Central retinal artery occlusion is the blockage of blood to the retina of one eye. It usually causes sudden loss of eyesight in one eye. You are higher risk if you are older or have high blood pressure, glaucoma, or diabetes. You are also at higher risk if your blood is thicker and stickier than normal.
Central retinal artery occlusion (CRAO) is a form of acute ischemic stroke that causes severe visual loss and is a harbinger of further cerebrovascular and cardiovascular events.
Central retinal vein occlusion is an occlusion of the main retinal vein posterior to the lamina cribrosa of the optic nerve and is typically caused by thrombosis. Central retinal vein occlusion is further divided into two categories: non-ischemic (perfused) and ischemic (nonperfused).
Symptoms and Causes Retinal vein occlusion happens when a blood clot blocks the vein. Sometimes it happens because the veins of the eye are too narrow. It is more likely to occur in people with diabetes, and possibly high blood pressure, high cholesterol levels, or other health problems that affect blood flow.
What causes central retinal artery occlusion (CRAO)?Cholesterol is the most common type, but it can also be from calcium, bacteria, or talc from intravenous drug use.This is associated with poorer visual acuity and higher overall morbidity and mortality.More items...•
Diagnosis. The diagnosis is suspected when a patient has acute, painless, severe vision loss. Funduscopy is usually confirmatory. Fluorescein angiography is often done and shows absence of perfusion in the affected artery.
Central retinal vein occlusion, also known as CRVO, is a condition in which the main vein that drains blood from the retina closes off partially or completely. This can cause blurred vision and other problems with the eye.
CRVO is caused by blockage in the main vein that drains the retinal vasculature, whereas a BRVO is caused by a blockage in a smaller vein that drains a portion of the retinal vasculature.
Presentation is with sudden, unilateral blurred vision. In non-ischemic CRVO, the blurring is mild and may be worse on waking and improves during the day. In ischemic CRVO, visual impairment is sudden and severe.
The central retinal artery is typically the first branch of the ophthalmic artery. It runs along the inferior aspect of the optic nerve before piercing the optic nerve sheath 5–15 mm posterior to the globe.
RVO occurs when a blood vessel in the retina becomes blocked, often by a blood clot. When fluid leaks into the macula as a result of the blocked blood vessel, it is called Macular Edema following Retinal Vein Occlusion, or MEfRVO.