Retinal vein occlusion is a common cause of sight loss. The retina is the light sensitive lining of the inside of the eye. If there is a blockage of the circulation it can damage the retina and cause temporary or permanent loss of vision.
Retinal vein occlusion usually only affects one eye at at a time, causing a painless loss of vision in part of or all of the vision. The blockage causes bleeding into the retina and swelling of the retina. There are two types of retinal vein occlusion.
- Central retinal vein occlusion. In this case, the blockage occurs where the main retinal vein enters the eye. The whole of the retina is therefore affected and can be potentially damaged. Patients tend to experience a big drop in all of their field of vision. This type of occlusion is harder to treat and is less likely to settle by itself.
- Branch retinal vein occlusion. In this type of occlusion, the blockage occurs in one of the branches of the main retinal vein. Only part of the retina is therefore affected. Patients may experience varying degrees of vision loss and may be aware that part of their field of vision seems okay whilst in the rest the vision is worse. This type of occlusion may sometimes settle itself without active treatment.
Depending on the type of retinal vein occlusion, different treatments may be required.
What causes a retinal vein occlusion?
In some cases a retinal vein occlusion may be caused by high pressure within the eye. This would be checked when you are examined. More commonly the occlusion is caused by other medical problems which increase the tendency for blood to clot. These include high blood pressure, high blood cholesterol, diabetes and smoking. There are also rare blood conditions which might have been the cause. As part of your assessment testing for these conditions may be advised or if you are already affected by any of these conditions their control may need assessing.
What are the treatments for retinal vein occlusion?
You will initially be examined to confirm the type of retinal vein occlusion you have and it's severity. As well as an eye examination other tests may be required such as OCT scanning and special photography to assess the circulation of your eye. You may be offered one of the following or a combination of these treatments.
- Observation. In some cases if the problem is showing signs of settling it may be better to continue observation. There is however increasing evidence that earlier treatment is beneficial so this will need to be considered depending on your case. In severe cases active treatment may not be appropriate and treatment only advised if further complications are seen from the vein occlusion such as high pressure in the eye or abnormal blood vessel formation.
- Laser. This was historically the treatment of choice in some times of branch retinal vein occlusion and central retinal vein occlusion to treat new blood vessel formation. It may still be appropriate in your case but is being superseded by the newer eye injection treatments.
- Anti-VEGF injections. When an eye is affected by retinal vein occlusion there are increased levels in the eye of a chemical called vascular endothelial growth factor (VEGF). This chemical is produced in greater quantities when the circulation is reduced and contributes to the process of leakage and bleeding into the retina. New injectable drugs which counteract this rise in VEGF are called Lucentis, Avastin and Eylea. Many studies have shown the benefits of a series of injection treatment for patients with both branch and central retinal vein occlusion. This treatment approach appears to be superior to laser treatment and there is more of a chance of getting significant improvement in vision.
- Steroid injections. An alternative to anti-VEGF injections is steroid injections. This may be in a standard liquid form or a slow release implant such as Ozurdex. Steroids have a slightly higher rate of side effects compared to anti-VEGF injections. However, they have the potential advantage of a longer lasting effect and not as many injections are required.
The appropriate choice of treatment for you would be discussed after a detailed discussion of the nature of the problem in your case. The pros / cons and risks of each treatment may also differ depending on your specific eye and other problems you may already have. Whereas in the past treatment options and results from them were limited, there is more of a hope now of treatment which can have a positive effect and offer improvement.
If you have been affected by any of the symptoms mentioned above, please don't hesitate to give us a call.
We have a team of experts on stand-by who are ready to take your call at our Manchester (0161 907 2685) Clinic or our Blackpool (01253 308 031) Clinic.