fundus examination by a retina specialist (gold standard). A prospective diagnostic accuracy study was conducted using 2002 non-mydriatic colour fundus images from 1001 patients aged ≥40 years. Using the Aravind Diabetic Retinopathy Evaluation Software (ADRES) images were graded by both a trained non-ophthalmologist grader (grader-1) and an ophthalmologist (grader-2). Sensitivity, specificity, positive predictive value and negative predictive value were calculated for grader-1 and grader-2 against the grading results by an independent retina specialist who performed dilated fundus examination for every study participant. Out of 1001 patients included, 42% were women and the mean ± (SD) age was 55.8 (8.39) years. For moderate or worse DR, the sensitivity and specificity for grading by grader-1 with respect to the gold standard was 66.9% and 91.0% respectively and the same for the ophthalmologist was 83.6% and 80.3% respectively. For referable DMO, grader-1 and grader-2 had a sensitivity of 74.6% and 85.6% respectively and a specificity of 83.7% and 79.8% respectively. Our results demonstrate good level of accuracy for the fundus image grading performed by a trained non-ophthalmologist which was comparable with the grading by an ophthalmologist. Engaging trained non-ophthalmologists potentially can enhance the efficiency of DR diagnosis using fundus images. Further study with multiple non-ophthalmologist graders is needed to verify the results and strategies to improve agreement for DMO diagnosis are needed.
Publisher: Elsevier BV
Date: 02-2009
DOI: 10.1016/J.AJO.2008.08.019
Abstract: To report seven cases of uveitis occurring in patients with autoimmune hepatitis (AIH), raising the possibility that uveitis may be an extrahepatic feature of AIH. Multicenter, retrospective, observational case series of patients with AIH and uveitis. One index case was identified at Oregon Health & Science University. Further cases were identified by a web-based survey of members of the American Uveitis Society, the International Uveitis Study Group, the Proctor Foundation mailing list server, and the First SUN International Workshop. Respondents were asked to provide clinical information about uveitis phenotype, AIH features, and treatment. Clinical information was obtained for seven in iduals (four females and three males age range, seven to 67 years) who suffered from AIH and uveitis. Average duration of follow-up was 5.5 years. All patients had chronic, persistent bilateral uveitis that was anterior (n = 3), intermediate (n = 1), or pan (n = 3) in location. Every patient had complications arising from his or her uveitis, including cataract (n = 5), glaucoma (n = 3), cystoid macular edema (n = 3), and posterior synechiae (n = 3). Final visual acuities ranged from 20/16 to hand movements. To treat the uveitis and/or AIH, the majority of patients required oral prednisone and all seven patients were treated with systemic immunosuppression. Despite the small size of this study, our findings suggest an association between AIH and uveitis. The uveitis is chronic, bilateral, and associated with sight-threatening complications, necessitating systemic immunosuppression in some in iduals.
Publisher: BMJ
Date: 08-11-2018
DOI: 10.1136/BJOPHTHALMOL-2018-312292
Abstract: To assess prevalence and causes of vision loss in Central and South Asia. A systematic review of medical literature assessed the prevalence of blindness (presenting visual acuity /60 in the better eye), moderate and severe vision impairment (MSVI presenting visual acuity /18 but ≥3/60) and mild vision impairment (MVI presenting visual acuity /12 and ≥6/18) in Central and South Asia for 1990, 2010, 2015 and 2020. In Central and South Asia combined, age-standardised prevalences of blindness, MSVI and MVI in 2015 were for men and women aged 50+years, 3.72% (80% uncertainty interval (UI): 1.39–6.75) and 4.00% (80% UI: 1.41–7.39), 16.33% (80% UI: 8.55–25.47) and 17.65% (80% UI: 9.00–27.62), 11.70% (80% UI: 4.70–20.32) and 12.25% (80% UI:4.86–21.30), respectively, with a significant decrease in the study period for both gender. In South Asia in 2015, 11.76 million in iduals (32.65% of the global blindness figure) were blind and 61.19 million in iduals (28.3% of the global total) had MSVI. From 1990 to 2015, cataract (accounting for 36.58% of all cases with blindness in 2015) was the most common cause of blindness, followed by undercorrected refractive error (36.43%), glaucoma (5.81%), age-related macular degeneration (2.44%), corneal diseases (2.43%), diabetic retinopathy (0.16%) and trachoma (0.04%). For MSVI in South Asia 2015, most common causes were undercorrected refractive error (accounting for 66.39% of all cases with MSVI), followed by cataract (23.62%), age-related macular degeneration (1.31%) and glaucoma (1.09%). One-third of the global blind resided in South Asia in 2015, although the age-standardised prevalence of blindness and MSVI decreased significantly between 1990 and 2015.
Location: United States of America
No related grants have been discovered for John Kempen.