Vitrectomy For Diabetic Macular Edema

After 10 years with diabetes, diabetic macular edema (DME) is present in 25% of patients with type 1 diabetes and 14% of patients with type 2 diabetes. DME is thought to be caused by microvascular leakage and capillary nonperfusion, which have systemic, biochemical, and mechanical underpinnings. DME can be classified as either focal or diffuse. Although the Early Treatment of Diabetic Retinopathy Study (ETDRS) showed a clear benefit of laser treatment for DME, many patients with diffuse DME do not achieve benefit from laser therapy. In these patients a pars plana vitrectomy may be necessary, particularly in cases involving vitreomacular traction. Vitrectomy has been shown to improve vision by 2 lines or more in 57% of patients and to decrease foveal thickness.

Based on available evidence, the following treatment strategy has been suggested. Patients who show focal DME upon angiography can be treated with laser therapy. For patients with diffuse DME, an optical coherence tomography (OCT) test is needed to determine if vitreomacular traction is present. If no traction is present, laser therapy or laser therapy combined with steroid therapy can be used. If that approach is not successful, a vitrectomy with internal limiting membrane is a therapeutic option. Patients who have vitreomacular traction will likely require a vitrectomy.