CRAO, or Central Retinal Artery Occlusion is a condition in which there is irreversible damage to the retinal rods and cones, cells which process light into electrical stimulus for the brain to understand, as a result of complete stoppage of blood flow. Within 6 hours, the retina becomes damaged, if immediate measures are not taken to prevent full stoppage of blood supply.
The cause usually is a problem with the heart or blood vessels supplying blood to the eye. Factors which can increase the risk for CRAO are pregnancy, high cholesterol, obesity, diabetes, hypertension, and some medicines like oral contraceptive pills. The cardiologist has to enquire into great detail for such history and investigate accordingly. This is to prevent such episode from occurring in the other eye or brain.