Prevalence and characteristics of myopic retinopathy in an adult Chinese American population: The Chinese American Eye Study

Program Number: 3615 Poster Board Number: A0064 Presentation Time: 3:45 PM–5:30 PM Prevalence and characteristics of myopic retinopathy in an adult Chinese American population: The Chinese American Eye Study Rohit Varma1, Stacy M. Meuer2, Ronald Klein2, Shuang Wu1. 1Ophthalmology & Visual Sciences, Illinois Eye & Ear Infirmary, Chicago, IL; 2Ophthalmology and Visual Sciences, University of Wisconsin at Madison, Madison, WI. 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 populationbased 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 ageor 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. Commercial Relationships: Rohit Varma, None; Stacy M. Meuer, None; Ronald Klein, None; Shuang Wu, None Support: NIH Grant EY-017337 and Research to Prevent Blindness, NY Program Number: 3616 Poster Board Number: A0065 Presentation Time: 3:45 PM–5:30 PM Retinal pathology in highly myopic eyes: ZOC-BHVI High Myopia Study linxing chen1, Brien A. Holden2, Mingguang He1. 1Zhongshan Ophthalmic Center, Guangzhou, China; 2Brien Holden Vision Institute, Sydney, ACT, Australia. Purpose: High myopia is a major cause of blindness and vision impairment. This study was initiated to evaluate the occurrence of retinal pathology in highly myopic eyes and its impact on visual impairment. Methods: Nine hundred and seventeen participants aged between 7 to 70 years with myopia ≥ -6.00 D in both eyes were recruited from the Zhongshan Ophthalmic Centre clinic for this ZOC-BHVI High Myopia Study. The mean age of participants was 22.1 ± 12.5 years. Exclusion criteria included any systemic or ocular conditions including syndromic high myopia, previous ocular surgery, optical or therapeutic treatment for myopia. Ocular parameters measured in both eyes were: cycloplegic autorefraction, subjective refraction, best corrected visual acuity (BCVA), and axial length (AL) using partial coherence interferometry. Retinal findings were confirmed by slit lamp fundus examination, using 3-mirror fundus lens, and recorded as A. normal; B. abnormal (categories: a. retinal break; b. macular oedema; c. posterior staphyloma; d. retinal detachment). Vision was classified as: Normal Vision (≥ 1.0); Mild Vision Impairment (<1.0 to <0.3); Moderate Vision Impairment (0.3 to ≥0.1); Severe Visual Impairment (<0.1 to ≥0.05) and Blindness (<0.05). Proportion of retinal pathology among the eyes by the categories of age group, spherical equivalent and axial length was calculated. Results: Data from 1686 eyes (843 participants; 442 female) were analysed. The mean spherical equivalent (SE) was -9.30 ± 2.9 D (range: -6.00 to -29.80 D); axial length 27.2 mm ± 1.4 (range 23.8 to 31.8 mm). Myopic retinal pathology was seen in 13.3% (224 eyes). The prevalence of retinal pathology ranged from 5% for age <15 years to 51% for those up to 55 years; 6% for ALs up to 24 mm up to 54% for 32 mm; 5% for -6 D of myopia to up to 65% for -39 D (see Figure1). Proportions of vision impairment among the eyes with retinal pathology were: no VI, 57.0%; mild VI, 40.4%; moderate VI, 2.3% and 0.4% were blind. Multiple logistic regression with robust estimation of variance indicated that age and axial length were the most powerful associates for retinal pathology Conclusions: The prevalence of retinal pathology increases with increasing age, axial length and refractive error. Retinal pathology may be present in eyes with high myopia even when there is no, or only mild vision impairment Commercial Relationships: linxing chen, None; Brien A. Holden, None; Mingguang He, None Support: Australian Government Cooperative Research Centres Grant Scheme