Children's Ocular Components and Age, Gender, and Ethnicity

Purpose. This cross-sectional report includes ocular component data as a function of age, gender, and ethnicity from the Collaborative Longitudinal Evaluation of Ethnicity and Refractive Error (CLEERE) Study. Methods. The ocular components of 4881 school-aged children were examined using cycloplegic autorefraction (refractive error), keratometry (corneal curvature), ultrasonography (axial dimensions), and videophakometry (lens curvature). Results. The average age (+/- SD) was 8.8 +/- 2.3 years, and 2457 were girls (50.3%). Sixteen percent were African-American, 14.8% were Asian, 22.9% were Hispanic, 11.6% were Native American, and 34.9% were White. More myopic/less hyperopic refractive error was associated with greater age, especially in Asians, less in Whites and African Americans. Corneal power varied slightly with age, with girls showing a greater mean corneal power. Native-American children had greater corneal toricity with a markedly flatter horizontal corneal power. Anterior chambers were longer with age, and boys had deeper anterior chambers. Native-American children had the shallowest anterior chambers and Whites the deepest. Girls had higher Gullstrand and calculated lens powers than boys. Boys had longer vitreous chambers and axial lengths, and both were longer with age. Native Americans had the longest vitreous chambers and Whites the shortest. Conclusions. Most ocular components showed little clinically meaningful variation by ethnicity. The shallower anterior chambers and deeper vitreous chambers of Native-American children appeared to be offset by flatter corneas. The relatively deeper anterior chambers and shallower vitreous chambers of White children appeared to be offset by steeper corneas. Asian children had more myopic spherical equivalent refractive errors, but for a given refractive error the ocular parameters of Asian children were moderate in value compared with those of other ethnic groups. Asian children may develop longer, myopic eyes more often than other ethnic groups, but the eyes of Asian emmetropes do not appear to be innately longer. (Optom Vis Sci 2009;86:918-935)