VEGFA and retinal vein occlusion: Intravitreal injections (IVI), maximizing the intraocular concentrations while minimizing the systemic exposure, has become the standard procedure in ophthalmologic conditions such as endophthalmitis, viral retinitis, age-related macular degeneration, cystoid macular edema, diabetic retinopathy, uveitis, retinal vascular occlusions, retinal detachment to deliver several therapeutics such as anti-infective and anti-inflammatory medications, immunomodulators, anticancer agents, gas and anti-vascular endothelial growth factor (anti-VEGF) [1].