VEGFA and diabetic macular edema: The vascular endothelial growth factor (VEGF) triggers the angiogenesis modulating vascular permeability, and it is hypothesized as the key factor in the pathogenesis of DR and diabetic macular edema (Giurdanella et al., 2015; Platania et al., 2015; Bolinger and Antonetti, 2016; Bucolo et al., 2018).