Search

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., Competing Interests: Competing interests: Marko Popovic has received research grant support from PSI Foundation and Fighting Blindness Canada. Matthew Schlenker has received consulting fees and speaker honoraria from Alcon and Allergan. He has also received speaker honoraria from Bausch Health, Johnson & Johnson Vision and Théa-Labtician. He has received consulting fees from Light Matter Interaction and Santen. Iqbal Ahmed has received consulting fees from Aequus, Aerie Pharmaceuticals, Akorn, Alcon, Allergan, Aquea Health, Inc, ArcScan, Bausch Health, Beaver Visitec, Beyeonics, Carl Zeiss Meditec, Centricity Vision, Inc., CorNeat Vision, Costum Surgical, ELT Sight, ElutiMed, Equinox, Genentech, Glaukos, Gore, Iantrek, InjectSense, Iridex, iStar, Ivantis, Johnson & Johnson Vision, LayerBio, Leica Microsystems, Long Bridge Medical, Inc., MicroOptx, MST Surgical, New World Medical, Ocular Instruments, Ocular Therapeutix, Oculo, Omega Ophthalmics, PolyActiva, Radiance Therapeutics, Inc., Ripple Therapeutics, Sanoculis, Santen, Shifamed, LLC, Sight Sciences, Smartlens, Inc., Stroma, Thea Pharma, ViaLase and Vizzario. He has also received speaker honoraria from Alcon, Allergan, Carl Zeiss Meditec, Johnson & Johnson Vision and MST Surgical. No other competing interests were declared., (© 2023 CMA Impact Inc. or its licensors.)

Context: Funding surgery worldwide for age-related cataract (ARC), a leading cause of blindness, is a huge economic burden. Non-surgical means of slowing ARC progression could benefit patients and reduce this burden., Objective: To determine if a mixture of oral antioxidant micronutrients [mg/day] (beta-carotene [18], vitamin C [750], and vitamin E [600]) would modify progression of ARC., Design: REACT was a multi-centered, prospective, double-masked, randomized, placebo-controlled, 3-year trial., Setting: Consecutive adult American and English outpatients with early ARC were recruited., Patients: Four-hundred-and-forty-five patients were eligible; 297 were randomized; 231 (78%) were followed for two years; 158 (53%) were followed for three years; 36 (12%) were followed for four years. Twelve patients died during the trial (9 on vitamins; 3 on placebo (p = 0.07)). There were no serious safety issues., Intervention: After a three-month placebo run-in, patients were randomized by clinical center to the vitamin or placebo groups and followed every four months., Main Outcome Measure: Cataract severity was documented with serial digital retroillumination imagery of the lens; progression was quantified by image analysis assessing increased area of opacity. This measure of area, 'increase % pixels opaque' (IPO), was the main outcome measure., Results: There were no statistically significant differences between the treatment groups at baseline. The characteristics of dropouts and the mean follow-up times by treatment group were the same. After two years of treatment, there was a small positive treatment effect in U.S. patients (p = 0.0001); after three years a positive effect was apparent (p = 0.048) in both the U.S. and the U.K. groups. The positive effect in the U.S. group was even greater after three years: (IPO = 0.389 (vitamin) vs. IPO = 2.517 (placebo); p = 0.0001). There was no statistically significant benefit of treatment in the U.K. group. In spite of nearly perfect randomization into treatment groups, the U.S. and U.K. cohorts differed significantly., Conclusion: Daily use of the afore-mentioned micronutrients for three years produced a small deceleration in progression of ARC.

The Roche European-American Anticataract Trial (REACT) will assess the effect of antioxidants on progression of cataract in humans. This report evaluates the methods used in REACT. Seventy three subjects (139 eyes) with cortical (C), posterior subcapsular (P), nuclear (N) or mixed cataract were seen twice within two weeks for eye examinations, assessments of visual function, lens photographs and CCD images. The degree of cataract and nuclear color (NC) were assessed with subjective (LOCS III) and objective (computerized, CASE 2000 CCD) methods. Repeat visit values were used to calculate intraclass correlation coefficients (r1) and 95% tolerance limits (TL). A clinically significant change (CSC) was defined as one step in LOCS III. The relative power of each method to detect cataract change and sample sizes needed to achieve statistically significant results were calculated. The r1 values for visual function tests ranged from 0.76 to 0.88; if these tests of visual function were used to detect a clinically significant change in cataract severity, sample sizes of 840 to 2707 per group would be needed. The r1 values for LOCS III were 0.88 to 0.97, and sample sizes ranged from 50 to 135 per group. The r1 values for the CCD were 0.93 to 0.98, and sample sizes ranged from 1 to 42 with poorer values relating to measurement of P. We conclude that the methods used in REACT are reproducible. The analytical algorithms in the image analysis programs did not permit differentiation between C and P opacification; therefore, P cataract is best measured with LOCS III. REACT sample sizes are adequate to detect a difference of 0.2 LOCS III units/year between the mean rates of cataract progression in two groups.

