What Is Retinal Vein Occlusion?
Retinal veins carry blood away from the eye after oxygen and nutrients have been delivered through the retinal arteries. When a retinal vein is blocked (occluded), pressure builds up in the affected vein, causing blood and fluid to leak into the surrounding retina. This leakage can cause retinal swelling and damage. If the macula, the part of the retina responsible for sharp central vision, is affected, vision may become blurred or impaired.
A scan of the macula showing severe swelling due to the vein occlusion.
Severe retinal vein occlusion with macular swelling.Causes and Risk Factors
Other conditions, including sleep apnoea and certain blood or inflammatory disorders, may also increase the risk in some people, particularly younger patients.
Symptoms
Symptoms of retinal vein occlusion may include:
- Blurred or reduced vision in one eye
- Distorted central vision
Some people may have few or no symptoms, especially in milder cases.
Retinal vein occlusion can also lead to complications such as macular edema, abnormal blood vessel growth, bleeding inside the eye and neovascular glaucoma.
Types of Retinal Vein Occlusions
Treatment Options
Intravitreal Injection Therapy: If the occlusion has led to swelling of the macula (macular edema), intravitreal injection therapy may be recommended to reduce the swelling and help protect central vision. This involves the injection of medications into the eye using a very tiny needle.
Anti-VEGF medications such as Lucentis, Eylea and Vabysmo, as well as sustained-release steroids such as Ozurdex, may be used to treat retinal vein occlusion and its complications. Intravitreal injections are performed as outpatient or day surgery procedures.
Laser Therapy: In some cases, laser therapy may be used to treat complications of retinal vein occlusion, such as abnormal blood vessel growth. In selected cases of BRVO, laser treatment may also be considered for persistent macular oedema. The type of laser treatment depends on the location and complications of the occlusion.
Drugs are delivered directly into the eye for maximum effect.FAQs about Retinal Vein Occlusions
Having a CRVO or BRVO may be associated with underlying vascular risk factors. In some cases, another vein occlusion may occur in the same eye or the other eye. Poorly controlled high blood pressure, diabetes and high cholesterol can increase the risk of retinal vascular problems, so identifying and managing these risk factors is an important part of managing retinal vein occlusion.
A medical assessment may be recommended to check for underlying conditions, particularly in younger patients or those with recurrent or bilateral retinal vein occlusions.
Yes. Retinal vein occlusion can cause permanent vision loss, particularly when there is significant macular damage, retinal ischemia or complications such as neovascularisation. However, the degree of vision loss varies, and some patients may experience improvement with appropriate treatment and monitoring.
A retinal vein occlusion is diagnosed through a detailed eye examination, including a dilated retinal examination. OCT (optical coherence tomography) may be used to check for macular oedema and retinal changes, while fluorescein angiography may be performed in selected cases to assess retinal blood flow and areas of reduced circulation.