Retinal vein occlusion is a vascular condition in which the vein which exits the retina becomes blocked, meaning that blood cannot safely drain from the retina. As a result, pressure builds up in the eye, and the patient may develop a hemorrhage. Most notably, the condition leads to a loss of vision in the affected eye which can be partial or full, depending on the type of occlusion and whether or not it is treated quickly. This condition is treated as an opthalmologic emergency, requiring prompt medical attention for the best prognosis.
The retina is served by an artery and a vein. People can develop retinal artery occlusion, in which the supply of blood to the retina is blocked, or retinal vein occlusion, in which the outflow is obstructed. In both cases, if the occlusion is treated within two hours, it can prevent damage to the eye, and the prognosis may continue to be good for patients who receive an intervention within a day. The condition is usually painless as well, although patients usually feel disoriented and nervous about the associated vision loss.
The key symptom of retinal vein occlusion is loss of vision, which is often partial at first. If someone experiences severely blurred vision, visual obstruction, or sudden blindness in one eye, it may be a sign of retinal vein occlusion, and it should be treated immediately. A doctor can diagnose the problem by looking into the eye, and determine the best course of treatment. Treatments are partially determined by whether the occlusion is ischemic, meaning that oxygen is cut off, or nonischemic, in which case the supply of oxygen to the retina is not interrupted.
Sometimes, clearing the occlusion and aspirating some fluid from the eye to relieve pressure will resolve the problem. In the case of a branch retinal vein occlusion (BRVO), prompt intervention can sometimes save the patient's vision. A central retinal vein occlusion (CRVO) in which the central vein is blocked can be a more serious problem.
People with diabetes are more prone to retinal vein occlusion than others, as are older individuals and people who suffer from syphilis. The condition can lead to glaucoma and other problems with the eye if it is not treated. In the event that a retinal vein occlusion has cost someone his or her vision, a doctor may still recommend treatment to address complications of the occlusion, to keep the patient as comfortable as possible.