Central retinal artery occlusion

An occlusion is a blockage that occurs in a blood vessel as a result of debris in the bloodstream, inflammation, or high blood pressure. Within the arteries of the retina, occlusions most often occur due to clots that dislodge from another vessel in the body and flow into the smaller artery of the retina. A blockage may occur in the main artery of the retina or in any of the smaller branch arteries.

Retinal artery occlusions are more serious than retinal venous occlusions. When the central retinal artery is blocked, a significant area of the retina will be deprived of oxygen. If the blockage is not removed almost immediately, the affected cells of the retina will die. Retinal artery occlusions occur suddenly, causing immediate and drastic decreased vision in one eye.

Occasionally, a blockage in the central retinal artery may be removed before the affected cells of the retina die. This is rare, because the ophthalmologist would have to free it to move out of the central artery into a larger vessel almost immediately. 

Once a central retinal artery occlusion occurs, and the affected cells die, there is no way to restore the vision that has been lost. However, there are ways to lessen the chance that a future occlusion will occur. Most people who have a central retinal artery occlusion have high blood pressure, high cholesterol, or some form of vessel disease. When proper steps are taken to control blood pressure, cholesterol, and or blood sugar, the occurrence of another occlusion is much less likely.