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.

Five-year treatment outcomes in the Ahmed Baerveldt comparison study.

PURPOSE: To compare the 5-year outcomes of the Ahmed FP7 Glaucoma Valve (AGV) (New World Medical, Cucamonga, CA) and the Baerveldt 101-350 Glaucoma Implant (BGI) (Abbott Medical Optics, Abbott Park, IL) for the treatment of refractory glaucoma. DESIGN: Multicenter, randomized, controlled clinical trial. PARTICIPANTS: A total of 276 patients, including 143 in the AGV group and 133 in the BGI group. METHODS: Patients aged 18 to 85 years with previous intraocular surgery or refractory glaucoma and intraocular pressure (IOP) of ≥18 mmHg in whom glaucoma drainage implant (GDI) surgery was planned were randomized to implantation of an AGV or a BGI. MAIN OUTCOME MEASURES: Surgical failure, IOP, visual acuity (VA), use of glaucoma medications, and complications. RESULTS: At 5 years, IOP (mean ± standard deviation [SD]) was 14.7±4.4 mmHg in the AGV group and 12.7±4.5 mmHg in the BGI group (P = 0.015). The number of glaucoma medications in use at 5 years (mean ± SD) was 2.2±1.4 in the AGV group and 1.8±1.5 in the BGI group (P = 0.28). The cumulative probability of failure during 5 years of follow-up was 44.7% in the AGV group and 39.4% in the BGI group (P = 0.65). The number of subjects failing because of inadequately controlled IOP or reoperation for glaucoma was 46 in the AGV group (80% of AGV failures) and 25 in the BGI group (53% of BGI failures; P = 0.003). Eleven eyes in the AGV group (20% of AGV failures) experienced persistent hypotony, explantation of implant, or loss of light perception compared with 22 eyes (47% of failures) in the BGI group. Change in logarithm of the minimum angle of resolution VA (mean ± SD) at 5 years was 0.42±0.99 in the AGV group and 0.43±0.84 in the BGI group (P = 0.97). CONCLUSIONS: Similar rates of surgical success were observed with both implants at 5 years. The BGI produced greater IOP reduction and a lower rate of glaucoma reoperation than the AGV, but the BGI was associated with twice as many failures because of safety issues.

Assessment of the quality of glaucoma referral letters based on a survey of glaucoma specialists and a glaucoma guideline.

OBJECTIVE: To assess the quality of glaucoma referral letters and to report on the results of a survey of glaucoma specialists about referral letter content. DESIGN: Cross-sectional study. PARTICIPANTS: A survey of 135 glaucoma specialists and audit of 200 consecutive referral letters to a tertiary glaucoma unit. METHODS: An online questionnaire was sent to members of the Canadian and American Glaucoma Societies asking what they considered the most important data to be included in a glaucoma referral. Consecutive referral letters to a tertiary glaucoma unit were assessed for legibility and content on the basis of the survey results and information items in current guidelines. MAIN OUTCOME MEASURES: Survey outcome and proportion of included content items in referral letters. RESULTS: The survey revealed that the top 5 most important data that glaucoma specialists would like to be included in a referral letter for progressive glaucoma were serial visual fields (VFs), current glaucoma therapy, current intraocular pressure (IOP), maximum IOP, and serial disc imaging. These items often were omitted in the referral letters audited. A total of 200 referral letters were assessed, 46% from ophthalmologists, 42% from optometrists, 10% from family practitioners, and 2% from other sources. Reasons for referral were diagnosis of glaucoma (37%), unstable glaucoma (25%), angle assessment (17%), and others (21%). Some 26% of the referral letters were deemed illegible (18% from ophthalmologists vs. 6% from optometrists; P< 0.01). Degree of urgency was mentioned in 27% of referrals. Optometrists were more likely than ophthalmologists to provide visual acuity (VA), IOP, refraction, and VFs (P< 0.01 for each). Some 24% of referrals for progression included more than 10 of the 14 information points suggested by the Canadian glaucoma guidelines, and 34% included fewer than 8 of the 14 points. CONCLUSIONS: Referral letters frequently did not include important information, with 34% of referral letters deemed substandard. Optometrist referrals were better than ophthalmologist referrals in terms of content and legibility. A checklist of clinical details for referring physicians is suggested, which includes maximum and current IOP, disc evaluation, serial VFs, and serial disc imaging.

Three-year treatment outcomes in the Ahmed Baerveldt comparison study.

