Retinal Vein Occlusions (CRVO & BRVO)
Blockage of a retinal vein that leads to retinal hemorrhages and macular edema. Requires timely ocular treatment and systemic cardiovascular evaluation.
What Is a Retinal Vein Occlusion?
Blood drains from the retina through veins that converge into the central retinal vein at the optic nerve. When one of these veins becomes blocked, blood cannot drain normally, pressure inside the vessels rises, and hemorrhages and fluid leakage occur in the retina.
When the blockage occurs in the main trunk, it is called Central Retinal Vein Occlusion (CRVO). When it affects a smaller branch—usually where a stiffened artery crosses over a vein—it is called Branch Retinal Vein Occlusion (BRVO). CRVO generally affects vision more diffusely.
Risk Factors & Symptoms
Retinal vein occlusion is more frequent after age 50 and is strongly associated with high blood pressure, diabetes, high cholesterol, glaucoma, and—especially in younger patients—blood clotting disorders.
The classic symptom is sudden, painless vision loss or blurring in one eye, affecting either the entire visual field or just the upper or lower half.
Diagnosis & Treatment
Diagnosis is made by dilated retinal examination. OCT quantifies macular edema and guides follow-up, while angiography evaluates areas of poor capillary perfusion (ischemia).
The primary goal of ocular therapy is resolving macular edema, which is responsible for decreased central vision. Intravitreal anti-VEGF injections are the first-line treatment, and sustained-release corticosteroid implants are an effective option in selected cases. When significant ischemia or abnormal new vessels are present, retinal laser photocoagulation prevents complications such as neovascular glaucoma.
This condition is part of the Retina & Intravitreal Injections specialty.
Frequently Asked Questions
Can a retinal vein occlusion happen in the other eye?
There is a risk, especially if systemic risk factors are not controlled. Managing blood pressure, blood sugar, and cholesterol is the most effective protection.
How soon after noticing symptoms should I see an ophthalmologist?
As soon as possible. Any sudden, painless drop in vision should be evaluated promptly by an ophthalmologist.