Retinal Venous Occlusive disease is the second only to diabetic retinopathy as a major cause of blindness associated with retinal vascular disease. Macular edema is a major cause of vision loss in patients presenting with central and hemi vein occlusions. Until recently the standard of care for macular edema secondary to central retinal vein occlusion was observation. Recent investigations of steroids for this condition has shown greater visual benefit but is associated with risks such as cataract formation and increased intraocular pressure. In the past laser photocoagulation has been used, but was found to offer no visual benefits over the natural history in the treatment of macular edema associated with CRVO.~Bevacizumab, an anti-VEGF agent, is a potent inhibitor of vascular permeability, with the potential to reduce retinal vascular leakage and diminish macular edema. In addition, as an anti-VEGF agent, it may also inhibit neovascularization of the iris, a frequent complication of ischemic central retinal vein occlusion. Bevacizumab use as an intravitreal agent does carry the risk of intraocular infection but probably carries very low risk of glaucoma or cataract formation, making it a potentially safer pharmacologic treatment for CRVO associated macular edema as compared to steroids.~Ozurdex (dexamethasone) Intravitreal Implant is a steroid injected into the eye to treat swelling that may occur when there is a blockage of certain blood vessels in your eyes. Ozurdex is also used to treat non-infectious uveitis affecting the posterior (rear) segment of the eye.
The purpose of this study is to determine whether Bevacizumab (Avastin) in combination with Dexamethasone (Ozurdex) will be effective in reducing if not eliminating the macular edema associated with the disease, central retinal vein occlusion (CRVO) in comparison to Bevacizumab (Avastin) alone.