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Objective: To determine the prevalence, characteristics, and risk factors for myopic retinopathy in a rural population in Northern China. Methods: The Handan Eye Study is a population based study of eye disease in rural Chinese individuals 30 years or older. Eligible residents underwent a detailed ophthalmic examination including standardized visual acuity tests and retinal photography after pupil dilation. Myopic retinopathy was defined to include signs of staphyloma, lacquer cracks, Fuchs spot, and myopic chorioretinal atrophy. Results: Of the 6830 participants, 6603 (96.7%) had gradable photographs in at least 1 eye for assessment of myopic retinopathy. The mean (SD) age was 51.9 (11.8) years. Myopic retinopathy was observed in 60 participants (84 eyes), a person-specific prevalence of 0.9% (95% confidence interval, 0.7%-1.1%). Twenty-four (40.0%) had bilateral disease. Higher myopic retinopathy prevalence was associated with older age (P<.001) and increasing myopic spherical equivalent refractive error (P<.001). Mean (SD) spherical equivalent refraction was -12.3 (6.1) diopters for eyes with myopic retinopathy compared with -1.6 (1.6) diopters in myopic eyes without myopic retinopathy (P<.001). Bilateral blindness or low vision as defined by best-corrected visual acuity was present in 14 participants (24.6%) with myopic retinopathy. Staphyloma was the most frequent myopic retinopathy sign (86.9%), followed by chorioretinal atrophy (56.0%), lacquer cracks (36.9%), and Fuchs spot (14.3%). Conclusions: Myopic retinopathy was detected in 0.9% of rural Chinese individuals 30 years or older. The prevalence of myopic retinopathy was lower than that in the Beijing Eye Study but was similar to white individuals of similar age in the Australian Blue Mountains Eye Study. [ABSTRACT FROM AUTHOR]

Objectives: To describe the measurement of anterior chamber area and anterior chamber volume by anteriorsegment optical coherence tomography and to investigate the association of these parameters with the presence of narrow angles. Methods: This was a cross-sectional study of subjects aged at least 50 years without ophthalmic symptoms recruited from a community clinic. All participants underwent standardized ocular examination and anterior-segment optical coherence tomography. Customized software was used to measure anterior chamber area (cross-sectional area bounded by the corneal endothelium, anterior surface of iris, and lens within the pupil) and anterior chamber volume (calculated by rotating the anterior chamber area 360° around a vertical axis through the midpoint of the anterior chamber area). An eye was considered to have narrow angles if the posterior pigmented trabecular meshwork was not visible for at least 180° on gonioscopy with the eye in the primary position. Results: A total of 1922 subjects were included in the final analyses, 317 (16.5%) of whom had narrow angles. Mean anterior chamber area (15.6 vs 21.1mm2; P<.001) and anterior chamber volume (97.6 vs 142.1 mm3; P<.001) were smaller in eyes with narrow angles compared with those in eyes without narrow angles. After adjusting for age, sex, anterior chamber depth, axial length, and pupil size, smaller anterior chamber area (odds ratio, 53.2; 95% confidence interval, 27.1-104.5) and anterior chamber volume (odds ratio, 40.2; 95% confidence interval, 21.5-75.2) were significantly associated with the presence of narrow angles. Conclusion: Smaller anterior chamber area and anterior chamber volume were independently associated with narrow angles in Singaporeans, even after controlling for other known ocular risk factors. [ABSTRACT FROM AUTHOR]

Objective: To assess the ability of high-definition optical coherence tomography (HD-OCT) to image the anterior chamber angle. Methods: Forty-five consecutive subjects with phakic eyes underwent gonioscopy and anterior chamber angle imaging with HD-OCT adapted with a 60-diopter aspheric lens mounted over the imaging aperture. The patients' fixation was directed to the side using an external fixation light, and scans were taken of the temporal and nasal quadrants. The visibility of angle structures was assessed and the diagnosis of angle closure using HD-OCT was compared with that of gonioscopy. Results: The majority of subjects were Chinese (91.1%) and female (62.2%). Cross-sectional HD-OCT allowed in vivo visualization of the scleral spur in 71 of 90 quadrants (78.9%) and the termination of the Descemet membrane (Schwalbe line) in 84 of 90 quadrants (93.3%). It was possible to image the trabecular mesh work in 56 quadrants (62.2%). Angle closure was observed in 17 eyes with gonioscopy and 12 eyes with HD-OCT (P=.12, McNemar test). The 2 modalities showed good agreement for angle closure diagnosis by quadrant (=0.65). Conclusion: The adapted HD-OCT provided magnified views of the anterior chamber angle and allowed visualization of the Schwalbe line and trabecular meshwork in most eyes. [ABSTRACT FROM AUTHOR]