Optic disk size in chronic glaucoma: the Beijing eye study.

Purpose To evaluate whether eyes with chronic glaucoma have a larger or smaller optic disk than normal eyes. Design Population-based, cross-sectional cohort study. Methods The study included 4439 subjects out of 5324 subjects invited to participate with an age of 40+ years. Color optic disk photographs (45°) were morphometrically examined. Results After exclusion of aphakic eyes, pseudophakic eyes, and highly myopic eyes, data of 3989 subjects entered the statistical analysis. The mean optic disk area did not vary significantly ( P > .05) between the nonglaucomatous group (2.61 ± 0.50 mm 2 ), eyes with glaucomatous appearance of the optic disk (2.69 ± 0.63 mm 2 ), eyes with glaucomatous optic disks and visual field defects (2.66 ± 0.70 mm 2 ), and eyes with elevated intraocular pressure (2.63 ± 0.49 mm 2 ). Conclusions In adult Chinese, optic disk size may not markedly differ between normal eyes and eyes with chronic glaucoma.