Using Fused Data from Perimetry and Optical Coherence Tomography to Improve the Detection of Visual Field Progression in Glaucoma.

Perimetry and optical coherence tomography (OCT) are both used to monitor glaucoma progression. However, combining these modalities can be a challenge due to differences in data types. To overcome this, we have developed an autoencoder data fusion (AEDF) model to learn compact encoding (AE-fused data) from both perimetry and OCT. The AEDF model, optimized specifically for visual field (VF) progression detection, incorporates an encoding loss to ensure the interpretation of the AE-fused data is similar to VF data while capturing key features from OCT measurements. For model training and evaluation, our study included 2504 longitudinal VF and OCT tests from 140 glaucoma patients. VF progression was determined from linear regression slopes of longitudinal mean deviations. Progression detection with AE-fused data was compared to VF-only data (standard clinical method) as well as data from a Bayesian linear regression (BLR) model. In the initial 2-year follow-up period, AE-fused data achieved a detection F1 score of 0.60 (95% CI: 0.57 to 0.62), significantly outperforming (p < 0.001) the clinical method (0.45, 95% CI: 0.43 to 0.47) and the BLR model (0.48, 95% CI: 0.45 to 0.51). The capacity of the AEDF model to generate clinically interpretable fused data that improves VF progression detection makes it a promising data integration tool in glaucoma management.

Prevalence of self-reported visual impairment among people in Canada with and without diabetes: findings from population-based surveys from 1994 to 2014.

BACKGROUND: Diabetes, a leading cause of visual impairment, is on the rise in Canada. We assessed trends in the prevalence of visual impairment among people in Canada with and without diabetes to inform the development of strategies and policies for the management of visual impairment. METHODS: We analyzed self-reported data from respondents aged 45 years and older in 7 cycles of nationwide surveys (National Population Health Survey and Canadian Community Health Survey) from 1994/95 to 2013/14. The age- and sex-standardized prevalence of visual impairment was calculated. We assessed comparisons by levels of education and income, using sex-standardized prevalence owing to sparse data. RESULTS: Among people in Canada with diabetes, the age- and sex-standardized prevalence of visual impairment was 7.37% (95% confidence interval [CI] 5.31%-9.43%) in 1994/95 and 1996/97 combined, decreasing to 3.03% (95% CI 2.48%-3.57%) in 2013/14, giving a standardized prevalence ratio of 0.41 (95% CI 0.30-0.56) comparing 2013/14 with 1994/95 and 1996/97 combined. Among people in Canada without diabetes, visual impairment prevalence decreased from 3.72% (95% CI 3.31%-4.14%) in 1994/95 and 1996/97 combined to 1.69% (95% CI 1.52%-1.87%) in 2013/14, with a standardized prevalence ratio of 0.45 (95% CI 0.40-0.52). Decreased sex-standardized prevalence of visual impairment was observed among people with high and low education levels and incomes among those with and without diabetes. INTERPRETATION: Visual impairment prevalence was roughly 2 times higher among those with versus without diabetes in all survey years; from 1994 to 2014, visual impairment prevalence decreased among those with and without diabetes irrespective of education and income levels. These results suggest effective collective efforts by clinicians, researchers, the public and government.

Atypical responses to faces during binocular rivalry in early glaucoma.