PURPOSE: To compare 3-year outcomes and complications of the Ahmed FP7 Glaucoma Valve (AGV) (New World Medical, Cucamonga, CA) and the Baerveldt Glaucoma Implant (BGI) 101-350 (Abbott Medical Optics, Abbott Park, IL) for the treatment of refractory glaucoma. DESIGN: Multicenter, randomized, controlled clinical trial. PARTICIPANTS: A total of 276 patients: 143 in the AGV group and 133 in the BGI group. METHODS: Patients aged 18 to 85 years with refractory glaucoma and intraocular pressures (IOPs) ≥ 18 mmHg in whom an aqueous shunt was planned were randomized to an AGV or a BGI. MAIN OUTCOME MEASURES: The IOP, visual acuity (VA), supplemental medical therapy, complications, and failure (IOP >21 mmHg or not reduced by 20% from baseline, IOP <5 mmHg, reoperation for glaucoma or removal of implant, or loss of light perception vision). RESULTS: At 3 years, IOP (mean ± standard deviation) was 14.3 ± ± 4.7 mmHg (AGV group) and 13.1 ± 4.5 mmHg (BGI group) (P = 0.086) on 2.0 ± 1.4 and 1.5 ± 1.4 glaucoma medications, respectively (P = 0.020). The cumulative probabilities of failure were 31.3% (standard error [SE], 4.0%) (AGV) and 32.3% (4.2%) (BGI) (P = 0.99). Postoperative complications associated with reoperation or vision loss of >2 Snellen lines occurred in 24 patients (22%) (AGV) and 38 patients (36%) (BGI) (P = 0.035). The mean change in the logarithm of the minimum angle of resolution VA at 3 years was similar (AGV: 0.21 ± 0.88, BGI: 0.26 ± 0.74) in the 2 treatment groups at 3 years (P = 0.66). The cumulative proportion of patients (SE) undergoing reoperation for glaucoma before the 3-year postoperative time point was 14.5% (3.0%) in the AGV group compared with 7.6% (2.4%) in the BGI group (P = 0.053, log rank). The relative risk of reoperation for glaucoma in the AGV group was 2.1 times that of the BGI group (95% confidence interval, 1.0-4.8; P = 0.045, Cox proportional hazards regression). CONCLUSIONS: Implantation of the AGV was associated with the need for significantly greater adjunctive medication to achieve equal success relative to implantation of the BGI and resulted in a greater relative risk of reoperation for glaucoma. More subjects experienced serious postoperative complications in the BGI group than in the AGV group.

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.

Trabeculectomy with ExPRESS: weighing the benefits and cost.

PURPOSE OF REVIEW: As glaucoma surgeons continue to search for an improvement over trabeculectomy, the ExPRESS miniature glaucoma shunt has gained interest as a possible contender. Peer-reviewed literature on ExPRESS is beginning to accumulate allowing an evidence-based review to assess the potential benefits and limitations compared to trabeculectomy. RECENT FINDINGS: The current surgical procedure for ExPRESS implantation will be described followed by results of studies comparing ExPRESS to trabeculectomy, focusing on the following outcomes: success, intraocular pressure, and complications. Case reports of late complications specific to the ExPRESS device will be summarized. Finally, an economic analysis comparing ExPRESS to trabeculectomy will be provided as additional evidence to contribute to the decision matrix on deciding which filtration procedure to recommend. SUMMARY: Despite a large number of ExPRESS implant procedures worldwide, there is a paucity of high-quality studies comparing ExPRESS to trabeculectomy. From the available literature to date the outcomes (success and early complications) of ExPRESS are similar to trabeculectomy. Reports of late complications related to device extrusion and malposition are beginning to be published; however, the significantly increased cost for ExPRESS surgery is likely to be the main limitation to widespread adoption of this procedure.

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.

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.

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.

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.

Subspecialization in glaucoma surgery.

PURPOSE: To evaluate trends in glaucoma surgery subspecialization. DESIGN: Population-based analysis of incisional glaucoma surgery and laser trabeculoplasty practice patterns among all ophthalmologists in Ontario, Canada, from 1995 through 2010. PARTICIPANTS: All ophthalmologists in Ontario, Canada, providing universal health care for the provincial population of approximately 12 million. METHODS: The province of Ontario provides government-funded universal health care insurance to all citizens through the Ontario Health Insurance Plan (OHIP). Anonymized physician services data were obtained from the OHIP database, which has excellent accuracy for procedure performance. MAIN OUTCOME MEASURES: Proportion of ophthalmologists providing incisional glaucoma surgery and laser trabeculoplasty and the distribution of these surgical and laser procedures among ophthalmologists. RESULTS: Between 1995 and 2010, the median number of ophthalmologists in Ontario was 427 (35.1 per 1 million population), ranging from 417 to 453 (32.9-40.3 per 1 million population). The percentage of ophthalmologists providing incisional glaucoma surgery dropped from 35% in 1995 to 19% in 2010, a 47% decline. Over the same period, the mean number of incisional glaucoma surgeries performed per surgeon doubled, and the percentage of incisional glaucoma operations provided by high-volume surgeons rose from 23% to 59%. The percentage of ophthalmologists performing laser trabeculoplasty was relatively stable (48% in 1995 to 50% in 2010). CONCLUSIONS: Over the past 16 years, the proportion of ophthalmologists providing incisional glaucoma surgery has declined significantly. At the same time, the proportion of incisional glaucoma surgery provided by high-volume glaucoma surgeons has more than doubled. These trends will have important implications for stakeholders from policy makers and hospitals to academic departments and residency education programs.

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.

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.