Central Retinal Vein Occlusion

Central Retinal Vein Occlusion (CRVO) is a serious and potentially sight-threatening eye condition that occurs when the central retinal vein becomes blocked or occluded. The central retinal vein is responsible for draining deoxygenated blood from the retina, the light-sensitive layer of tissue at the back of the eye. When this vein becomes blocked, blood flow to the retina is impaired, leading to retinal hemorrhages, fluid accumulation, and in some cases, significant damage to the retina. CRVO is one of the leading causes of vision loss among adults, particularly those over the age of 50.

CRVO can be classified into two types: non-ischemic and ischemic. Non-ischemic CRVO, also known as the "better" form, involves less severe retinal damage and usually carries a better prognosis. Ischemic CRVO, however, results in reduced blood flow to the retina and is associated with more severe vision loss.

Timely intervention and management of CRVO are essential in preventing further complications, such as macular edema, neovascularization, and glaucoma. With appropriate treatment, many individuals can recover some degree of vision or prevent further vision deterioration.

The exact cause of CRVO is not always clear, but it is primarily associated with several underlying factors that affect blood flow in the eye. The most common cause of CRVO is retinal vein thrombosis—the formation of a blood clot in the retinal vein, which can block or reduce blood flow. Below are the main causes and risk factors associated with this condition:

As individuals age, the risk of CRVO increases significantly. The condition is more common in those over 50 and becomes even more prevalent in individuals aged 70 and older.

One of the most significant risk factors for CRVO is hypertension. High blood pressure causes increased pressure in the blood vessels, which can lead to the narrowing and thickening of the retinal veins, making them more prone to occlusion.

Atherosclerosis, which is the buildup of plaque inside the arteries, is another contributing factor. This condition affects the circulation throughout the body, including the eye, and may increase the risk of blood clot formation in the retinal vein.

Individuals with diabetes, particularly those with poorly controlled blood sugar levels, are at a significantly increased risk of CRVO. Diabetic retinopathy, a condition caused by damage to the blood vessels of the retina, can also predispose individuals to retinal vein occlusion.