The endothelial growth factor (VEGF), has been implied in the genesis of diverse Neovascular disease. In the industrialized and developing countries, the main cause of blindness is the diabetic retinopathy. Bevacizumab (Avastin, genentech, Inc., San Francisco, California, the USA) is a drug.In the last years its use "off-label", in ophthalmology field, has become popular. This is due to its proven safeness and effectiveness for the treatment of diverse ocular diseases. A lot has been speculated about the systemic absorption of Bevacizumab. It is for that reason that the objective of this study is the systematic and random revision of the fellows eyes, of the patients programmed for the intravitreal administration of Bevacizumab, with bilateral macular edema. In such a way that the therapeutic value in the fellow eye of bevacizumab can be determined