Purpose: Glaucoma is a progressive optic neuropathy that damages retinal ganglion cells and a neurodegenerative disease as it affects neural structures throughout the brain. In this study, we examined binocular rivalry responses in patients with early glaucoma in order to probe the function of stimulus-specific cortical areas involved in face perception. Methods: Participants included 14 individuals (10 females, mean age 65 ± 7 years) with early pre-perimetric glaucoma and 14 age-matched healthy controls (7 females, mean age 59 ± 11 years). The 2 groups were equivalent in visual acuity and stereo-acuity. Three binocular rivalry stimulus pairs were used: (1) real face/house, (2) synthetic face/noise patch, and (3) synthetic face/spiral. For each stimulus pair, the images were matched in size and contrast level; they were viewed dichotically, and presented centrally and eccentrically at 3 degrees in the right (RH) and in the left hemifield (LH), respectively. The outcome measures were rivalry rate (i.e., perceptual switches/min) and time of exclusive dominance of each stimulus. Results: For the face/house stimulus pair, rivalry rate of the glaucoma group (11 ± 6 switches/min) was significantly lower than that of the control group (15 ± 5 switches/min), but only in the LH location. The face dominated longer than the house in the LH for both groups. Likewise, for the synthetic face/noise patch stimulus pair, rivalry rate of the glaucoma group (11 ± 6 switches/min) was lower than that of the control group (16 ± 7 switches/min) in the LH, but the difference failed to reach significance. Interestingly, the mixed percept dominated less in glaucoma than in the control group. For the synthetic face/spiral stimulus pair, the glaucoma group had lower rivalry rate at all 3 stimulus locations. Conclusion: This study reveals atypical responses to faces during binocular rivalry in patients with early glaucoma. The results may be suggestive of early neurodegeneration affecting stimulus-specific neural structures involved in face processing starting in the pre-perimetric phase of the disease.

A Data-Driven Model for Simulating Longitudinal Visual Field Tests in Glaucoma.

Purpose: To develop a simulation model for glaucomatous longitudinal visual field (VF) tests with controlled progression rates. Methods: Longitudinal VF tests of 1008 eyes from 755 patients with glaucoma were used to learn the statistical characteristics of VF progression. The learned statistics and known anatomic correlations between VF test points were used to automatically generate progression patterns for baseline fields of patients with glaucoma. VF sequences were constructed by adding spatially correlated noise templates to the generated progression patterns. The two one-sided test (TOST) procedure was used to analyze the equivalence between simulated data and data from patients with glaucoma. VF progression detection rates in the simulated VF data were compared to those in patients with glaucoma using mean deviation (MD), cluster, and pointwise trend analysis. Results: VF indices (MD, pattern standard deviation), MD linear regression slopes, and progression detection rates for the simulated and patients' data were practically equivalent (TOST P < 0.01). In patients with glaucoma, the detection rates in 7 years using MD, cluster, and pointwise trend analysis were 24.4%, 26.2%, and 38.4%, respectively. In the simulated data, the mean detection rates (95% confidence interval) for MD, cluster, and pointwise trend analysis were 24.7% (24.1%-25.2%), 24.9% (24.2%-25.5%), and 35.7% (34.9%-36.5%), respectively. Conclusions: A novel simulation model generates glaucomatous VF sequences that are practically equivalent to longitudinal VFs from patients with glaucoma. Translational Relevance: Simulated VF sequences with controlled progression rates can support the evaluation and optimization of methods to detect VF progression and can provide guidance for the interpretation of longitudinal VFs.

Updated inventory and projections for Canada's ophthalmology workforce.

OBJECTIVE: To update Canadian ophthalmology workforce data and provide future predictions. DESIGN: Cross-sectional study. PARTICIPANTS: Ophthalmologists working in Canada from 1968 to 2019. METHODS: Supply and demographics of physicians in Canada were obtained from the Canadian Institute for Health Information. Physician training numbers were obtained from the Canadian Post-MD Education Registry. Using Statistic Canada population projections, future predictions about Canada's ophthalmology workforce were determined. RESULTS: In 2020, there were 1323 ophthalmologists in Canada; 27.3% were female and 20.9% were aged ≥65 years. Overall, there were 3.48 ophthalmologists per 100,000 population. Provincial distributions varied from 2.32 in Manitoba to 5.00 in Nova Scotia. For the population aged ≥65 years, there were 19.35 ophthalmologists per 100,000 population. If the yearly change in ophthalmologists' numbers remains as during the past 10 years, the number of ophthalmologists per 100,000 population is predicted to be slightly reduced to 3.21 in 2068 in a high-growth scenario and increased to 4.08 and 5.08 in a medium- and low-growth scenario, respectively. For the population aged ≥65 years, corresponding predicted ratios are 14.00 in a high-growth scenario, 17.72 in a medium-growth scenario, and 18.40 in a low-growth scenario. CONCLUSIONS: The ratio of ophthalmologists to population aged ≥65 years, the predominant cohort treated by ophthalmologists, is projected to drop by 4.9% and 27.7% in the low- and high-growth scenarios, respectively, potentially creating a challenge to vision care delivery. A small increase in ophthalmology residency positions could protect against this.

