Surgical Outcomes among Focused versus Diversified Cataract Surgeons.

PURPOSE: Narrowly focused surgical practice has become increasingly common in ophthalmology and may have an effect on surgical outcomes. Previous research evaluating the influence of surgical focus on cataract surgical outcomes has been lacking. This study aimed to evaluate whether surgeons' exclusive surgical focus on cataract surgery influences the risk of cataract surgical adverse events. DESIGN: Population-based cohort study. PARTICIPANTS: All patients 66 years of age or older undergoing cataract surgery in Ontario, Canada, between January 1, 2002, and December 31, 2013. METHODS: Outcomes of isolated cataract surgery performed by exclusive cataract surgeons (no other types of surgery performed), moderately diversified cataract surgeons (1%-50% noncataract procedures), and highly diversified cataract surgeons (>50% noncataract procedures) were evaluated using linked healthcare databases and controlling for patient-, surgeon-, and institution-level covariates. Surgeon-level covariates included both surgeon experience and surgical volume. MAIN OUTCOME MEASURES: Composite outcome incorporating 4 adverse events: posterior capsule rupture, dropped lens fragments, retinal detachment, and suspected endophthalmitis. RESULTS: The study included 1 101 864 cataract operations. Patients had a median age of 76 years, and 60.2% were female. Patients treated by the 3 groups of surgeons were similar at baseline. Adverse events occurred in 0.73%, 0.78%, and 2.31% of cases performed by exclusive cataract surgeons, moderately diversified surgeons, and highly diversified surgeons, respectively. The risk of cataract surgical adverse events for patients operated on by moderately diversified surgeons was not different than for patients operated on by exclusive cataract surgeons (odds ratio [OR], 1.08; 95% confidence interval [CI], 1.00-1.18). Patients operated on by highly diversified surgeons had a higher risk of adverse events than patients operated on by exclusive cataract surgeons (OR, 1.52; 95% CI, 1.09-2.14). This resulted in an absolute risk difference of 0.016 (95% CI, 0.012-0.020) and a number needed to harm of 64 (95% CI, 50-87). CONCLUSIONS: Exclusive surgical focus did not affect the safety of cataract surgery when compared with moderate levels of surgical diversification. The risk of cataract surgical adverse events was higher among surgeons whose practice was dedicated mainly to noncataract surgery.

Preoperative measurements for cataract surgery: a comparison of ultrasound and optical biometric devices.

PURPOSE: To evaluate differences in preoperative measurements and refractive outcomes between ultrasound and optical biometry when using the Barrett Universal II intraocular lens (IOL) power formula. METHODS: In this consecutive case series, cataract extraction and IOL implantation cases from two surgical centers in Toronto, Canada, were recruited between January 2015 and July 2017. Differences between ultrasound (applanation or immersion A-scan) and optical biometry (IOLMaster 500) were compared for axial length (AL), anterior chamber depth and refractive outcomes. The primary outcome was the percentage of cases in each cohort within ± 0.50D of refractive error. RESULTS: In total, 527 cataract cases underwent IOLMaster testing. Of these, 329 eyes (62.4%) were also measured by applanation A-scan, and the other 198 eyes (37.6%) received immersion A-scan testing. Applanation ultrasound led to 5.8%, 16.0% and 46.4% of eyes within ± 0.25D, ± 0.50D and ± 1.00D of refractive error, respectively, whereas the IOLMaster 500 led to 48.5%, 77.1% and 94.9%, respectively (n = 293, ± 0.50D: p < 0.001). Immersion ultrasound led to 31.2%, 57.6% and 91.2% of eyes within ± 0.25D, ± 0.50D and ± 1.00D of refractive error, respectively, whereas the IOLMaster 500 led to 42.4%, 72.0% and 92.0%, respectively (n = 125, ± 0.50D: p = 0.001). Applanation (n = 329, A-scan AL: 23.64 ± 1.67 mm, IOLMaster AL: 24.20 ± 1.70 mm, p < 0.001) and immersion ultrasound (n = 198, A-scan AL: 25.01 ± 2.06 mm, IOLMaster AL: 25.08 ± 2.13 mm, p = 0.002) yielded significantly lower AL values compared to optical biometry measurements. CONCLUSIONS: Optical biometry yielded a significantly larger percentage of cases within ± 0.50D of refractive error compared to ultrasound biometry when using the Barrett Universal II IOL power formula.

