Retinal Vein Occlusion

This week’s blog on Retinal Vein Occlusion has been contributed by Dr Hassan Aziz, Consultant Vitreoretinal Surgeon.

What is Retinal Vein Occlusion?

Retinal Vein Occlusion occurs when a retinal vessel is occluded, blocking the drainage of the blood from the retina. This results in the accumulation of blood (retinal hemorrhages) and fluid (macular edema) in the retina and leads to a drop in the visual acuity (clarity of vision).

What are the risk factors for Retinal Vein Occlusion?

Risk factors for Retinal Vein Occlusion include: hypertension, diabetes mellitus, cardiovascular disease, primary open angle glaucoma.

What are the types of Retinal Vein Occlusion?

There are two types of Retinal Vein Occlusion:

• Central Retinal Vein Occlusion (CRVO)
• Branch Retinal Vein Occlusion (BRVO)

How is Retinal Vein Occlusion diagnosed?

Retinal Vein Occlusion is diagnosed clinically with a dilated eye examination. Additional imaging such as fluorescein angiography and ocular coherence tomography (OCT) may be needed to confirm the diagnosis and monitor the progression of the disease.

Treatment:

Treatment of Retinal Vein Occlusion includes:
Ocular treatment:

• Observation if only a small vein is involved and does not affect the macula (central part of the vision).
• Intravitreal injections of either anti-vascular endothelial growth factor (anti-VEGF) agents or steroid injection to treat the macular edema.
• Laser photocoagulation may be administered to the peripheral ischemic retina.

Systemic treatment:

• Management of systemic factors (close control of blood pressure and blood sugar levels).

Prognosis:

Retinal Vein Occlusions tend to have a relatively good prognosis if diagnosed and treated early. Delayed treatment may result in permanent retinal ischemia, neovascular glaucoma and tractional retinal detachment.