Vein occlusion 22/03/2013

What is retinal vein occlusion? 

Retinal vein occlusion is the second most common cause of vascular disorders of the retina after diabetic retinopathy, and a frequent cause of blindness.

It is defined as the dilation of the retina's veins, with haemorrhaging, intraretinal oedema, retinal ischaemia and macular oedema.

Main causes

The cause is not entirely known but, essentially, the vein walls undergo external compression, at the level of the lamina cribrosa in the optic nerve in the cases of central retinal vein occlusion and at the level of arteriovenous crossings in those cases of branch retinal vein occlusion.

The risk factors for retinal vein occlusion are as follows:

— Open angle glaucoma.

— Cardiovascular disease.

— Hypertension.

— Hyperlipidaemia and hypercholesterolaemia.

— Diabetes mellitus.

— Thrombophilia.

Symptoms 

There is a loss of vision or blurring, sudden and painless, which may initially be minimal but usually gets worse over the next few hours or days. In some cases, there is almost immediate acute loss of vision.

If these symptoms occur, it is very important to request an appointment with a retina specialist as soon as possible. Retinal vein occlusion often causes permanent damage to the retina and loss of vision. It is important to deal with and avoid complications appropriately, as in the case of macular oedema, neovascular glaucoma and proliferative retinopathy.

How is it treated? 

Treatment focuses on two objectives: 1) identifying risk factors that can be modified and their medical treatment, and 2) identifying and treating any complications that jeopardise vision.

A thorough ophthalmological examination is crucial, which also includes the following tests: a retina scan, autofluorescence, optical coherence tomography and fluorescein angiography, also wide field.

Today several drugs are available that have radically changed the visual prognosis for such patients. In addition to treating macular oedema via different strategies or their combination (injections of angiogenesis inhibitors, sustained release corticosteroids, micropulse photocoagulation), the serious consequences must also be prevented of more severe ischaemia via extensive photocoagulation of the affected retinal areas. In some extreme cases surgery will be necessary, both for retinal complications and also those of neovascular glaucoma. Today, thanks to advances in therapy, the incidence of such extreme cases is increasingly rare.

Research, a fundamental ingredient in the future of vision 

In its mission to offer its patients the best and most innovative treatments, the Institut de la Màcula is carrying out clinical trials for the treatment both of central and branch occlusions in order to improve the quality of their sight, in close collaboration with the Barcelona Macula Foundation.

We have state of the art equipment to detect microscopic changes that make a big difference when studying the progression of illnesses.