A comparative analysis of 12 intraocular lens power formulas.

PURPOSE: To evaluate the accuracy of 12 intraocular lens (IOL) power calculations: Barrett Universal II, EVO, Haigis, Hill-RBF version 2.0, Hoffer Q, Holladay 1, Holladay 2, Kane, Olsen, SRK/T, Super Formula and T2. METHODS: In this retrospective consecutive case series, cataract extraction and IOL implantation cases in Toronto, Canada, were recruited between 2017 and 2019. Refractive predictions were compared to the observed 1-month postoperative spherical equivalent to determine the refractive error for each formula cohort. Subgroup analysis stratified eyes into short (≤ 22.5 mm)-, intermediate (22.5 mm-25.5 mm)- and long (≥ 25.5 mm)-axial length (AL) cohorts. The primary outcome was the percentage of cases within ± 0.50D of refractive error. RESULTS: Overall, 764 cataract cases were analyzed. Formulas with the highest percentage of eyes within ± 0.50D of refractive error, in decreasing order, were: Kane (77.7%), Barrett Universal II (77.4%), EVO (76.6%), T2 (76.4%), Super (75.9%), Holladay 1 (75.4%), Hill-RBF 2.0 (74.7%), SRK/T (72.6%), Hoffer Q (72.5%), Haigis (71.7%), Olsen (67.4%) and Holladay 2 (67.3%). For short-AL eyes, the Holladay 1 formula was most accurate (n = 69, 78.3% within ± 0.50D), and for long-AL eyes, the Barrett Universal II formula was most accurate (n = 116, 76.7% within ± 0.50D). Kane, Barrett, EVO, T2 and Super formulas led to a significantly lower mean absolute error compared to the open-source calculations with optimized lens constants (p-value: < 0.001-0.042). CONCLUSIONS: The Kane formula was the most accurate formula for the overall analysis. The Holladay 1 calculation was most accurate for short-AL cases, whereas the Barrett Universal II was superior for long-AL eyes.

Evolution in the Risk of Cataract Surgical Complications among Patients Exposed to Tamsulosin: A Population-Based Study.

PURPOSE: Tamsulosin is associated with intraoperative floppy iris syndrome (IFIS), an important risk factor for complications during cataract surgery. Significant efforts have been made to increase awareness of the risks associated with tamsulosin, and educational initiatives have fostered the uptake of technical adjustments to decrease adverse event rates among tamsulosin-exposed patients. However, the effectiveness of these efforts at the population level has not been studied. DESIGN: Population-based study to evaluate cataract surgical adverse event rates over time among patients exposed to tamsulosin and those not exposed to this drug. PARTICIPANTS: All male patients 66 years of age and older undergoing cataract surgery in Ontario, Canada, between January 1, 2003, and December 31, 2013, were included in the study. METHODS: Linked healthcare databases were used to study the evolution in the risk of cataract surgical adverse events over time among tamsulosin-exposed and non-tamsulosin-exposed patients adjusting for patient-, surgeon-, and institution-level covariates. The study timeframe incorporated periods before and after the first reports of tamsulosin-associated IFIS. MAIN OUTCOME MEASURES: Four important cataract surgical adverse events were evaluated: posterior capsule rupture, dropped lens fragments, retinal detachment, and suspected endophthalmitis. RESULTS: Among patients exposed to tamsulosin, the risk of surgical adverse events decreased over time (odds ratio, 0.95 per year; 95% confidence interval, 0.91-0.99 per year). This trend was observed across patient age strata. Among patients not recently exposed to tamsulosin, the risk of surgical adverse events also decreased over time (odds ratio, 0.96 per year; 95% confidence interval, 0.95-0.98 per year). CONCLUSIONS: The risk of cataract surgical complications among both tamsulosin-exposed and non-tamsulosin-exposed patients declined between 2003 and 2013. Tamsulosin remains an important risk factor for cataract surgical adverse events, and ongoing efforts will be needed to develop and disseminate surgical approaches that mitigate the risks posed by tamsulosin.

