Central Retinal Artery Occlusion (CRAO)
CRAO usually occurs in people between the ages of 50 and 70. the most common medical problem associated with CRAo is arteriosclerosis, hardening of the arteries. Carotid artery disease is found in almost half the people with CRAO.
The most common cause of CRAO is a thrombosis, an abnormal blood clot formation. Sometimes CRAO is caused by an embolus, a clot that breaks off from another area of the body and is carried to the retina by the bloodstream.
CRAO blocks the central artery in the retina. The first sign of CRAO is a sudden an painless loss of vision that leaves you barely able to count fingers or determine light from dark.
Loss of vision can be permanent without immediate treatment. Irreversible retinal damage occurs after 90 minutes, but even 24 hours after symptoms begin, vision may still be saved. The goal of emergency treatment is to restore retinal blood flow. After emergency treatment, the patient should have a thorough medical evaluation.