Backlog in ophthalmic surgeries associated with the COVID-19 pandemic in Ontario 2020.

OBJECTIVE: To assess the volume of deferred ophthalmic surgeries in Ontario associated with the COVID-19 pandemic from March to December 2020 and suggest strategies and time required to clear the backlog. DESIGN: Cross-sectional study. PARTICIPANTS: Ontarians eligible for the Ontario Health Insurance Plan in 2017-2020. METHODS: Backlog and clearance time for ophthalmic surgeries associated with the COVID-19 pandemic were estimated from time-series forecasting models and queuing theory. RESULTS: From March 16 to December 31, 2020, the estimated ophthalmic surgical backlog needing operating rooms was 92,150 surgeries (95% prediction interval, 71,288-112,841). Roughly 90% of the delayed surgeries were cataract surgeries, and a concerning 4% were retinal detachment surgeries. Nearly half the provincial backlog (48%; 44,542 of 92,150) was in patients from the western health region. In addition, an estimated 23,755 (95% prediction interval, 14,656-32,497) anti-vascular endothelial growth factor injections were missed. Estimated provincial clearance time was 248 weeks (95% CI, 235-260) and 128 weeks (95% CI, 121-134) if 10% and 20% of operating room surgical capacity per week were added, respectively, based on the weekly ophthalmic surgical volume in 2019. CONCLUSIONS: Ontario data demonstrate that the magnitude of the ophthalmic surgical backlog in 2020 alone raises serious concerns for meeting the ophthalmic surgical needs of patients. As the pandemic continues, the accrued backlog size is likely to increase. Planning and actions are needed urgently to better manage the collateral impacts of the pandemic on the ophthalmic surgical backlog.

Binocular Summation of Visual Acuity at High and Low Contrast in Early Glaucoma.

PRCIS: This study examined the integrity of binocular summation function in patients with mild glaucoma. We found that binocular summation of visual acuity is preserved in these patients, despite their reduced monocular inputs. PURPOSE: Binocular summation represents superiority of binocular to monocular performance. In this study we examined the integrity of binocular summation function in patients with early glaucoma who had structural glaucomatous changes but otherwise had no significant interocular acuity asymmetry or other functional deficit detected with standard clinical measures. MATERIALS AND METHODS: Participants included 48 patients with early glaucoma according to Hodapp, Anderson, and Parrish 2 (HAP2) criteria (age 65±12 y) and 42 healthy controls (age 60±12 y), matched for stereoacuity. Visual acuity was assessed binocularly and monocularly at high (95%) and low (25%) contrast using the Early Treatment Diabetic Retinopathy Study (ETDRS) charts at 6 m. Binocular acuity summation was evaluated utilizing a binocular ratio (BR). RESULTS: Overall, binocular and monocular visual acuity of the control group was better than that of the glaucoma group for both contrast levels, P =0.001. For the glaucoma group, there was a significant difference between BRs at high and low contrast, 0.01±0.05 and 0.04±0.06 ( P =0.003), respectively. For the control group, the difference between BR at high and low contrast was not statistically significant, 0.00±0.07 and 0.02±0.06 ( P =0.25), respectively. CONCLUSION: For patients with early glaucoma, binocular summation function for visual acuity was preserved at both contrast levels. This suggests an adaptation of the visual system in early stages of glaucoma that allows for normal binocular summation in the presence of reduced monocular visual input.

Use of virtual care in ophthalmology in Ontario, Canada in 2020 during the COVID-19 pandemic.

