What Are the Causes of Central Retinal Vein Occlusion?

Central retinal vein occlusion occurs when something causes a blockage or pressure on the central vein that feeds the retina, which is the light-sensitive tissue in the back of the eye. Blockage or pressure cuts off the blood and oxygen supply to the retina, which causes vision loss. There are a number of conditions that could cause central retinal vein occlusion.

Blood clot

• Blood clots that develop in the central retinal vein or that develop elsewhere in the body and travel through the blood vessels to the central retinal vein are a common cause of central retinal vein occlusion. Doctors classify blood clots in the retinal vein as either ischemic (blocking oxygen) or non-ischemic (not blocking oxygen). Most blood clots are the former type.

Diabetes

• Diabetes tends to cause comorbid ailments of the heart, circulatory system, and eyes, so it is a major risk factor for central retinal vein occlusion. Diabetic patients frequently have high blood pressure, cardiovascular disease, blocked arteries, and vision problems, especially increased pressure in the eye. Any of these conditions related to diabetes can cause central retinal vein occlusion.

Glaucoma

• Glaucoma is a condition where increased pressure in the eye damages the optic nerve. The swelling of the optic nerve can sometimes put pressure on or block the central retinal vein. Whereas central retinal vein occlusion is treatable and often reversible, glaucoma is the second most common cause of blindness in the U.S.

Hardening of the arteries

• Atherosclerosis, or hardening of the arteries, is a condition where plaque forms on the walls of the arteries, creating a blockage. Most of the time, blockages occur in the arteries of the chest, but occasionally blockages can occur in the central retinal vein. Patients with high triglyceride levels, heart disease, or diabetes are at an especially high risk for hardening of the arteries.

High blood pressure

• High blood pressure can cause central retinal vein occlusion because of the increased pressure of the blood traveling through the veins in the eye. Swelling and increased pressure can temporarily block the central retinal vein, causing vision problems.