Central retinal artery occlusion.

Central retinal artery occlusion is characterized by sudden, painless visual loss due to blockage of retinal blood flow. It has been reported in all age groups including children but is most frequent in the sixth decade. Both thrombosis and embolism have been suggested as possible mechanisms. The emergency treatment includes intravenous acetazolamide, digital ocular massage, and inhalation of 5% carbon dioxide -- 95% oxygen for ten minutes. Following emergency treatment, immediate ophthalmologic referral and consultation is required. Comprehensive medical evaluation should be initiated to exclude systemic vascular disease.