Diabetic Macular Edema: Beyond ETDRS

The Early Treatment of Diabetic Retinopathy Study (ETDRS) clearly showed that laser treatment for diabetic macular edema (DME) significantly reduced visual loss; however, there was limited visual improvement in this study. Furthermore, with laser photocoagulation, repeated treatment is often necessary, and some patients may not respond to treatment at all. Accordingly, a variety of other therapeutic options are being explored. Vitreous surgery is a useful option, particularly for patients with vitreous traction. Steroid therapy is also being used, and numerous different delivery mechanisms are available, including intravitreal injection, subtenon injection, and surgical implants. Overall, steroid therapy has been shown to improve visual acuity and reduce retinal thickness, but these results may not be effective in the longer term. Therapies that target the underlying pathophysiology of diabetic macular edema are also being explored. The anti-VEGF therapy pegatanib has been shown to improve visual acuity and reduce the need for laser photocoagulation. The protein kinase-β inhibitor ruboxistaurin reduces the progression of DME and reduces moderate visual loss, and may be particularly effective at higher levels of A1C. In conclusion, a number of promising therapies are being investigated, but more evidence is still needed before they can become part of the standard of care for patients with diabetic macular edema.