Efficacy and safety of four-weeks versus twelve-weeks loading doses spacing of intravitreal Aflibercept for treatment of macular edema associated with Central Retinal Vein Occlusion

The proposed research aims to answer the question about efficacy and safety of 4 weeks versus 12 weeks spacing of loading doses of intravitreal aflibercept for treatment of macular edema secondary to central retinal vein occlusion. The 4 weeks spacing is the conventional injection protocol used by many centres of injection worldwide. The 12 weeks spacing is used only in Egyptian General Authority for Health Insurance hospitals based on evidence reported in the literature that post aflibercept injection macular edema-free interval was as long as eight weeks or more. A randomized clinical trial will be conducted to answer the question and tell us which strategy results in better vision with lower number of injections after the one year follow up interval of those patients. aims of study: At the end of the study, in which group the patients received a smaller number of injections with better visual acuity. At the end of study, in which group, the patients received a smaller number of injections with best central macular thickness reduction documented by Heidelberg Spectralis Optical coherence tomography (OCT).