Optic disc morphology in diabetes mellitus.

Abstract

Diabetes mellitus is a systemic disease affecting multiple tissues throughout the body. This study was performed to evaluate intravitally the diabetic changes of the optic disc. Color photographs of 115 eyes with varying severity of diabetic retinopathy and of 29 normal eyes were morphometrically examined. We found that the size and shape of the optic disc, the neuroretinal rim and the parapapillary atrophy did not differ significantly between the diabetic eyes and the normal eyes. These variables were independent of the degree of diabetic retinopathy. There was a tendency toward decreased visibility of the retinal nerve fiber layer and increased optic disc pallor in the diabetic eyes. The results indicate that the area and form of the optic disc, the neuroretinal rim and parapapillary atrophy are not altered by diabetes mellitus. This is important for the diagnosis of glaucoma in diabetic patients, since glaucoma leads to a decrease of rim area and an enlargement of parapapillary atrophy. The reduced visibility of the retinal nerve fiber layer, the increased optic disc pallor and the unchanged size of the neuroretinal rim and parapapillary atrophy suggest that diabetes mellitus may be associated with nonglaucomatous optic nerve atrophy.