The prevalence of optic disc pits and their relationship to glaucoma.

Purpose To determine prevalence and associations of pits of the optic disc in an older population and assess their relationship to open-angle glaucoma. Design Population-based cross-sectional study. Methods The Blue Mountains Eye Study examined 3654 persons (82.4% of permanent residents) aged over 48 years. Stereo-optic disc photographs were graded in a masked fashion. Results Nine pits were found in 7 persons, a population prevalence of 0.19%. Three morphologic subtypes were found. Four peripheral pits were found at the inferior pole. Four central pits were located adjacent to the main vessel trunk. One pit was on the temporal disc margin. Pit prevalence increased with age (beta=0.0879, P=0.0099). It was strongly associated with high-pressure open-angle glaucoma [odds ratio (OR) 29, 95% confidence interval (95CI) 7-127], beta-peripapillary atrophy (OR 7.5, 95CI 2-32), and optic disc hemorrhage (OR 42, 95CI 9-183) after adjusting for age and sex. All peripheral pits were associated with paracentral visual field loss. Conclusions The classically described temporal optic disc pit was the rarest morphologic subtype found in this older population. Optic disc pits were primarily associated with glaucoma and the related signs of optic disc hemorrhage and beta-peripapillary atrophy. The previously reported optic disc pit association with low-tension glaucoma may represent acquisition bias.