Retinal Vein Occlusion
The retina is composed of nerve tissue in the back of the eye that transmits light signals to the brain. Blood vessels in the retina circulate blood to and from the heart. In a retinal vein occlusion, a vein in the retina is blocked and blood flow to the affected area is inadequate. There are two types of occlusions; a central retinal vein occlusion (CRVO) and a branch retinal vein occlusion (BRVO). A blocked vein can cause blood vessels to leak excess blood and fluid into the retina and cause swelling. Hypertension, heart disease, and diabetes all can contribute to retinal vein occlusions.
Symptoms of retinal vein occlusions can vary based of the location and severity of the occlusion. Vision loss or blurred vision can be caused by leakage of fluid into the retina or inadequate blood flow to areas of the retina. Vein occlusions can also cause growth of new blood vessels, neovascularization, and increased eye pressure, so it is important to be seen by a vitreoretinal specialist soon after diagnosis or if you experience symptoms of a vein occlusion.
A combination of dilated exam, fundus photos, fluorescein angiography (FA), and optical coherence tomography (OCT) will allow an ophthalmologist to assess the retinal vein occlusion and severity of swelling. Your ophthalmologist may suggest a visit to your primary care doctor following a retinal vein occlusion for treatment of underlying conditions.
Treatment for a retinal vein occlusion typically involves treating macular edema, a complication following an occlusion, where excess blood and fluid leak into the retina and cause swelling. Treatments for macular edema include anti-vascular-endothelial-growth-factor (anti-VEGF) injections, steroids, or laser treatment. Your physician will help decide which treatment will work best and multiple treatments may be necessary to improve or maintain vision.