Central retinal venous blocks occur when there is a congestion to blood flow and an increase in backpressure on the central retinal vein. It causes variable degree of visual loss and can be easily diagnosed by a retinal examination. It is commonly seen in hypertensives and diabetics. Some times it can be seen in people with clotting abnormalities also.

Common symptoms are sudden onset blurring of vision and some times may present with severe glaucoma.

Evaluations are done to see if there is retinal ischemia or edema at the macula (central retina) A fluorescein angiography and OCT are usually done to look for these. Management is by laser photocoagulation of ischemic areas or by intravitreal injections.

Some cases of central retinal vein occlusions are treated by surgical methods including radial optic neurotomy.