A typical sign of diabetic retinopathy is diabetic macular edema (DME), which is brought on by intraretinal fluid buildup, especially in the inner and outer plexiform layers, and is also brought on by the breakdown of the blood-retinal barrier (BRB). DME is currently one of the main causes of blindness in people of working age and its prevalence is rising globally. One of the treatments for DME is intravitreal injections of the anti-VEGF drug bevacizumab. In diffuse macular edema that is refractory to photocoagulation, intravitreal triamcinolone, or vitrectomy, the recombinant monoclonal antibody bevacizumab lowers retinal thickness and also enhances visual acuity by neutralizing the bioactivity of VEGF.