Cataract Surgery Quality and Capacity.

Cataract surgery is the most common operation performed in most developed countries, including Canada. Nuanced, evidence-driven policies are needed to ensure appropriate access to this sight-saving operation while maintaining the highest standards in quality of care. The Vision Health Services Research Program at Queen's University, in partnership with members of the Ontario Provincial Vision Task Force, has developed evidence to inform policies aimed at optimizing both access and quality across the eye care spectrum.

New Surgeon Outcomes and the Effectiveness of Surgical Training: A Population-Based Cohort Study.

PURPOSE: Reports have questioned the technical proficiency of newly graduating surgeons. However, objective data supporting these concerns are limited. Surgical outcomes among recent graduates are an important indicator of residency programs' ability to graduate surgeons who are ready to meet the needs of their patients. This study aimed to investigate the association between a surgeon's number of years of independent practice and the risk of surgical adverse events. DESIGN: Population-based cohort study. PARTICIPANTS: All patients 66 years of age or older undergoing isolated cataract operations in Ontario, Canada, between January 1, 1997, and December 31, 2013. METHODS: Cataract surgical outcomes for all operations performed by surgeons commencing practice in the study period were evaluated using linked health care databases. MAIN OUTCOME MEASURES: Four serious complications were evaluated: posterior capsule rupture, dropped lens fragments, retinal detachment, and suspected endophthalmitis. Analyses controlled for patient-, surgeon-, and institution-level covariates. RESULTS: The study evaluated 1 431 320 cataract operations. Surgeons in their first year of independent practice were more than 9 times more likely to have high complication rates (≥2%) than surgeons in their tenth year (odds ratio [OR], 9.3; 95% confidence interval [CI], 2.7-31.9). Each additional year of independent practice was associated with a 10% decrease in the risk of patients experiencing an adverse surgical event (OR, 0.90 per year of surgeon independent practice; 95% CI, 0.87-0.94). CONCLUSIONS: In this population-based study, surgical complications were significantly more likely early in surgeons' careers. Interventions may be needed in postgraduate surgical training and early independent career monitoring and mentoring processes to ensure patient safety while continually renewing the surgical workforce.

Cost-Utility Analysis of Extending Public Health Insurance Coverage to Include Diabetic Retinopathy Screening by Optometrists.

BACKGROUND: Diabetic retinopathy (DR) is one of the leading causes of vision loss and blindness in Canada. Eye examinations play an important role in early detection. However, DR screening by optometrists is not always universally covered by public or private health insurance plans. This study assessed whether expanding public health coverage to include diabetic eye examinations for retinopathy by optometrists is cost-effective from the perspective of the health care system. METHODS: We conducted a cost-utility analysis of extended coverage for diabetic eye examinations in Prince Edward Island to include examinations by optometrists, not currently publicly covered. We used a Markov chain to simulate disease burden based on eye examination rates and DR progression over a 30-year time horizon. Results were presented as an incremental cost per quality-adjusted life year (QALY) gained. A series of one-way and probabilistic sensitivity analyses were performed. RESULTS: Extending public health coverage to eye examinations by optometrists was associated with higher costs ($9,908,543.32) and improved QALYs (156,862.44), over 30 years, resulting in an incremental cost-effectiveness ratio of $1668.43/QALY gained. Sensitivity analysis showed that the most influential determinants of the results were the cost of optometric screening and selected utility scores. At the commonly used threshold of $50,000/QALY, the probability that the new policy was cost-effective was 99.99%. CONCLUSIONS: Extending public health coverage to eye examinations by optometrists is cost-effective based on a commonly used threshold of $50,000/QALY. Findings from this study can inform the decision to expand public-insured optometric services for patients with diabetes.

Effect of cataract surgery volume constraints on recently graduated ophthalmologists: a population-based cohort study.

