Retinal Vein Occulsion
What is Retinal Vein Occulsion?
Retinal vein occlusion is another 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:
i) 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.
ii) 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.
The most common reasons for occlusion of the blood vessel are 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 that might have been the cause.
If you suspect you have Retinal Vein Occulsion
In some cases if the problem is showing signs of settling it may be better to continue observation rather than active treatment.
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.