Occlusions of the veins in the retina can cause significant damage to the health of the retina. Prompt diagnosis and evaluation for complications of vein occlusions is critical to decrease the chances of further loss of vision.
WHAT IS A RETINAL VEIN OCCLUSION?
Veins take blood back to the heart whereas arteries take blood from the heart to the different parts of your body including the eyes. A retinal vein occlusion happens when you have a blockage of either the main vein of the retina or one of its branches. It is considered a hemorrhagic stroke of the retina as the veins start to bleed into the retina. It usually causes a painless, unilateral loss of vision.
WHAT ARE THE RISK FACTORS FOR A RETINAL VEIN OCCLUSION?
A retinal vein occlusion most commonly occurs secondary to the changes that happen in the blood vessel walls of the arteries. As the blood vessel wall of the arteries thickens, it presses on the veins which causes changes in the blood flow within your veins which lead to blood clots (thrombosis) that block the venous flow.
Risk factors include atherosclerosis, hypertension, swelling of the nerve of the eye (optic disc edema), changes within the nerve of the eye (optic disc drusen), blood diseases that increase risk of clotting (ex: lymphoma, leukemia, polycythemia, sickle cell disease, antiphospholipid syndrome, multiple myeloma, Waldenstrom macroglobulinemia, cryoglobulinemia, hyperhomocystinemia, activated protein C resistance), drugs (ex: diuretics, oral contraceptives), inflammatory diseases and more.
WHAT ARE THE TREATMENTS FOR A RETINAL VEIN OCCLUSION?
The treatment is dependent on a detailed evaluation by your eye specialist and on the results of the recommended testing, as a wide variety of diseases can cause a retinal vein occlusion. In addition to treating the systemic disease, your eye doctor will follow you closely as you can have growth of abnormal blood vessels (neovascularization) on the retina and on the iris that can bleed and significantly affect vision. You may require treatment with Laser if significant neovascularization is detected in order to decrease your risk of bleeding in the eye.
If you develop swelling in the central part of the retina (macular edema), your doctor may consider treating you with intravitreal injections of medications (anti-VEGF or steroid) in order to decrease the swelling and improve vision.
About 10% of patients can develop a retinal vein occlusion in the other eye.