BACKGROUND: Across Canada, graduates from several medical and surgical specialties have recently had difficulty securing practice opportunities, especially in specialties dependent on limited resources such as ophthalmology. We aimed to investigate whether resource constraints in the health care system have a greater impact on the volume of cataract surgery performed by recent graduates than on established physicians. METHODS: We used population-based administrative data from Ontario for the period Jan. 1, 1994, to June 30, 2013, to compare health services provided by recent graduates and established ophthalmologists. The primary outcome was volume of cataract surgery, a resource-intensive service for which volume is controlled by the province. RESULTS: When cataract surgery volume in Ontario entered a period of government-mandated zero growth in 2007, the mean number of cataract operations performed by recent graduates dropped significantly (-46.37 operations/quarter, 95% confidence interval [CI] -62.73 to -30.00 operations/quarter), whereas the mean rate for established ophthalmologists remained stable (+5.89 operations/quarter, 95% CI 95% CI -1.47 to +13.24 operations/quarter). Decreases in service provision among recent graduates did not occur for services without volume control. The proportion of recent graduates providing exclusively cataract surgery increased over the study period, and recent graduates in this group were 5.24 times (95% CI 2.15 to 12.76 times) more likely to fall within the lowest quartile for cataract surgical volume during the period of zero growth in provincial cataract volume (2007-2013) than in the preceding period (1996-2006). INTERPRETATION: Recent ophthalmology graduates performed many fewer cataract surgery procedures after volume controls were implemented in Ontario. Integrated initiatives involving multiple stakeholders are needed to address the issues facing recently graduated physicians in Canada.

Anti-inflammatory therapy after selective laser trabeculoplasty: a randomized, double-masked, placebo-controlled clinical trial.

PURPOSE: To investigate the effect of anti-inflammatory therapy on selective laser trabeculoplasty (SLT) outcomes. DESIGN: Randomized, double-masked, placebo-controlled trial. PARTICIPANTS: Patients with primary open-angle or pseudo-exfoliation glaucoma. METHODS: Patients undergoing SLT were randomized to receive placebo (artificial tears), prednisolone acetate 1%, or ketorolac tromethamine 0.5% eye drops 4 times per day for 5 days commencing immediately after SLT. MAIN OUTCOME MEASURES: Change in intraocular pressure (IOP) from baseline to the 1-month post-SLT visit. RESULTS: Mean change in IOP at the 1-month primary outcome time point, as well as all other time points, was not significantly different among groups (P = 0.99). Likewise, a repeated-measures, mixed-effects model did not find significant differences in IOP outcome at the 1-month time point (P = 0.95). The IOP was reduced in all groups at the 1-month post-SLT time point and all other time points, and no significant differences were found between groups using separate unadjusted cross-sectional analyses of variance (P > 0.15 for analyses at all time points). Treatment failure rates were not different among groups (P = 0.75), and at 1 year after SLT, the percentage of patients maintaining a 20% IOP reduction ranged from 18% to 22% in the 3 study groups. CONCLUSIONS: Anti-inflammatory therapy after SLT does not seem to substantially influence the IOP-lowering effect of SLT. In this study of patients with low baseline IOP, SLT showed limited efficacy in achieving a sustained reduction in IOP.

Prediction accuracy of intraoperative aberrometry compared with preoperative biometry formulae for intraocular lens power selection.

