Matthew B. Schlenker

Comparing a traditional single optotype visual acuity test with a computer-based visual acuity test for childhood amblyopia vision screening: a pilot study

OBJECTIVE To investigate the effectiveness of a traditional flip-chart optotype test, the Sheridan Gardiner test (SGT), in measuring visual acuity and detecting amblyopia, compared with a free, computer-based test (CBT), LazyeyeTest.org. DESIGN Prospective, masked, cross-over study. PARTICIPANTS Seventy kindergarten-aged children from a downtown Toronto elementary school enrolled in the Kids2See vision screening program. METHODS Visual acuity in the children was measured monocularly using both tests. The visual acuity results, number of referrals, and outcomes of referrals were compared, as was the usability from the perspective of the child and the vision screener. RESULTS The children were more likely to score low visual acuity values with the CBT, a result predicted by the existence of crowding bars on the CBTs optotypes. The CBT referred an extra 5 children than the SGT, and of the 4 who saw an ophthalmologist 2 had amblyopia. The SGT referred one child not referred by the CBT. The Cohens kappa coefficient was 0.67 and the difference in referral rates was not significant (p = 0.13). Relative to the SGT, the sensitivity of the CBT was 88%, specificity was 92%, positive predictive value was 58%, and negative predictive value was 98%. The CBT appeared to be easier and more efficient to administer, more stimulating, and was preferred by the children. CONCLUSIONS Replacing the SGT with LazyeyeTest.org would increase the efficiency and likely the sensitivity of amblyopia screening. Further research is warranted to confirm the outcomes and to determine if the CBT can be administered accurately by lay screeners.

Growth of medical and surgical vitreoretinal subspecialization in Ontario over 12 years

OBJECTIVE The past decade has seen significant paradigm shifts in the management of many retinal diseases. The goal of this study is to assess the effect these advances have had on the number of retinal specialists, and the differences in output between medical and surgical specialists at the population level. DESIGN Population-based analysis of surgical and medical retina therapeutic and diagnostic procedures among all ophthalmologists in Ontario, Canada, from April 1999 to March 2012. PARTICIPANTS This study included all ophthalmologists with an Ontario license and receiving remuneration from the Ontario Health Insurance Plan (OHIP). Ophthalmologists were categorized as a surgical or medical retina specialist based on the type and volume of retina-specific procedures performed each year. METHODS The IntelliHealth database operated by the Ministry of Health and Long Term Care was used to obtain anonymized physician services, which has excellent accuracy for procedure performance. RESULTS The number of retina specialists grew from 9.7% to 14.4% of the ophthalmology workforce. The proportion of late-career retina specialists (>25 years since graduation) doubled but had no influence on procedure output. Almost all retina specialists (90%) practice in the region they graduated medical school, and most (65%) practice in counties with a population greater than 400,000 people. Over the study period, the mean number of photocoagulation and fluorescein angiography performed was significantly higher among surgical retina specialists. Scleral buckling declined by 55% over the study period, whereas the number of pars plana vitrectomies grew by 49%. CONCLUSIONS The retina subspecialty is a growing area of ophthalmology and is mainly located in urban centres. There has been a dramatic shift in the types of procedures performed to treat medical and surgical diseases over the past decade. To our knowledge, this is the first study to quantify differences in diagnostic and procedure performance between the medical and surgical retina subspecialties.

