 This is an open-label, Phase I study of intravitreally administered ranibizumab in 20 subjects with macular edema associated with CRVO. Patients will be evaluated at baseline with ophthalmic examination, fluorescein angiography, optical coherence tomography, and color photography. Subjects will receive open-label intravitreal injections of 0.5 mg ranibizumab administered every 28 2 days for a total of 3 injections. Thereafter they are to be evaluated every month until month 12. If the patients have signs of increased intraretinal hemorrhage or a persistence increase in central macular edema as determined by optical coherence tomography when compared to their last visit, are eligible for re-injection at that monthly visit. 