Branch Retinal Vein Occlusions

What is Branch Retinal Vein Occlusions?

Retinal vein occlusions occur when there is a blockage of veins carrying blood with needed oxygen and nutrients to the nerve cells in the retina. A blockage in the retina’s main vein is referred to as a central retinal vein occlusion (CRVO), while a blockage in a smaller vein is called a branch retinal vein occlusion (BRVO).


Most BRVOs occur at an arteriovenous crossing—an intersection between a retinal artery and vein. These vessels share a common sheath, so when the artery loses flexibility, as with atherosclerosis (hardening of the arteries), the vein is compressed.


BRVO causes a sudden, painless loss of vision. If the affected area is not in the center of the eye, It can go unnoticed with no symptoms. In rare cases of an undetected vein occlusion, visual floaters from a vitreous hemorrhage can be the main symptom.