OBJECTIVE: To compare the accuracy of intraoperative wavefront aberrometry to preoperative biometry formulae for predicting intraocular lens power. DESIGN: Retrospective, consecutive case series. PARTICIPANTS: Eyes undergoing cataract extraction with at least 1 month of follow-up after surgery at an ambulatory surgical centre in Toronto. METHODS: Consecutive sample of 228 cataract extractions with monofocal, trifocal, or toric intraocular lens implantation from November 1, 2017, to December 31, 2019. The spherical equivalent was predicted preoperatively with Barrett Universal II, Hill-Radial Basis Function (RBF), SRK/T, Holladay I, Holladay II, Haigis, and HofferQ using biometry measurements and intraoperatively with wavefront aberrometry. The primary outcomes were mean prediction error and proportion of eyes with a spherical equivalent within 0.5 D of the refractive target at postoperative month 1. RESULTS: The analysis included 159 eyes with 52% females and a mean age of 69.4 years. Formulae with the lowest mean prediction error were Hill-RBF (0.32 D ± 0.02 D), Barrett Universal II (0.32 D ± 0.02 D), intraoperative aberrometry (0.32 D ± 0.02 D), SRK/T (0.33 D ± 0.02 D), Holladay II (0.34 D ± 0.03 D), Holladay I (0.35 D ± 0.02 D), Haigis (0.37 D ± 0.02 D), and HofferQ (0.42 D ± 0.02 D). There were no statistically significant differences between intraoperative aberrometry and the preoperative formulae. Formulae with the highest proportion of eyes within 0.5 D of the refractive target were intraoperative aberrometry (82%), Barrett Universal II (81%), Hill-RBF (80%), SRK/T (77%), Holladay II (76%), Holladay I (75%), Haigis (71%), and HofferQ (70%). CONCLUSIONS: Intraoperative aberrometry and modern preoperative biometry formulae are equally effective at reaching the refractive target. In normal eyes, intraoperative aberrometry does not appear to provide any additional benefit to modern prediction formulae.

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.

Eye protection following cataract surgery: a systematic review.

BACKGROUND: There is a high variability in the use of postoperative eye protection among ophthalmologists. Postoperative eye protection treatment modalities include an eye shield, an eye patch, an ocular bandage, and instant vision. The aim of this study was to review and compare the evidence on the various options for eye protection. METHODS: A systematic literature search was conducted, and original comparative articles that reported on subjective symptoms (e.g., foreign-body sensation, photophobia, tearing, and pain) and postoperative outcomes (e.g., tear film breakup time, best-corrected visual acuity, etc.) after usage of an eye protection method were included. RESULTS: Overall, 598 eyes across 8 articles were included. Included studies investigated ocular bandages (n = 6), eye patches (n = 4), instant vision (n = 2), and eye shields (n = 1) postoperatively. In 5 studies, patients receiving ocular bandages self-reported symptoms, including pain (n = 3), foreign-body sensation (n = 4), photophobia (n = 3), and tearing (n = 3), at a reduced or equivalent rate compared with other treatment modalities. With the ocular bandage, 3 studies reported increased tear film breakup time, and 1 study reported improvements in corneal wound healing compared with a control group. Two studies reported reduced tear film breakup time for the eye patch relative to the ocular bandage, and another study reported reduced tear film breakup time for instant vision compared with the eye patch. CONCLUSIONS: Patient-reported symptoms are acutely reduced for patients receiving an ocular bandage relative to instant vision following cataract surgery. Patients prefer receiving some form of postoperative protection as opposed to instant vision.

Preoperative evaluations for ophthalmic surgery: A systematic review of 48,869 eyes.

Eliminating low-yield testing can reduce the burden on modern health care systems. Our purpose is to determine whether routine preoperative assessment impacts the incidence of perioperative complications in ophthalmic surgery. We conducted a comprehensive search of Ovid MEDLINE, EMBASE, and Cochrane Library databases to identify studies investigating the incidence of perioperative complications following any preoperative assessment for patients undergoing ophthalmic surgery (PROSPERO ID#164008). Four randomized controlled trials (RCTs) and 5 observational studies were selected for inclusion. Risk of bias assessment revealed a lack of masking and insufficient statistical power in RCTs, and confounding in observational studies. Routine preoperative testing-including laboratory tests, electrocardiogram, and imaging studiesdid not decrease the incidence of adverse events or risk of perioperative ocular and systemic complications in most studies. Two cohort studies (1 retrospective, 1 prospective) suggestd that patients with certain preexisting health conditions were at increased risk for adverse events perioperatively. Another retrospective study found a lower risk of complications in high-risk patients who underwent evaluation. While patients with comorbidities may be at increased risk of adverse events, the role of preoperative assessment is not well delineated in this population. Further study is required to determine the comparative safety, effectiveness, and implementation of alternative assessment tools.

