Surgical Management of Diabetic Macular Edema.

Abstract

Diabetic macular edema (DME) is typically caused by leakage from abnormal retinal blood vessels. Mechanical causes at the vitreoretinal interface are increasingly implicated in select patients. Surgical interventions, including vitrectomy, epiretinal membrane (ERM) peel, and internal limiting membrane (ILM) peel, have been proposed in these patients to relieve traction, clear cytokines, and improve oxygenation. This chapter reviews the efficacy of these interventions, which varies by the type of vitreoretinal interface abnormality. Vitrectomy is beneficial in most DME cases where a taut posterior hyaloid or vitreomacular traction is present. It can also be beneficial in select cases where the posterior hyaloid is attached, even if there is no observable traction. When separation of the posterior hyaloid has occurred, vitrectomy can still be beneficial if an ERM is present. Unfortunately, favorable anatomic results, including improved thickness on optical coherence topography scans, are more common than improved visual results. This may reflect that surgical intervention is often performed for refractory DME cases with long-standing edema, with limited potential for substantial improvement. However, surgical intervention may be beneficial for select cases of DME, especially when surgical intervention is undertaken before photoreceptor damage has occurred.