The retina -- the light sensitive tissue in the back of the eye -- includes arteries that bring blood to the eye, and veins that take blood back to the heart.

In a retinal occlusion, one of these vessels becomes blocked. Because the blockage interrupts circulation of blood to the retinal cells, vascular occlusions can cause blindness.

In retinal artery occlusion, a blockage occurs in an artery that brings blood to the retina.

In retinal vein occlusion, a blockage occurs in one of the veins that takes blood from the retina back to the heart. Retinal vein occlusion is the second leading cause of blindness after diabetic retinopathy.

Retinal vein occlusion can occur at the optic nerve (this kind of occlusion is referred to as a central retinal vein occlusion). The blockage can also happen at a branch of the vein, which is called a branch retinal vein occlusion.

Sudden loss of sight or blurry vision can be a symptom of retinal occlusion.

Retinal occlusions are more likely to occur in patients with atherosclerosis, diabetes, high blood pressure, and glaucoma.

Treatments for Retinal Occlusion

No treatments exist to clear the blocked vein or artery. In many instances, some vision will return without treatment.

Retinal occlusions can lead to complications including macular edema and glaucoma. Treatments to minimize the complications of retinal occlusion include:

• Anti-vascular endothelial growth factor (anti-VEGF) medications
• Laser treatment to minimize glaucoma complications
• Focal laser therapy to treat macular edema

Duke Eye Center treats retinal vein occlusions and retinal artery occlusions at locations near Durham, Raleigh, Cary, and many other areas of North Carolina.