The retinal artery carries oxygen rich blood to the retina. When a blockage occurs in the main artery or one of its branches, the retinal cells begin to suffocate from a lack of oxygen and can cause significant and permanent vision loss. Retinal artery occlusions generally present as sudden and painless vision loss that can involve the peripheral and/or central vision depending on the location of the blockage.
Before this happens, some individuals experience episodes of vision loss. The cause of the blockage is most commonly a clot or embolus (floating blood clot or debris in the bloodstream) from the neck or the heart. This clot blocks blood flow to the retina and individuals with high blood pressure, diabetes, or carotid artery disease are at higher risk.
Artery occlusions can be diagnosed during your eye exam. A cardiovascular evaluation may be recommended since blood supply can also be affected in other parts of the body (including the heart and brain). Treatment options are limited, but some patients retain reasonably good vision.