There is strong evidence that ranibizumab provides benefit in subjects with macular edema due to RVO; however, some subjects required continued injections for years to maintain those benefits. It is likely that such subjects have continued production of VEGF (Vascular Endothelial Growth Factor) from areas of nonperfused retina in the periphery. One strategy is to perform scatter photocoagulation to areas of nonperfusion to reduce continued production of VEGF, but it is important to know if visual benefits are maintained when this is done, because if it is not, it would be better to continue intermittent injections of ranibizumab.
