This is an unfortunate condition effecting the main vessels in the back of the eye. It usually occurs in elderly patients and leads to a permanent reduction in vision in that eye.
  The retina is the delicate light sensitive layer in the back of the eye.There is only one central VEIN which drains all the blood from the retina.At the point where this main vein leaves the eye, it shares a common wall with the central retinal ARTERY. The vein may become occluded in a variety of settings. Because of its close association with the artery, any disease effecting the arterial wall may cause obstruction in the vein. This is why arteriosclerosis (hardening of the arteries) is the most common cause of this disorder.
   Other systemic disorders which may contribute the C.V.O.'s are diabetes, high blood pressure, and certain rare blood disorders. Most often patients are in good health prior to the onset of the occlusion.
  There are several eye related problems which are related to C.V.O.'S. This list includes glaucoma, optic nerve abnormalities, and localized arterial disease in the retina itself.There is usually a profound, painless loss of vision with closure of the retinal vein. In most, the vision loss is sudden and worsens over a few days. Only with time does the vision improve.
   There is no known effective TREATMENT for this problem. The duty of the eye physician is to establish a cause, if one can be found and monitor the eye for any complications. The two most common complications are:
    1. New blood vessel growth on the surface of the retina. These new vessels, even though well intentioned, are always abnormal and will lead to hemorrhages inside the eye if left untreated.
   2. New vessels may form on the colored part of the eye (iris). This condition is called RUBEOSIS and may lead to a painful form of glaucoma and repeated hemorrhages in the eye.The good news is that both of these complications are treatable with medicines, LASERS and other methods.
   THE KEY TO TREATING THE COMPLICATIONS OF C.V.O.'S IS EARLY DETECTION. That is why after a C.V.O., patients need to be frequently examined for several months. The final visual outcome is dependent upon the extent of cell damage done at the time of the original occlusion and upon the results of any treatments done for the previously mentioned potential complications.
  A disorder similar to C.V.O. may occur in younger age groups; here the outlook is much better, and good vision is usually preserved.

© nholland 2002