Retinal Laser Photocoagulation

Laser energy destroys ischemic retinal tissue to reduce VEGF secretion, halt pathological neovascularization, and prevent sight-threatening complications — a cornerstone treatment for diabetic retinopathy and retinal vein occlusion.

Retinal laser photocoagulation has been a mainstay of retinal vascular disease treatment for over 60 years and remains a standard of care for diabetic retinopathy (DR) and retinal vein occlusion (RVO). Laser energy absorbed by the retinal pigment epithelium creates focal thermal coagulation, destroying ischemic photoreceptors in areas of poor perfusion. By reducing the metabolic oxygen demand of these zones, total retinal VEGF production decreases, inhibiting pathological neovascularization and preventing serious complications such as vitreous hemorrhage and tractional retinal detachment. There are three main modalities: Pan-retinal photocoagulation (PRP) — used for proliferative DR (PDR) or extensive ischemic RVO, delivering 1,500-2,000 laser spots across the peripheral retina (sparing the macula and disc), typically over 2-3 sessions; Focal photocoagulation — direct treatment of leaking microaneurysms in non-center-involving diabetic macular edema; Grid photocoagulation — a grid pattern of burns over edematous retina (largely superseded by anti-VEGF injection for macular edema). While anti-VEGF injections have replaced laser as the primary treatment for macular edema, PRP remains irreplaceable for managing new vessels in PDR and preventing catastrophic complications. Its lower cost and avoidance of repeated injections make it a critical option in resource-limited settings and a complementary tool in comprehensive retinal care.