Retinal Vein Occlusions
The retina has many small veins which all drain into a large central vein in the back of the eye. This central vein carries blood from the retina to the heart. A retinal vein occlusion is a blockage of one of these veins, preventing blood from leaving part or all of the retina. These blockages can lead to damage in the retina by causing blood vessels to leak, close up, or grow where they do not belong. Retinal vein occlusions are common causes of visual loss involving the retina.
There are two types of retinal vein occlusions:
- Central retinal vein occlusion (CRVO) – This is a blockage of the main large vein, called the central retinal vein.
- Branch retinal vein occlusion (BRVO) – This is the blockage of one of the smaller veins that branch into the central retinal vein.
The main symptoms of both central and branch retinal vein occlusion is vision loss or blurry vision. Typically, the disease only affects one eye, but a small percentage of patients can have it in both eyes.
Retinal vein occlusions are common causes of visual loss involving the retina.
Retinal vein occlusions occur most often in people over the age of 50. The most common risk factors include aging, high blood pressure, diabetes, smoking, and glaucoma. In younger patients, blood work may be necessary to look for rarer causes of this condition.
There is no treatment for the actual blockage of the retinal veins. Instead, the complications of the disease—swelling, poor blood flow, and abnormal growth of new blood vessels—are treated. Treatments include laser and/or injections of medication into the eye, depending on the manifestations and severity of the disease. With successful treatment, many patients see their vision improve although full return of vision is not possible in all cases.