Racial Differences in Optic Disc Topography: Baseline Results From the Confocal Scanning Laser OphthalmoscopyAncillary Study to the Ocular Hypertension Treatment Study

OBJECTIVE To examine racial differences in optic disc topography among ocularhypertensive participants in the Ocular Hypertension Treatment Study. METHODS Four hundred thirty-nine participants from 7 Ocular Hypertension TreatmentStudy centers who had good-quality baseline images obtained using a quantitative3-dimensional confocal scanning laser ophthalmoscope, the Heidelberg RetinaTomograph (Heidelberg Engineering, Dossenheim, Germany), were included inthis study. The first 10°- or 15°-field of view mean topographic imageacquired was included in all analyses. Differences in Heidelberg Retina Tomographtopographic optic disc parameter measurements by self-identified race wereassessed using a mixed-effects linear model to control for confounders andfor the use of both eyes in the model. RESULTS By self-attribution, 74 (17%) of the 439 participants were of Africanorigin, 329 (75%) were white, 24 (5%) were Hispanic, and 12 (3%) were NativeAmerican, Native Alaskan, Asian, Pacific Islander, or unknown. The AfricanAmerican participants had statistically significantly (P.10). CONCLUSIONS This study demonstrated in a large cohort of subjects with ocular hypertension,that African Americans have significantly larger optic discs, optic cups,neuroretinal rims, and cup-disc ratios than other racial groups. Furthermore,this study found that differences in topographic optic disc parameters betweenAfrican Americans with ocular hypertension and other racial groups are largelyexplained by the larger optic disc area in the African Americans. These resultshighlight the need to consider race and optic disc size when evaluating theappearance of the optic disc in glaucoma.Arch Ophthalmol. 2004;(122):22-28-->