Abstract
Purpose:
To provide estimates of the prevalence and characteristics of myopic retinopathy in a population based sample of adult Chinese Americans.
Methods:
The Chinese-American Eye Study (CHES) is a population-based study in which Chinese-Americans aged 50 years and older residing in 10 contiguous census tract in Monterey Park, CA were invited to undergo a comprehensive eye exam, including subjective and objective refraction, stereoscopic fundus photography of both eyes. Myopic retinopathy was assessed in a masked manner by trained graders. Specifically, myopic retinopathy was defined as the presence of one or more of the following lesions staphyloma, lacquer cracks, patchy or diffused atrophy, intrachoroidal cavitation, tilted optic disc, tessellation, peripapillary atrophy and exudative myopia. Eyes with spherical equivalent ≤ -0.5 diopters and/or with axial length ≥ 24mm were evaluated for myopic retinopathy. One eye (eye with the more myopic refractive error) from each participant was included in this analysis. Frequency distributions stratified by refractive error and axial length were calculated. Differences were assessed using chi square testing.
Results:
Of the 1,590 participants meeting the selection criteria and with gradable fundus photographs, 1,328 participants were graded for myopic retinopathy. The overall prevalence of myopic retinopathy among eyes was 33.7% (95%CI 31.2%-36.2%). The prevalence of specific lesions were Tessellation (32.4%), tilted disc (29.8%), peripapillary atrophy (8.2%), staphyloma (6.3%), diffused atrophy (5.0%), lacquer cracks (2.9%), intrachoroidal cavitation (2.4%), patchy atrophy (1.1%), and exudative myopia (0.2%).The prevalence of myopic retinal changes in persons with mild (≤ -0.5D, > -1D), moderate (≤ -1D, > -6D) and high myopia (≤ -6D) were 17%, 46% and 83% respectively. The prevalence of myopic retinal changes in persons with varying degrees of axial elongation were: <23mm - 11%, ≥ 23.0, <24.5mm - 26%, ≥ 24.5, <26mm - 56%, ≥26mm - 82%. No age- or gender-related differences were observed.
Conclusions:
These data provide the first population-based estimates of myopic retinopathy in Chinese Americans. The prevalence of myopic retinopathy in Chinese Americans is higher than that observed in other East Asian populations.