OBJECTIVE: To investigate the use and trends of virtual care in ophthalmology and examine associated factors in a universal health care system during the COVID-19 pandemic in 2020. DESIGN: Cross-sectional study. PARTICIPANTS: Ontarians eligible for the Ontario Health Insurance Plan. METHODS: We used physician billing data from 2017-2020 to describe the use of virtual versus in-person care. We used logistic regression to examine factors associated with virtual care use. RESULTS: The uptake of ophthalmic virtual visits increased immediately following the government's directive to ramp down clinic activities and institution of a new virtual fee code (17.6%), peaked 2 weeks later (55.8%), and decreased immediately after the directive was lifted (24.2%). In March-December 2020, virtual visits were higher in female (11.6%) versus male (10.3%) patients and in patients <20 years of age (16.4%) and 20-39 years of age (12.3%) versus those aged 40-64 years (10.8%) and 65+ years (10.6%). Patients residing in the poorest/poorer neighbourhoods (10.9%) had similar use as their counterparts (11.1%). Patients with an acute infectious disease (14.2%) or nonurgent diagnosis (16.2%) had the highest use. Those with retinal disease had the lowest use (4.2%). Female ophthalmologists (15.4%) provided virtual care more often than male ophthalmologists (9.9%). Ophthalmologists aged 60-69 years (13.1%) provided virtual care more often than any other age groups (<40 years: 11.3%; 40-49 years: 11.0%; 50-59 years: 10.0%; and 70+ years: 7.7%). Multiple logistic regression models revealed similar results. CONCLUSION: Virtual care in ophthalmology increased significantly during the initial phase of the pandemic and decreased thereafter. There were significant variations in virtual care use by patient and ophthalmologist characteristics.

Differences in Practice Patterns and Payments for Female and Male Dermatologists: A Canadian Population-Based Study Over 3 Decades.

BACKGROUND: Canada's fee-for-service physician reimbursement system, where a set rate is provided for each service, suggests that a physician sex pay gap should not exist. However, recent evidence has questioned this presumption. OBJECTIVES: To characterize trends in demographics and billing, overall and by sex, for dermatologists compared to other medical and surgical specialty groups in Ontario, Canada. METHODS: Using population-based data, analysis of physician billing and clinical activity from Ontario, Canada, over 27 years (1992-2018) was performed. Multilevel regression models were used to examine unadjusted and adjusted differences in payments between females and males over time, while controlling for age, distinct patients seen, patient visits, and full-time equivalent. RESULTS: A total of 22 389 physicians were included in the analyses, including 381 dermatologists. The proportion of female dermatologists increased from 32% in 1992 to 46% in 2018. Dermatologists' median Ontario Health Insurance Plan (OHIP) payments were $415 340 (IQR: 285 630-566 580) in 1992 compared to $296 750 (IQR: 164 480-493 180) in 2018. Male dermatologists' OHIP payments were 20% more than their female counterparts across the entire study period. After adjusting for practice volumes, there was no significant pay gap amongst female and male dermatologists (P = .42); however, the sex pay gap remained significant for the other specialty groups (P < .001). From 1992 to 2018, dermatologists on average saw 19% fewer distinct patients per year and 15% fewer visits per patient. CONCLUSIONS: The overall sex pay gap within medical dermatology can be attributed to differences in practice patterns, whereas the sex pay gap remained significant in the other specialty groups.

Effect of Prophylactic Aqueous Suppression on Ahmed Glaucoma Valve Surgery Success.

Purpose: To evaluate the effect of prophylactic aqueous suppressants immediately post-Ahmed glaucoma valve (AGV) surgery on the rate of hypertensive phase and success. Methods: Retrospective case-control study of 80 eyes with refractory glaucoma undergoing AGV surgery. Forty eyes in the intervention group (preoperative aqueous suppressants continued postoperatively) and 40 in the control group (all glaucoma drops stopped after surgery and reintroduced as required) were included in this study. Patients were followed for 1 year. Data collected included intraocular pressure (IOP), number of glaucoma medications, and number of eyes requiring further IOP lowering surgery. The frequency of hypertensive phase and 1-year success was compared between the groups. Results: Hypertensive phase occurred in 22.5% of the intervention group compared to 42.5% of the control group; however, this difference was not statistically significant (P = 0.06). Success at 1 year (IOP ≤21 mmHg but ≥5 mmHg and 20% reduction from baseline without additional surgery) was similar in each group: 77.5% in the intervention group and 62.5% in the control group (P = 0.22). However, at 1 year, significantly more eyes in the intervention group had an IOP ≤17 mmHg (95% vs. 80%, P = 0.04). The mean time interval to a second IOP lowering procedure was significantly shorter in the control group (P < 0.005). Conclusions: With prophylactic preoperative aqueous suppressants, more eyes achieved an IOP of ≤17 mmHg. The time interval to repeat the glaucoma procedure was significantly shorter in the control group.

