Retinal Artery Occlusion

Retinal artery occlusion is a relatively uncommon eye condition that may cause severe vision loss. There are two main types of retinal artery occlusion: branch retinal artery occlusion and central retinal artery occlusion.

This photograph shows the acute phase of a central retinal artery occlusion. Most of the retina you see in this picture is yellow-white and swollen because it is cut off from its blood supply. The red circle in the center represents the "cherry red spot" in the center of the macula. This spot is red because the center of the retina is very thin and allows you to see the blood flow through the choroid layer below the retina. The other finger-shaped red area is normal retinal tissue being supplied blood from a cilioretinal artery. If you look closely you will see that the artery supplying this area is not coming off the central stalk. This is called a cilioretinal artery because instead of being a branch off the central retinal artery, it is a branch off the ciliary artery, which typically supplies the outer layers of the eyeball. Approximately one in five people have such a secondary circulation to the retina. In the case of this patient who has a central retinal artery occlusion, this secondary circulation has saved a small piece of retina from the damage caused by the central artery blockage.

While there are no proven medical or surgical techniques for treating retinal artery occlusions, the presence of these disorders indicates an underlying systemic cause that must be ascertained with adequate bloodwork and body imaging, and thus correctly treated. If, for instance, the disorder is caused by a disease called giant cell temporal arteritis, immediate intravenous steroid is required to lessen the chance of vision loss in the fellow eye. The only local eye treatment that may be used in artery occlusions is laser or intravitreal anti-vascular endolthelial growth factor injection if abnormal blood vessels (neovascularization) develop later on and cause complications such as glaucoma.