The cup-to-disc ratio and central retinal vein occlusion.

Recent reports have suggested that a small optic cup may contribute to the development of certain optic disc disorders, such as anterior ischemic optic neuropathy. In a masked fashion, the cup-to-disc ratios from the fellow eyes of 55 patients with central retinal vein occlusion (CRVO) were compared with 55 controls to determine whether a similar association could be established for CRVO. Controls came from two population-based surveys, and they were matched to cases for age, race, and sex. The mean cup-to-disc ratios for the CRVO fellow eyes and controls were 0.39 and 0.40, respectively; the distribution of the sizes of the cup-to-disc ratios was nearly identical in the two groups. These results suggested that the cup-to-disc ratio is not a useful predictor of the development of CRVO.