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Purpose To describe the clinical spectrum and a new theory of pathogenesis of true exfoliation syndrome. Design Cross-sectional and prospective, observational case series. Participants Consecutive patients with characteristic peeling of the anterior lens capsule. Methods After maximal mydriasis, slit-lamp biomicroscopy, and photography, imaging of the anterior capsule and zonules was performed. The condition was classified into 4 clinical stages: annular anterior capsule thickening with a distinct splitting margin (stage 1), an inward detached crescentic flap lying on the anterior lens (stage 2), a floating and folding translucent membrane behind the iris (stage 3), and a broad membrane within the pupil (stage 4). Serial photography was performed at each 3-month follow-up visit. Ultrastructural examination of dislocated lenses and excised anterior capsules was performed. Main Outcome Measures Detached membrane morphologic features, zonular defects, pigment deposition, glaucoma, phacodonesis, and cataract. Results We enrolled 259 patients (424 eyes). Ages ranged from 52 to 97 years (mean age, 75.2±7.1 years). Eleven patients were associated with trauma (n = 1) or intense heat (n = 10), whereas 248 were idiopathic. Two hundred ten patients were followed up every 3 months, with a mean follow-up of 9.6±6.1 months (range, 3–50 months). The detachment started along the anterior zonular insertions in association with zonular disruption. It progressed centrally to higher stages, manifesting a spectrum of disease. Several stages coexisted in a single eye. At the final visit, including 49 patients who were examined once, there were 70, 87, 85, and 17 patients in stages 1, 2, 3, and 4, respectively. All stages shared common histologic findings consisting of diffuse capsular lamellar separation and anterior zonular disruption. All developed cataract. Pigment deposition on the membrane was present in 178 patients (68.7%). Twenty-six patients (10%) had spontaneous phacodonesis. Eighteen eyes (4.2%) demonstrated secondary delamination. Conclusions Capsular lamellar separation and anterior zonular disruption are characteristic findings. Aging, heat exposure, and trauma are risk factors. Initial capsular splits occur along the insertions of disrupted anterior zonules. The peeling progresses centrally in association with iris movement and aqueous flow. A second detachment can occur. [ABSTRACT FROM AUTHOR]

PURPOSE: To evaluate the efficacy of an iPod application developed to rapidly measure approximate visual acuity (VA). DESIGN: Prospective, cross-sectional study. METHODS: One hundred four subjects (104 eyes) with a wide range ofVAunderwent both Early Treatment Diabetic Retinopathy Study (ETDRS) VA testing and iPod application testing. The application presented 4 randomized ETDRS letters at the Snellen equivalent of 20/40 and 20/200 each. In separate analyses, sensitivity and specificity of the iPod test were determined using the ETDRS VA testing results as the gold standard and defining ''failure'' to see as identifying 1, 2, 3, or all 4 letters incorrectly out of 4 trials. The minimum number of iPod trials necessary to maintain high accuracy was determined by defining a ''failure'' as getting the first, first 2, first 3, or all trial letters incorrect. In 13 subjects, the time necessary to perform the testing was determined. RESULTS: Forty-six subjects had an ETDRS Snellen equivalent VA ‡20/40; 45 had a VA <20/40 and ‡20/200; and 13 had a VA <20/200. The mean ± SD testing time for the 3 groups was 43 ± 13, 60 ± 15, and 72 ± 25 seconds, respectively. The highest sensitivity and specificity combination was observed when a ''failure'' was defined as getting all letters incorrect for both the 20/40 (sensitivity [ 98.3%/specificity [ 93.5%) and 20/200 (sensitivity/specificity both 92.3%) cutoffs. CONCLUSIONS: An iPod application requiring about a 1-minute testing time provides an objective, portable, rapid, and low-cost method to determine approximate VA, allowing VA testing to be performed efficiently in large surveys and other settings where approximate VA should be measured. [ABSTRACT FROM AUTHOR]

PURPOSE: To develop and validate an associative model using pupillography that best discriminates those with and without glaucoma. DESIGN: A prospective case-control study. METHODS: We enrolled 148 patients with glaucoma (mean age 67 ± 11) and 71 controls (mean age 60 ± 10) in a clinical setting. This prototype pupillometer is designed to record and analyze pupillary responses at multiple, controlled stimulus intensities while using varied stimulus patterns and colors. We evaluated three approaches: (1) comparing the responses between the two eyes; (2) comparing responses to stimuli between the superonasal and inferonasal fields within each eye; and (3) calculating the absolute pupil response of each individual eye. Associative models were developed using stepwise regression or forward selection with Akaike information criterion and validated by fivefold crossvalidation. We assessed the associative model using sensitivity, specificity and the area-under-the-receiver operating characteristic curve. RESULTS: Persons with glaucoma had more asymmetric pupil responses in the two eyes (P < 0.001); between superonasal and inferonasal visual field within the same eye (P = 0.014); and smaller amplitudes, slower velocities and longer latencies of pupil responses compared to controls (all P < 0.001). A model including age and these three components resulted in an area-under-thereceiver operating characteristic curve of 0.87 (95% CI 0.83 to 0.92) with 80% sensitivity and specificity in detecting glaucoma. This result remained robust after cross-validation. CONCLUSIONS: Using pupillography, we were able to discriminate among persons with glaucoma and those with normal eye examinations. With refinement, pupil testing may provide a simple approach for glaucoma screening. [ABSTRACT FROM AUTHOR]