Perceptual Grouping During Binocular Rivalry in Mild Glaucoma.

Purpose: This study tested perceptual grouping during binocular rivalry to probe the strength of neural connectivity of the visual cortex involved in early visual processing in patients with mild glaucoma. Methods: Seventeen patients with mild glaucoma with no significant visual field defects and 14 healthy controls participated. Rivalry stimuli were 1.8°-diameter discs, containing horizontal or vertical sine-wave gratings, viewed dichoptically. To test the grouping, two spatially separated identical stimuli were presented eccentrically to the same or different eyes and to the same or different hemifields. The outcome measures were the time of exclusive dominance of the grouped percept (i.e., percept with synchronized orientations), the rivalry rate, and the epochs of exclusive dominance. Results: For both groups, the grouping occurred primarily for the matching orientations in the same eye/same hemifield (MO SE/SH) and for the matching orientations in the same eye/different hemifield (MO SE/DH) conditions. Time dominance of the grouped percept of the glaucoma group was similar to that of the control group in all conditions. The rivalry rates in the MO SE/SH and MO SE/DH conditions were significantly larger in the control group than in the glaucoma group. The epochs of exclusive dominance of the grouped percept in the MO SE/SH condition were a median of 48-ms longer for the control group, but a median of 116-ms shorter for the glaucoma group when compared to those in the MO SE/DH condition. Conclusion: Patients with mild glaucoma show clear impairments in binocular rivalry while evidence for deficits in perceptual grouping could be inferred only indirectly. If these deficits truly exist, they may have implications for higher levels of visual processing, such as object recognition and scene segmentation, but these predictions remain to be tested in future studies.

Differences by sex in supply, payments and clinical activity of family physicians in Ontario: a retrospective population-based cohort study.

BACKGROUND: The proportion of women entering medicine has increased in recent years, and understanding the different practice patterns of female and male family physicians (FPs) will provide important information for health workforce planning. We sought to evaluate differences by sex in the supply, payments and clinical activity among FPs in Ontario. METHODS: We conducted a cohort study using claims data from the Ontario Health Insurance Plan. We included all Ontario FPs who submitted claims from 1992 to 2018. We analyzed data using regression analyses for our outcomes of yearly number of FPs, payments, patient visits and distinct patients. RESULTS: The number of practising FPs increased from 10 370 in 1992 to 14 329 in 2018, with an annual increase of 155 female FPs and 13 male FPs. In 2018, male FPs outnumbered female FPs by 1159. Among male FPs, 32.7% worked less than 1 full-time equivalent (FTE) position, 18.1% worked 1 FTE and 49.2% worked more than 1 FTE, with little change over the 27-year study period. Among female FPs, the percentage of those who worked less than 1 FTE position decreased over time (58.6% in 1998 to 48.3% in 2015), those who worked 1 FTE was stable (22.2%-24.3%) and those who worked more than 1 FTE increased (18.7% in 1998 to 28.0% in 2017). Yearly payments were higher for male FPs than female FPs by 40%-60% overall and by 10%-20% in FPs who worked more than 1 FTE. For FPs who worked 1 FTE or less than 1 FTE, both sexes had similar payment amounts (from 2005-2018). For FPs who worked 1 FTE, female FPs were less likely to receive payments from fee-for-service after 2004, and had 550 fewer visits and 121 fewer patients annually than male FPs. INTERPRETATION: In Ontario, there are differences by sex in FP supply, payments, percentages of FTE groups, number of patient visits and number of distinct patients. Health administrators should be mindful of these differences when considering FP workforce plans to ensure a stronger primary health care system, with adequate health care delivery for the population.

