A stroke, affecting the eye, also called retinal occlusion, is a blockage in the blood vessels of the retina. The blockage is caused by a blood clot or occlusion (tightening or closing) of the blood vessels or accumulation of cholesterol in the blood vessels.
There are a few different types of strokes involving the eyes, depending on whether they affect the veins or the arteries. The veins are blood vessels that bring blood towards the heart. The arteries are blood vessels which carry blood from the heart.
- Peripheral, branch retinal vein occlusion (BRVO) is an occlusion of the small veins of the retina.
- Peripheral, branch veinous occlusion (BRAO) is a blockage of the small arteries in the retina.
- Central retinal veinous occlusion (CRVO) is a blockage of the main vein of the retina.
- Central retinal arterial occlusion (CRAO) is a blockage of the central artery of the retina.
The most common symptom of a stroke involving the eye is a sudden, painless loss of vision. It can affect one eye, in cases of CRAO and CRVO or can affect part of one eye, in cases of BRAO and BRVO. Other symptoms include:
- Loss of peripheral vision
- Deformation of the voice
- Blind spots
Without immediate treatment, vision loss can be permanent.
Medication treatment can be tried. Those procedures should be implemented in a few hours after the symptoms show up to be useful. The procedures include:
• Breathing in an oxygen mixture. This treatment makes arteries of the retina wider.
• Removal of some fluid from the eye, so that the clot can move away from the retina.
Some patients regain their vision after a stroke, even though it is frequently not as good as it was before. Vision loss can also be permanent.