Disc vascularity in Down's syndrome.

Ocular fundus photographs of 100 eyes were obtained from an institutionalized population of patients with Down's Syndrome (66 males, 34 females). The vascularity of the optic nerve head was assessed in each photograph by counting the number of arterioles, venules, and fine vessels crossing the disc margin. The results of this analysis were compared to similar data obtained from 100 ocular fundus photographs of normal patients and show that there are more large vessels crossing the disc margin in those with Down's Syndrome.