When you think of a stroke, you’re likely thinking of a cerebral stroke, when either a blood vessel in (or around) the brain bursts or when a blood clot prevents blood from getting to the brain.
But have you heard of an eye stroke? “An eye stroke is a term used to describe different conditions causing vision loss due to poor blood flow to the eye,” said Kunyong Xu, MD, clinical assistant professor of ophthalmology at Banner - University Medical Center Tucson. “It can occur when there are blockages in the arteries or veins that supply blood to the retina.”
Retinal Artery Occlusion
One such blockage that can cause an eye stroke is a retinal artery occlusion. “Retinal artery occlusion occurs when the blood flow through the retinal artery – either the central or branch retinal artery – is blocked due to embolism or thrombosis,” explained Dr. Xu. The central retinal artery provides critical blood supply to your inner retina and separates into smaller branches or branch retinal arteries.
- Central retinal artery occlusion: when a blockage or clot in the main artery to the retina prevents blood flow. This is an emergency and should be evaluated by a physician immediately.
- Branch retinal artery occlusion: this occurs when there is a blockage in the smaller arteries in your eye.
How Do I Know if I’m Experiencing a Retinal Artery Occlusion?
If you experience sudden, painless, vision loss – especially if it’s in one eye – this could be a sign that you have a central retinal artery occlusion. “The onset of vision loss from a central retinal artery occlusion is often profound,” said Dr. Xu. “With a branch retinal artery occlusion, patients normally maintain fair to good vision, with only a slight loss of peripheral vision.” The symptoms may last a few seconds to a few minutes, or, the vision loss could be permanent.
Am I at Risk for a Retinal Artery Occlusion?
The risk factors for an eye stroke caused by retinal artery occlusion are similar to those that may cause a cerebral stroke. Any conditions that cause your vascular system to contract can lead to a retinal artery occlusion. “People who have high cholesterol, hypertension, diabetes, collagen vascular disease, heart valve disease, and arrhythmia should be aware that these conditions can cause a retinal artery occlusion,” Dr. Xu explained.
Other conditions that could cause an eye stroke include giant cell arteritis, an autoimmune disorder that causes inflammation of neck, scalp, and/or arm arteries, and hyper-coagulopathies, a disorder where your blood clots more frequently.
Diagnosis and Treatment
The last time you went for an eye exam, did the doctor dilate your eyes? This part of the exam is when a retinal artery occlusion can be detected. When your eye is dilated, the doctor can see more clearly into your eye to detect various diseases or problems with the arteries. If your eye doctor sees something concerning he or she may recommend a fluorescein angiography, during which a dye is injected and then monitored as it flows through the blood vessels in the back of your eye.
When it comes to retinal artery occlusion, your best bet is prevention. “No treatments have been proven successful in treating the vision loss associated with retinal artery occlusion,” said Dr. Xu.
Learn more about how you can take care of one of your most important senses by scheduling a consultation with a Banner Health ophthalmologist.