Retinal Artery Occlusions Strokes In the Eye

By John Choi, MD

The retina is the inner lining of our eyeballs. It has vision machinery such as photoreceptors and is the vision “engine”. This engine needs “gas”, the blood supplied by arteries. When one of these arteries is clogged (occluded), the gas supply cuts out. The engine stops working, and vision gets worse.

Blood to the retina mostly comes through the central retinal artery. The central retinal artery is like a tree trunk which divides into smaller branches, the branch retinal arteries. A central retinal artery occlusion chokes off the main blood supply to the retina and can severely damage vision. A branch retinal artery occlusion affects vision to varying degrees depending on the size of the branch and its location in the eye.

What Causes A Retinal Artery Occlusion?

Usually a clot in the artery. The most common type of clot comes from plaques of atherosclerosis in the neck carotid arteries or the heart. A piece of plaque breaks off and travels through the blood vessels until it lodges in a retinal artery. People with cardiovascular risk factors such as hypertension, high cholesterol, or smoking are at higher risk of developing retinal artery occlusions in addition to heart attacks and strokes. Because strokes are usually from clots in brain arteries, a retinal artery occlusion is often called a “stroke in the eye”.

What Are the Symptoms Of A Retinal Artery Occlusion?

Sudden painless loss of part or all of the vision. This may be hard to tell if it's mild because the other unaffected eye is covering for the bad eye. Often the vision loss is noticed only when the good eye is closed.

How Do You Diagnose A Retinal Artery Occlusion?

Your eye doctor will review your medical history, keeping in mind any cardiovascular risk factors or disease. An eye exam will reveal changes from the retinal artery occlusion. The eye doctor will refer you to a Retina specialist, who is an expert in this disease. The Retina specialist will do a more advanced examination and eye pictures to confirm the diagnosis.

How Do You Treat A Retinal Artery Occlusion?

Unfortunately, there is currently no good treatment. Vision loss is usually permanent although sometimes it can improve. Therapy is focused on managing with the primary care provider and cardiologist the underlying cardiovascular conditions which caused it to prevent more retinal artery occlusions, strokes, and heart attacks.