Hyperacuity tasks have been suggested for the assessment of potential visual function in the presence of cataracts. To test this suggestion, hyperacuity thresholds for an oscillating bar were measured in 30 subjects with idiopathic cataract and in 24 age-matched normals over a range of oscillation frequencies. Each subject's cataract was categorized using the Oxford Clinical Cataract Classification and Grading System. Cataract was found to have a significant effect on thresholds, although a differential morphological effect on thresholds was equivocal. Thresholds at higher temporal frequencies were significantly raised when compared to the normal group. The main conclusion to be drawn from this study is that motion hyperacuity thresholds appear unaffected by cataract at low oscillation frequencies and should be used in preference to higher frequencies in the assessment of such patients.

The clinician involved in cataract assessment is often faced with a deterioration in visual performance which may or may not be totally attributable to the cataract. Neural changes may occur concurrently and contribute toward the reduced performance. This paper reviews the methods which attempt to discriminate between changes due to cataract development and changes produced by neural degeneration. New techniques have been developed with more emphasis on quantitative rather than qualitative assessment. These techniques are discussed critically with particular reference to their ability to distinguish between the contributions of optical and neural change. This has particular application in predicting the visual outcome after cataract surgery.

Among the 80 subjects who were recruited with normal retinal and neural function, 54 had cataract and a visual acuity (VA) better than 6/24. The 26 age-matched subjects had clear media. Contrast sensitivity (CS) at low and intermediate spatial frequencies was measured using the Pelli-Robson letter chart. Two measures of glare disability (GD) were obtained using the Mentor Brightness Acuity Tester (BAT) in conjunction with a logMAR VA chart and the Pelli-Robson chart. Although CS is predominantly affected at high spatial frequencies in early cataract, we found that some subjects had reduced scores on the Pelli-Robson chart. This CS loss could not be predicted from VA measurements and was particularly found in subjects with posterior subcapsular cataract. High GD scores were found in a number of subjects with relatively good VA and could not be predicted from results of VA or CS. We suggest that CS and GD measurements using the Pelli-Robson chart and the BAT provide valuable information regarding the management of patients with early cataract.

Conventional techniques for assessing the visual function of cataract patients include visual acuity (VA), contrast sensitivity (CS) and glare disability (GD). The extent to which these measurements provide accurate information about a patient's perceived visual disability is not known. In this study, binocular and monocular VA and CS and monocular GD measurements were made using commercially available techniques on 33 cataract patients. VA was measured using a Ferris-Bailey LogMAR chart and CS by the Pelli-Robson letter CS chart. Glare disability was measured using the Mentor Brightness Acuity Tester in conjunction with both the LogMAR and Pelli Robson charts. Each patient's perceived visual disability was quantified using a 20-point questionnaire about the effect of vision on everyday activities. There was little correlation between subjective visual disability and monocular or binocular VA measurements. Measurements of binocular CS, however, were highly correlated with the patient's perceived visual disability, particularly their subjective assessment of the effect of vision on their mobility-orientation. We suggest that binocular CS measurements using the Pelli-Robson chart provide useful additional information regarding the need for surgery in cataract patients.

The medical treatment of cataract now appears to be a distinct possibility. A number of anti-cataract formulations are being clinically tested, and more clinical trials are being planned. To obtain a true assessment of a drug's efficacy, a battery of tests are needed which can accurately assess cataract progress. A clinical trial of the proposed anti-cataract drug Bendalina is being conducted. The six subjective methods used to assess cataract progression in the trial are presented. These are refractive error, LogMAR visual acuity, contrast sensitivity, glare sensitivity, retinal visual acuity and displacement threshold hyperacuity. The reasons for using each technique and their method of measurement is explained.

The efficacy of a new clinical instrument which measures light backscatter from the crystalline lens--the Opacity Lensmeter 701--was assessed. Repeated measurements were made on 83 normal subjects in the age range 15 to 82 years, and on 38 eyes of subjects with cataract but normal retinal and neural function. The cataract scores were compared against results of Logmar visual acuity (VA) and glare disability measurements from the same subjects. The Lensmeter was found to be simple to use and gave quick, repeatable, objective measurements of light backscatter. Scores correlated well with normal age changes in noncataractous lenses and in cataracts of pure nuclear morphology, but not in cortical or posterior subcapsular cataracts.