Trends in payments among male and female ophthalmologists in Ontario from 1992 to 2018.

OBJECTIVE: To examine sex differences in Ontario Health Insurance Plan (OHIP) payments from 1992 to 2018. DESIGN: Population-based observational study. PARTICIPANTS: Ophthalmologists submitting claims to OHIP from 1992 to 2018. METHODS: Physician billing data over 27 years (1992-2018) were analyzed for yearly number of ophthalmologists, OHIP payments, distinct patients, and patient visits. RESULTS: Yearly median OHIP payments to female ophthalmologists were less than to male ophthalmologists with a gap ratio of 0.55 in 1992 to 0.73 in 2018. Stratifying by full-time equivalent (FTE), there was little difference in median payments between males and females for 1 FTE. Median female-to-male payments ratio varied from 0.80 to 1.16 for <1 FTE and 1.14 to 0.84 for >1 FTE from 1992 to 2018. Among female ophthalmologists, 72.7% and 52.9% were <1 FTE and 11.4% and 19.2% were >1 FTE in 1992 and 2018, respectively. In comparison, for male ophthalmologists, 35.7% and 45.6% were <1 FTE and 43.4% and 45.6% were >1 FTE in 1992 and 2018, respectively. Overall, male ophthalmologists had more patients and patient visits than female ophthalmologists, but there was little difference between male and female ophthalmologists for 1 and >1 FTE. The results for <1 FTE varied by year. CONCLUSIONS: Overall, female ophthalmologists have lower OHIP payments compared with males, but there was little difference for those stratified to 1 FTE. This overall payments difference by sex is largely explained by the higher proportion of <1 FTE females, lower proportion of >1 FTE females, and higher payments for >1 FTE males.

Impact of discontinuing government-funded routine eye exams on new glaucoma diagnoses in Ontario.

OBJECTIVE: In 2004, government-funded routine eye exams were discontinued for individuals aged 20-64 years in Ontario. We assessed whether this policy change reduced the rate of new glaucoma diagnoses. DESIGN: Cohort-based time-series analysis. PARTICIPANTS: Ontarians aged 20+ years in 2000-2014. METHODS: Province-wide physician billing data were analyzed using segmented regression analysis. New glaucoma diagnoses were defined as the first glaucoma diagnostic billing code submitted by an ophthalmologist or optometrist among Ontarians who did not visit an ophthalmologist or an optometrist in the year prior to the study year. RESULTS: Post- versus pre-2004, the rate of new glaucoma billings was reduced in all age groups: -2.7‰ (p < 0.0001) in the age group 20-39 years, -8.2‰ (p < 0.0001) in the age group 40-64 years (p < 0.0001), and -2.1‰ (p = 0.0003) in the age group 65+ years. This corresponds to a decreased number of individuals with a new glaucoma billing after 2004 versus before 2004: -8,800 (p < 0.001) in the age group 20-39 years, -32,234 (p < 0.0001) in the age group 40-64 years, and -3,255 (p = 0.0012) in the age group 65+ years. Reduced rates of new glaucoma diagnostic billings were seen in males, females and rural and urban residents among policy-affected and policy-unaffected age groups. Ontarians living in the wealthiest neighbourhood areas also had a significantly reduced rate after versus before 2004: -2.7‰ (p < 0.0001) for the age group 20-39 years, -9.0‰ (p < 0.0001) for the age group 40-64 years, and -2.3‰ (p < 0.001) for the age group 65+ years. CONCLUSIONS: Discontinuation of government-funding for routine eye exams was associated with a significantly reduced rate of new glaucoma diagnostic billings irrespective of sociodemographics. More research is needed to understand the reduced glaucoma billings in unaffected seniors and those living in the wealthiest neighbourhood areas.

The Effect of Government-Uninsured Optometric Services on the Use of Primary Care Providers.

