Data regarding the etiology and subsequent course of 54 patients with an occlusion of the central retinal artery included the following: of 44 patients over 40 years of age at the time of the central retinal artery occlusion, eight (18%) had cerebrovascular accidents, but only two patients (5%) had a stroke clearly related to the vessels involving the affected central retinal artery. Five patients (11%) had occlusive disease of the ipsilateral internal carotid artery; two of these had cerebral involvement later or simultaneously. Ten of the older patients had cardiac valvular disease and presumed embolic occlusion of the central retinal artery. Associated medical disorders were common. Of the ten patients under 40 years of age, six occlusions were secondary to atrial myxoma, mitral insufficiency with Marfan's syndrome, polycythemia, hypercoagluopathy, hypertension, and orbital compression. Four had no apparent etiology at onset and were in good health many years later.