A retrospective population-based analysis of wait times for cataract surgery in Ontario, Canada.

BACKGROUND: Current methods used to estimate surgical wait times in Ontario may be subject to inconsistencies and inaccuracies. In this population-level study, we aimed to estimate cataract surgery wait times in Ontario using a novel, objective and data-driven method. METHODS: We identified adults who underwent cataract surgery between 2005 and 2019 in Ontario, using administrative records. Wait time 1 represented the number of days from referral to initial visit with the surgeon, and wait time 2 represented the number of days from the decision for surgery until the first eye surgery date. In the primary analysis, a ranking method prioritized referrals from optometrists, followed by ophthalmologists and family physicians. RESULTS: The cohort consisted of 1 138 532 people with mostly female patients (57.4%) and those aged 65 years and older (79.0%). In the primary analysis, the median was 67 days for wait time 1 (interquartile range [IQR] 29-147). There was a median of 77 days for wait time 2 (IQR 37-155). Overall, the following proportions of patients waited less than 3, 6 and 12 months: 54.1%, 78.5% and 91.7%, respectively. For wait time 2, the proportions of patients who waited less than 3, 6 and 12 months were 49.5%, 77.1% and 93.3%, respectively. In total, 19.3% of patients did not meet the provincial target for wait time 1, 20.5% did not meet the target for wait time 2 and 35.0% did not meet the target for wait times 1 or 2. INTERPRETATION: Administrative health services data can be used to estimate cataract surgery wait times. With this method, 35.0% of patients in 2005-2019 did not receive initial consultation or surgery within the provincial wait time target.

Validation of a novel patient satisfaction questionnaire for preoperative fasting in cataract surgery: a discrimination analysis.

OBJECTIVE: Preoperative fasting is routinely performed to prevent anaesthesia-related pulmonary aspiration. To capture patients' experiences with preoperative fasting, a 13-item questionnaire was developed and validated using Rasch analysis and shortened to 6 items. This extension study aims to assess this questionnaire's ability to discriminate between participants with a short versus long duration of fasting and early versus late day surgery. DESIGN: Single-centred cross-sectional study. PARTICIPANTS: Subjects were recruited via consecutive sampling of cataract patients on surgery day at Kensington Eye Institute in Toronto from February to December 2019. METHODS: A validated preoperative fasting questionnaire was administered. Discriminative ability was assessed by comparing responses in patients scheduled for surgery in the morning (8:00 am-12:00 pm) versus afternoon (12:00 pm-3:30 pm) and fasting for short (≤8 hours) versus long (>8 hours) duration. Diagnostic ability of the 6-item questionnaire relative to the 13-item questionnaire was assessed with receiver operating characteristics curve analysis. RESULTS: A total of 164 patients (mean age 70.8 ± 10.0 years; 57% female) were included. Total scores of patients having surgery in the morning were greater (i.e., less fasting-related burden) than in the afternoon (p = 0.04). There was no significant difference in scores between patients fasting for a short versus long duration (p > 0.05). Receiver operating characteristics curve analysis showed excellent diagnostic ability of the 6-item questionnaire relative to the 13-item version (area under the curve = 0.964). CONCLUSION: The 6-item questionnaire for fasting-related burden has excellent discriminative ability between early versus late surgery patients. The time fasting while awake may be a more relevant predictor of fasting-related burden relative to the total duration of fasting.

Multi-center validation of Catquest-9SF visual function questionnaire in Ontario, Canada.

