Diabetic Macular Edema: From Old Concepts to New Therapeutic Avenues

Diabetic macular edema (DME) is an important cause of blindness in the working population and is currently challenging to treat. Current interventions include focal laser or intravitreal injections. This article outlines a new treatment protocol based on the concept that peripheral ischemia is the introduction to angiogenesis, that will ultimately gather its momentum at the fovea. Performing extreme peripheral light laser panretinal photocoagulation (PRP) back to the equator reduces excessive expression of the vascular endothelial growth factor (VEGF) in the eye. Subsequently, this decreases VEGF-induced DME and provides long-term protection for the development of neovascularization. Initial exacerbation of DME often accompanies PRP, Therefore; first injections of anti-VEGF agents (with or without dexamethasone implant) can forestall worsening of DME preventing loss of vision. However, on the other hand, applying peripheral PRP and intraocular injections can induce posterior vitreous detachment (PVD). This could help release vitreomacular adhesions (VMA) and vitreomacular traction (VMT), decreasing DME severity and improving response to intravitreal injections. The current approach works by laser ablation of the peripheral retina that should stop the drive for VEGF release; moreover, laser ablation should produce secondary, accidental and beneficial PVD. This approach precludes focal laser therapy and paves the path for prolonged anti-VEGF therapy.