Understanding macular holes that develop after repair of retinal detachment

OBJECTIVE To present the characteristics and outcomes of macular holes (MHs) that arise in eyes that have been treated for retinal detachment (RD). DESIGN Retrospective, interventional, consecutive case series. PARTICIPANTS We studied 18 eyes that developed a MH following RD repair. METHODS We report the demographic and clinical characteristics, MH closure rates, and best corrected visual acuity (BCVA) following MH repair. RESULTS We detected 18 full-thickness MHs in 985 eyes. In 14 of 18, the original RD involved the macula, and in 16 of 18, the BCVA was 20/200 or worse. Of the RDs, 8 of 18 required multiple procedures to achieve reattachment. Post-RD BCVA was 20/200 or worse in 15 of 18 patients. The median time to MH diagnosis after RD repair was 1 month (range, 2 days to 53 months), and from MH diagnosis to MH repair, the median time was 1.75 months (range, 3 weeks to 8 months). Of 16 eyes (89%) that underwent surgical repair of the MH, 14 achieved MH closure, 1 requiring multiple pars plana vitrectomy, and 11 saw at least 1 Snellen line of improvement (median, 1; range, 1 to 6); 2 lost vision (1 and 2 Snellen lines, respectively); and 3 remained unchanged at a median follow-up of 3 months (range, 1 month to 25 months). Of the 18 patients, 6 had at least 20/80 BCVA at last follow-up. CONCLUSIONS MHs following RDs (incidence 1.9%) are likely to be macula-off RDs requiring multiple interventions for RD repair. Post-MH-repair closure rates are similar to the rates for idiopathic MHs. BCVA outcomes are moderate and are dependent on impairment post-RD repair. The findings suggest other pathogenic mechanisms besides vitreofoveal traction may be leading to these MHs.

Research productivity of Canadian ophthalmology departments in top 10 ophthalmology and vision science journals from 2001 to 2010

OBJECTIVE To evaluate the research productivity of Canadian ophthalmology departments in terms of research volume, impact, funding, and cost-efficiency, and compare these measures with the top 6 U.S. departments. DESIGN Systemic review. METHODS Using the Web of Science, we obtained the number of peer-reviewed research articles and citations in which an author listed an ophthalmology department (or affiliated university or hospital) from 2001 to 2010 in the top 10 ophthalmology and vision sciences journals, as well as the Canadian Journal of Ophthalmology. Federal research funding received from the Canadian Institutes of Health Research and National Institutes of Health was also obtained. RESULTS The 3 universities that produced the highest number of articles were the University of Toronto (UofT), McGill University, and the University of British Columbia (UBC). UofT also produced the largest number of citations, followed by UBC and Dalhousie University. For the number of citations per article, the top 3 were the University of Ottawa, Dalhousie University, and the University of Calgary. McGill University, the University of Montreal, and UofT received the most federal funding. The 3 Canadian universities with the lowest funding (cost) per article were UofT, UBC, and McMaster University. The top contributors to the Canadian Journal of Ophthalmology from 2001 to 2010 were UofT, the University of Ottawa, and McGill University. CONCLUSIONS Larger Canadian departments tended to generate higher research volume and obtained more federal funding, but smaller departments also contributed significantly, and sometimes surpassed larger departments, in terms of research impact and cost-efficiency. The top 6 U.S. departments generated higher research volume and received more federal research funding than their Canadian counterparts. However, when research impact and cost-efficiency were examined, Canadian departments performed similar to the top U.S. departments.

Risk of bias assessment of randomised controlled trials in high-impact ophthalmology journals and general medical journals: a systematic review

Evidence-based treatments in ophthalmology are often based on the results of randomised controlled trials. Biased conclusions from randomised controlled trials may lead to inappropriate management recommendations. This systematic review investigates the prevalence of bias risk in randomised controlled trials published in high-impact ophthalmology journals and ophthalmology trials from general medical journals. Using Ovid MEDLINE, randomised controlled trials in the top 10 high-impact ophthalmology journals in 2015 were systematically identified and critically appraised for the prevalence of bias risk. Included randomised controlled trials were assessed in all domains of bias as defined by the Cochrane Collaboration. In addition, the prevalence of conflict of interest and industry sponsorship was investigated. A comparison with ophthalmology articles from high-impact general medical journals was performed. Of the 259 records that were screened from ophthalmology-specific journals, 119 trials met all inclusion criteria and were critically appraised. In total, 29.4% of domains had an unclear risk, 13.8% had a high risk and 56.8% had a low risk of bias. In comparison, ophthalmology articles from general medical journals had a lower prevalence of unclear risk (17.1%), higher prevalence of high risk (21.9%) and a higher prevalence of low risk domains (61.9%). Furthermore, 64.7% of critically appraised trials from ophthalmology-specific journals did not report any conflicts of interest, while 70.6% did not report an industry sponsor of their trial. In closing, it is essential that authors, peer reviewers and readers closely follow published risk of bias guidelines.

