Macular Grid Photocoagulation After Intravitreal Triamcinolone Acetonide for Diffuse Diabetic Macular Edema

OBJECTIVE: To evaluate the clinical outcomes of macular laser photocoagulation after the intravitreal injection of 4 mg of triamcinolone acetonide (IVTA) for diffuse diabetic macular edema (DME). METHODS: Eighty-six eyes of 74 patients with diffuse DME were randomized into 2 groups. The laser group eyes (n = 48) were subjected to a macular grid laser photocoagulation 3 weeks after IVTA. The control group eyes (n = 38) underwent only IVTA. Both groups were compared with regard to the changes in visual acuity and central macular thickness at 3 weeks, 3 months, and 6 months after IVTA. RESULTS: The mean central macular thickness before, 3 weeks after, and 3 and 6 months after IVTA were 538, 250, 295, and 301 mum in the laser group vs 510, 227, 302, and 437 mum in the control group, respectively. The logMAR visual acuities were not significantly different between the 2 groups at baseline and at 3 weeks after IVTA but were significantly better in the laser group at 3 (P = .02) and 6 months (P<.001) after IVTA. CONCLUSIONS: Macular laser coagulation effectively maintains improved visual acuity after IVTA for diffuse DME and is believed to reduce recurrent DME after IVTA.