Retinal Vein Occlusions

What is a retinal vein occlusion?

The light-sensitive tissue at the back of your eye is called the retina. Retinal arteries provide the retina with nutrients, whilst the retinal veins take the blood away from the retina. The smaller 'branch' retinal veins all converge at the optic nerve, to form one large 'central' retinal vein. 

Uncommonly, these veins can become blocked (or occluded), resulting in a reduction in blood flow, retinal haemorrhage and oedema of the retina. In the worst cases, abnormal blood vessels can grow, causing significant scarring and severe glaucoma.

A Central Retinal Vein Occlusion (CRVO) occurs when the central vein is blocked, whereas a Branch Retinal Vein Occlusion (BRVO) occurs when a smaller branch vein is occluded.

This is a photograph of a BRVO:

What are the causes of retinal vein occlusions?

Systemic medical conditions, such as high blood pressure and hardening of the arteries, can increase your risk of a retinal vein occlusion. As such, retinal vein occlusions tend to be more common as you get older.

Other risk factors include:

What tests may I need if I have a retinal vein occlusion?

Whilst diagnosing a retinal vein occlusion is normally very easy on clinical examination, extra tests are required to determine its severity and to determine the most appropriate treatment. 

Most commonly, an OCT is performed to assess macular oedema (swelling). 

Fluorescein angiography is also an important test in retinal vein occlusions. This test is essential for determining how well (or poorly) the blood is flowing through the occlusion. This information is necessary for determining the best treatment, and the likelihood of further deterioration.

What is the treatment of retinal vein occlusions?

The treatment depends on how the vein occlusion has damaged the retina. If there is no threat to your vision, then no treatment may be required.

However, if your vision has deteriorated, or if there is significant risk that it may deteriorate in the future, then some form of treatment is likely to be required.

The 2 most commonly used treatments include intravitreal injections and retinal laser.

If there is significant macular oedema (swelling), then injections into the eye have been shown to be the most effective way of improving and stabilising vision. If there are areas of very poor blood flow, then retinal laser may be indicated. Occasionally a combination of laser and injections are required. 

Dr Johnson will discuss the most appropriate treatment in your case.

For more information about intravitreal injections, please click here.

For more information about retinal laser, please click here.

Dr Joshua Yuen

Dr Joshua is an experienced consultant ophthalmic surgeon, who specialises in retinal diseases and cataract surgery... read more

Dr Brad Johnson

Dr Johnson is an experienced consultant ophthalmic surgeon, who specialises in retinal diseases and cataract surgery... read more