Retinal vein occlusion is a blockage of the small veins that carry blood away from the retina. The retina is the layer of tissue at the back of the inner eye that converts light images to nerve signals and sends them to the brain.
Retinal vein occlusion is most often caused by hardening of the arteries (atherosclerosis) and the formation of a blood clot.
Blockage of smaller veins (branch veins or BRVO) in the retina often occurs in places where retinal arteries that have been thickened or hardened by atherosclerosis cross over and place pressure on a retinal vein.
Risk factors for retinal vein occlusion include:
The risk of these disorders increases with age, therefore retinal vein occlusion most often affects older people.
Blockage of retinal veins may cause other eye problems, including:
Symptoms include sudden blurring or vision loss in all or part of one eye.
Tests to evaluate for vein occlusion include:
Other tests may include:
The health care provider will closely monitor any blockage for several months. It may take 3 or more months for harmful effects such as glaucoma to develop after the occlusion.
Many people will regain vision, even without treatment. However, vision rarely returns to normal. There is no way to reverse or open the blockage.
You may need treatment to prevent another blockage from forming in the same or the other eye.
Treatment for the complications of retinal vein occlusion may include:
The outcome varies. People with retinal vein occlusion often regain useful vision.
It is important to properly manage conditions such as macular edema and glaucoma. However, having either of these complications is more likely to lead to a poor outcome.
Complications may include:
Call your provider if you have sudden blurring or vision loss.
Retinal vein occlusion is a sign of a general blood vessel (vascular) disease. Measures used to prevent other blood vessel diseases may decrease the risk of retinal vein occlusion.
These measures include:
Aspirin or other blood thinners may help prevent blockages in the other eye.
Controlling diabetes may help prevent retinal vein occlusion.
Reviewed By: Franklin W. Lusby, MD, ophthalmologist, Lusby Vision Institute, La Jolla, CA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.