The study grid laser photocoagulation after intravitreal triamcinolone and only intravitreal triamcinolone for the treatment of 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) as compared to intravitreal injection only IVTA for diffuse diabetic macular edema (DME).Method 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 ?m in the laser group vs 510,227,302,and 437 μm in the control group,respectively. The 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=0.02) and 6 months (P0.001) after IVTA.Conclusion Macular laser coagulation effectively maintains improved visual acuity after IVTA for diffuse DME and is believed to reduce recurrent DME after IVTA.