INTRODUCTION: Eye care in many countries is provided by optometrists, ophthalmologists, primary care providers (PCPs, including family physicians and pediatricians) and emergency department (ED) physicians. In the province of Prince Edward Island (PEI), Canada, optometric services are not government-insured, while services provided by other eye care providers are government-insured. Clinics of optometrists, PCPs and ED physicians are widely distributed across the island. Clinics of ophthalmologists however are concentrated in the capital city Charlottetown. PURPOSE: To investigate if more patients visited government-insured PCPs and EDs for eye care when local optometric services are government-uninsured and government-insured ophthalmologists are potentially distant. METHODS: From PEI physician billing database, we identified all patients with an ocular diagnosis from 2010-2012 using International Classification of Diseases, 9th Revision (ICD-9) codes. The utilization of government-insured PCPs and EDs in five geographical regions was assessed utilizing patients' residential postal code. Of the five regions, Prince was the region farthest from the capital Charlottetown. RESULTS: Compared to utilization of government-insured PCPs for ocular diagnoses in Charlottetown (13.5% in 2010, 95% confidence interval [CI] 12.9-14.0%), the utilization in Prince (22.4% in 2010, 95% CI 21.7-23.1%) was nearly double (p<0.05). The utilization of ED physicians for ocular diagnoses was similarly double in Prince (8.8%, 95% CI 8.3-9.3%) versus Charlottetown (4.1%, 95% CI 3.8-4.5%). The utilization of ophthalmologists however was significantly lower in Prince (43%, 95% CI 41.4-42.9%) versus Charlottetown (56.3%, 95% CI 55.6-57.1%). Similar trends remained throughout 2010-2012. CONCLUSION: When optometric services are government-uninsured and government-insured ophthalmologist services are geographically distant, ocular patients utilized PCPs and ED physicians more frequently. Due to different levels of training and available equipment for eye examinations among PCPs, ED physicians and optometrists, the quality of eye care and cost-effectiveness of increased use of PCPs and ED physicians for ocular management warrant further investigation. TRIAL REGISTRATION: Not applicable.

Frequency and source of prescription eyewear insurance coverage in Ontario: a repeated population-based cross-sectional study using survey data.

BACKGROUND: Insurance coverage may reduce cost barriers to obtain vision correction. Our aim was to determine the frequency and source of prescription eyewear insurance to understand how Canadians finance optical correction. METHODS: We conducted a repeated population-based cross-sectional study using 2003, 2005 and 2013-2014 Canadian Community Health Survey data from respondents aged 12 years or older from Ontario, Canada. In this group, the cost of prescription eyewear is not covered by the government unless one is registered with a social assistance program or belongs to a specific population. We determined the frequency and source of insurance coverage for prescription eyewear in proportions. We used survey weights provided by Statistics Canada in all analyses to account for sample selection, a complex survey, and adjustments for seasonal effect, poststratification, nonresponse and calibration. We compared unadjusted proportions and adjusted prevalence ratios (PRs) of having insurance. RESULTS: Insurance covered all or part of the costs of prescription eyewear for 62% of Ontarians in all 3 survey years. Of those insured, 84.1%-86.0% had employer-sponsored coverage, 9.0%-10.3% had government-sponsored coverage, and 5.7%-6.8% had private plans. Employer-sponsored coverage remained constant for those in households with postsecondary graduation but decreased significantly for those in households with less than secondary school graduation, from 67.0% (95% confidence interval [CI] 63.2%-70.8%) (n = 175 000) in 2005 to 54.6% (95% CI 50.1%-59.2%) (n = 123 500) in 2013-2014. Government-sponsored coverage increased significantly for those in households with less than secondary school graduation, from 29.2% (95% CI 25.5%-32.9%) (n = 76 400) in 2005 to 41.7% (95% CI 37.2%-46.1%) (n = 93 900) in 2013-2014. In 2013-2014, Ontarians in households with less than secondary school graduation were less likely than those with secondary school graduation to report employer-sponsored coverage (adjusted PR 0.79, 95% CI 0.75-0.84) but were more likely to have government-sponsored coverage (adjusted PR 1.27, 95% CI 1.06-1.53). INTERPRETATION: Sixty-two percent of Ontarians had prescription eyewear insurance in 2003, 2005 and 2013-2014; the largest source of insurance was employers, primarily covering those with higher education levels, whereas government-sponsored insurance increased significantly among those with lower education levels. Further research is needed to elucidate barriers to obtaining prescription eyewear and the degree to which affordability impairs access to vision correction.