Association of Cataract Surgery With Traffic Crashes

Importance Cataracts are the most common cause of impaired vision worldwide and may increase a driver’s risk of a serious traffic crash. The potential benefits of cataract surgery for reducing a patient’s subsequent risk of traffic crash are uncertain. Objective To conduct a comprehensive longitudinal analysis testing whether cataract surgery is associated with a reduction in serious traffic crashes where the patient was the driver. Design, Setting, and Participants Population-based individual-patient self-matching exposure-crossover design in Ontario, Canada, between April 1, 2006, and March 31, 2016. Consecutive patients 65 years and older undergoing cataract surgery (n = 559 546). Interventions First eye cataract extraction surgery (most patients received second eye soon after). Main Outcomes and Measures Emergency department visit for a traffic crash as a driver. Results Of the 559 546 patients, mean (SD) age was 76 (6) years, 58% were women (n = 326 065), and 86% lived in a city (n = 481 847). A total of 4680 traffic crashes (2.36 per 1000 patient-years) accrued during the 3.5-year baseline interval and 1200 traffic crashes (2.14 per 1000 patient-years) during the 1-year subsequent interval, representing 0.22 fewer crashes per 1000 patient-years following cataract surgery (odds ratio [OR], 0.91; 95% CI, 0.84-0.97; P = .004). The relative reduction included patients with diverse characteristics. No significant reduction was observed in other outcomes, such as traffic crashes where the patient was a passenger (OR, 1.03; 95% CI, 0.96-1.12) or pedestrian (OR, 1.02; 95% CI, 0.88-1.17), nor in other unrelated serious medical emergencies. Patients with younger age (OR, 1.27; 95% CI, 1.13-1.14), male sex (OR, 1.64; 95% CI, 1.46-1.85), a history of crash (baseline OR, 2.79; 95% CI, 1.94-4.02; induction OR, 4.26; 95% CI, 2.01-9.03), more emergency visits (OR, 1.34; 95% CI, 1.19-1.52), and frequent outpatient physician visits (OR, 1.17; 95% CI, 1.01-1.36) had higher risk of subsequent traffic crashes (multivariable model). Conclusions and Relevance This study suggests that cataract surgery is associated with a modest decrease in a patient’s subsequent risk of a serious traffic crash as a driver, which has potential implications for mortality, morbidity, and costs to society.

Cyclodialysis cleft repair: a multi-centered, retrospective case series: Cyclodialysis cleft repair case series

There is a paucity of evidence analysing the treatment of cyclodialysis clefts.

Cyclodialysis cleft repair: a multi-centered, retrospective case series - response

No abstract is available for this article. This article is protected by copyright. All rights reserved.

Gold Metal Shunt (GMS) Implant

Surgical management of uncontrolled glaucoma poses several challenges to the ophthalmologist. Suprachoroidal procedures obviate the need to utilize conjunctiva to create filtering blebs (i.e., trabeculectomies) and reduce the risk of failure of bleb-related surgery secondary to bleb-related fibrosis, scarring, infection, or overfiltration. The gold metal shunt implant takes advantage of the natural negative pressure gradient from the anterior chamber into the suprachoroidal space while still providing natural counterpressure to prevent hypotony.

Cataract Extraction with Gold Metal Shunt (GMS) Implant

Surgical management of cataract patients with uncontrolled glaucoma poses several challenges to the ophthalmologist. With the goal of improving visual acuity and optimizing intraocular pressure, the ophthalmologist may choose to combine cataract extraction with glaucoma surgery in one operative encounter. Suprachoroidal procedures obviate the need to utilize the conjunctiva to create filtering blebs (i.e., trabeculectomies) and reduce the risk of failure of bleb-related surgery secondary to bleb-related fibrosis, scarring, infection, or overfiltration. The gold metal shunt implant takes advantage of the natural negative pressure gradient from the anterior chamber into the suprachoroidal space, while still providing natural counterpressure to prevent hypotony.