Morphologic Predictive Factors for the Development of Optic Disc Hemorrhages in Glaucoma

Abstract

Abstract: : Purpose: To evaluate which optic disc parameters are predictive factors for the development of disc hemorrhages in chronic open-angle glaucoma. Methods: The prospective comparative clinical observational study included 432 eyes of 281 Caucasian patients with chronic open-angle glaucoma. Mean follow-up time was 38.8 months (median 31.5). The whole study group was differentiated into eyes with an optic disc hemorrhage during the follow-up period ("hemorrhagic group") (n=38; 8.8%), eyes without disc hemorrhages and with neuroretinal rim loss as sign of progression of glaucoma ("rim loss group") (n=42; 9.7%), and eyes with neither disc hemorrhages nor neuroretinal rim loss ("stable group") (n=352; 81.5%). All patients underwent repeated qualitative and morphometric evaluation of color stereo optic disc photographs. Results: At baseline of the study, neuroretinal rim area was significantly (P<0.03) smaller and beta zone of parapapillary atrophy (temporal lower sector) was significantly (P<0.03) larger in the hemorrhagic group than in the stable group. Both study groups did not vary significantly (P≷0.05) in optic disc size and shape, optic cup depth, alpha zone of parapapillary atrophy, and retinal vessel diameter. In multivariate analysis, neuroretinal rim area was the only significant predictor of hemorrhages. The hemorrhagic group and the rim loss group did not differ significantly (P≷0.05) in any optic disc parameter measured. Conclusion: In chronic open-angle glaucoma, morphologic predictive factors for the development of disc hemorrhages are small size of neuroretinal rim and, possibly, large area of parapapillary beta zone. Development of disc hemorrhages is independent of optic disc size and shape, size of alpha zone of parapapillary atrophy, retinal vessel diameter, and optic cup depth. Eyes with eventual development of disc hemorrhages and eyes with eventual progressive rim loss without observed disc hemorrhages do not differ markedly in the optic nerve head appearance.

Keywords: 498 optic disc • 484 nerve fiber layer • 453 lamina cribrosa