Ophthalmology-focused publications and findings on COVID-19: A systematic review.

PURPOSE: To summarize COVID-19 research endeavors by ophthalmologists/researchers in terms of publication numbers, journals and author countries, and to detail key findings. METHODS: The LitCovid database was systematically reviewed for ophthalmology-focused COVID-19 articles. The quality of the evidence was assessed for articles investigating conjunctivitis in COVID-19 patients. RESULTS: There were 21,364 articles in LitCovid on June 12, 2020, of which 215 (1%) were ophthalmology-focused. Of articles on COVID-19 transmission, 3.3% were ophthalmology-focused. Ophthalmology-focused articles were published in 68 journals and originated from 25 countries. The top five countries publishing ophthalmology-focused articles (China, India, United States of America, Italy, and United Kingdom) produced 145/215 (67%) articles. A total of 16 case reports/series from eight countries reported that conjunctivitis can be the initial or the only symptom of COVID-19 infection. Conjunctivitis may occur in the middle phase of COVID-19 illness. A total of 10 hospital-based cross-sectional studies reported that between 0% and 31.6% of COVID-19 patients have conjunctivitis or other ocular conditions, with a pooled prevalence of 5.5% reported in a meta-analysis. Viral RNA was detected in conjunctival swabs of patients with and without ocular manifestations, after resolution of conjunctivitis, after nasopharyngeal swabs turned negative and in retina of deceased COVID-19 patients. CONCLUSION: Within 3 months of declaring the COVID-19 pandemic, 215 ophthalmology-focused articles were published in PubMed, concentrating on disease manifestations and transmission. The reported presence of conjunctivitis or other ocular conditions in COVID-19 patients is varied. Clinicians should be alert for ocular involvement in COVID-19 infections and possible ocular transmission even in patients without ocular symptoms.

Cost-related nonadherence with glaucoma medications in Ontario.

OBJECTIVE: To determine the proportion of glaucoma patients in Ontario aged 25-64 who lack insurance coverage for glaucoma medications and to assess the frequency of cost-related nonadherence to glaucoma medications. DESIGN: Cross-sectional study. PARTICIPANTS: Glaucoma patients on medication from 2 glaucoma clinics in Toronto, Ontario. METHODS: 100 consecutive glaucoma patients aged 25-64 (not entitled to provincial drug benefit) and 100 consecutive glaucoma patients aged 65+ (entitled to provincial drug benefit), all on topical glaucoma therapy, completed a standardized questionnaire. Questions included insurance coverage for glaucoma medications, cost concerns when paying for glaucoma medications, cost-related nonadherence, and sociodemographics. RESULTS: 25.8% of those aged 25-64 express concerns about the cost of their glaucoma medications compared to 7.1% of those aged 65+ (p < 0.001). Patients aged 25-64 were also significantly more likely to report at least one form of cost-related nonadherence (15.5% vs 2.0%, p = 0.001) and significantly more likely to report missing eye drops in a given week than patients aged 65+ (32.0% vs 16.7%, p = 0.01). 17% (95% confidence interval 11%-26%) of patients aged 25-64 self-reported having no insurance coverage for their glaucoma medications. Of those with coverage, the most common source of insurance was employer-sponsored (68.6%) with 44% requiring a copayment. The average copayment was $18 (range $2-$250) for those aged 25-64 compared with $5 in the 65+ group (range $0.62-$100). CONCLUSIONS: 17% of glaucoma patients aged 25-64 do not have coverage for their drops. One in four expressed concerns about the cost of their glaucoma medications, and 15.5% reported cost-related nonadherence.