Comparison of Anterior Segment Parameters among Koreans, Chinese, and White Persons.

PURPOSE: To evaluate anterior segment (AS) parameters obtained by AS OCT within an urban Korean population and to compare them with measurements seen in Chinese and white participants. DESIGN: Prospective, cross-sectional, clinic-based study. PARTICIPANTS: Three gender- and age-matched cohorts of Korean, Chinese, and white participants recruited from general ophthalmology clinics in urban academic hospital settings. METHODS: Anterior segment OCT (Visante OCT; Carl Zeiss Meditec, Dublin, CA) was used to image the AS of all participants. Customized software was used to calculate AS parameters. MAIN OUTCOME MEASURES: Five angle parameters (AOD500, AOD750, TISA500, TISA750, ARA), 5 iris parameters (IT750, IT2000, ITCM, Iarea, Icurv), and 5 anterior chamber parameters (ACD, ACW, ACA, ACV, LV) were compared. Anterior vault (AV), relative AV, and relative LV were also calculated. These parameters were compared across all cohorts using a Kruskal-Wallis test. General linear models were built to assess pairwise comparison between Korean and Chinese and between Korean and white cohorts. Two-sided P values less than 0.05 were considered statistically significant. We also considered Bonferroni correction to control family-wise type 1 error (ɑFW = 0.05 / 18 = 0.003). RESULTS: The study included 132, 124, and 112 participants in the Korean, Chinese, and white cohorts, respectively. Korean participants showed AS parameters similar to those of Chinese participants, with the exception of having a smaller average ACW and a larger average IT2000. Compared with white persons, Koreans showed smaller angle parameters (trabecular-iris space area measured at 500 µm and 750 µm from the SS and angle recess area), anterior chamber parameters (ACD, ACW, ACA, ACV), and thicker irises (iris thickness measured at 750 µm and 2000 µm from the SS, maximum IT at the middle one third of the iris). The Korean cohort also was noted to show a smaller average LV compared with both Chinese and white cohorts. CONCLUSIONS: The Korean cohort demonstrated smaller average LV and relative LV.