What is retinal artery occlusion?
Definition Retinal artery occlusion refers to the closure of the central retinal artery and usually results in complete loss of vision in one eye. Occlusion of its branches causes loss of vision in only a portion of the field of vision. Description Retinal artery occlusion (RAO) occurs when the central retinal artery, the main source of blood supply to the retina, or one of its branches becomes blocked. Causes and symptoms The main causes of RAO are the following: • embolism (the sudden obstruction of a blood vessel by a blood clot) • atherosclerotic disease that results in the progressive narrowing of the arteries over time • endarteritis (the chronic inflammation of the inner layer of arteries) • angiospasm (a spasmodic contraction of a blood vessel with increase in blood pressure) The most common symptom of RAO is an acute, painless loss of vision in one eye. The degree of loss depends on the location of the occlusion. If the occlusion occurs in the central artery of the retina, dam