PURPOSE: To investigate the psychometric performance and responsiveness of Catquest-9SF, a patient-reported questionnaire developed to evaluate visual function as related to daily tasks, in patients referred for cataract surgery in Ontario, Canada. METHODS: This is a pooled analysis on prospective data collected for previous projects. Subjects were recruited from three tertiary care centers in Peel region, Hamilton, and Toronto, Ontario, Canada. Catquest-9SF was administered pre-operative and post-operatively to patients with cataract. Psychometric properties, including category threshold order, infit/outfit, precision, unidimensionality, targeting, and differential item functioning were tested using Rasch analysis with Winsteps software (v.4.4.4) for Catquest-9SF. Responsiveness of questionnaire scores to cataract surgery was assessed. RESULTS: 934 patients (mean age = 71.6, 492[52.7%] female) completed the pre- and post-operative Catquest-9SF questionnaire. Catquest-9SF had ordered response thresholds, adequate precision (person separation index = 2.01, person reliability = 0.80), and confirmed unidimensionality. The infit range was 0.75-1.29 and the outfit range was 0.74-1.51, with one item ('satisfaction with vision') misfitting (outfit value = 1.51). There was mistargeting of -1.07 in pre-operative scores and mistargeting of -2.43 in both pre- and post-operative scores, meaning that tasks were relatively easy for respondent ability. There was no adverse differential item functioning. There was a mean 1.47 logit improvement in Catquest-9SF scores after cataract surgery (p<0.001). CONCLUSION: Catquest-9SF is a psychometrically robust questionnaire for assessment of visual function in patients with cataract in Ontario, Canada. It is also responsive to clinical improvement after cataract surgery.

Ontario Cataract Quality Outcome Initiative: appropriateness and prioritization of cataract surgery.

OBJECTIVE: To explore the utility of the Catquest 9SF visual function (VF) questionnaire along with visual acuity (VA) for determining appropriateness and priority for cataract surgery. To evaluate the feasibility of administering the Catquest-9SF in a clinical setting using web-based electronic data capture and interpretation. DESIGN: Prospective multicentred interventional observational study. PARTICIPANTS: Subjects undergoing sequential cataract surgery in both eyes at 4 sites in Ontario. METHODS: We recorded best-corrected VA (BCVA) and VA with current correction (CCVA) in each eye and both eyes (OU) and Catquest-9SF responses on a tablet before and after cataract surgery. Linear regression models were employed to test for associations between VA and visual function (VF). RESULTS: Preoperative BCVA and CCVA in the worse eye were significant predictors of change in VF (p = 0.006 and p = 0.008, respectively); subjects with worse VA had a greater improvement in VF after surgery. There was a significant association between improvement in VF and improvement in CCVA OU (p = 0.001). Fourteen of 151 subjects (9%) had no improvement or worse VF scores after surgery. Within this group, 10 of 14 subjects had a preoperative score ≤-3, which is suggestive of minimal visual disability. Within this subset, 4 of 14 subjects (2.6%) had a preoperative BCVA of 20/30 or better in their worse eye. CONCLUSIONS: For patient groups with equal VA, the Catquest-9SF score can help determine priority for surgery. Web-based data capture and interpretation allow for efficient virtual assessments of VF. A BCVA in the worse eye of 20/30 or better combined with a Catquest-9SF score <-3 can be used as a guideline for lowest priority.

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.

Clinical features of endophthalmitis clusters after cataract surgery and practical recommendations to mitigate risk: systematic review.

Intraocular transmission of exogenous pathogens in cataract surgery can lead to endophthalmitis. This review evaluates the features of endophthalmitis clusters secondary to pathogen transmission in cataract surgery. Articles reporting on pathogen transmission in cataract surgery were identified via searches of Ovid MEDLINE, EMBASE, and Cochrane CENTRAL, and a total of 268 eyes from 24 studies were included. The most common source of infectious transmission was attributed to a contaminated intraocular solution (ie, irrigation solution, viscoelastic, or diluted antibiotic; n = 10). Visual acuity at presentation with infectious features was 1.89 logMAR (range: 1.35 to 2.58; ∼counting fingers) and 1.33 logMAR (range: 0.04 to 3.00; Snellen: ∼20/430) at last follow-up. Patients with diabetes had worse outcomes compared with patients without diabetes. The most frequently isolated pathogen from the infectious sources was Pseudomonas sp. (50.0%). This review highlights the various routes of pathogen transmission during cataract surgery and summarizes recommendations for the detection, prevention, and management of endophthalmitis clusters.