Comparison of Safety and Efficacy of Grid Laser Versus Combination of Sequential Intravitreal Triamcinolone Acetonide and Grid Laser in Treatment of Diabetic Macular Oedema - Randomized Open Label Study, Bangalore, Karnataka

BACKGROUND The reported prevalence of diabetic retinopathy in diabetics is around 40 %. Diabetic macular oedema (DME) is defined as macular thickening resulting from diabetic retinopathy, due to leakage from micro aneurysms, or from a diffuse leakage of hyper permeable capillaries. Intravitreal injection of triamcinolone acetonide (IVTA) has gained considerable interest and clinical use because it often has beneficial effect on retinal thickening in DME. The synergistic action of IVTA and laser photocoagulation might increase and prolong the beneficial effects of IVTA in reducing ME. Hence the need for a study to compare efficacies of grid laser, and combination of sequential IVTA and grid laser in treating patients with DME. We wanted to evaluate functional and morphological outcome of grid laser versus combination of sequential intravitreal triamcinolone acetonide and grid laser in treatment of diabetic macular oedema. METHODS The study included 62 eyes with DME. There were 31 eyes which received grid laser photocoagulation (group 1) and 31 eyes which received grid laser photocoagulation following IVTA (group 2) and visual acuity, CMT on OCT was compared at baseline and after day 1, 1st week, 4th week and 12th week. Outcome and comparative efficacies were evaluated. RESULTS Our study shows reduced macular thickness and improved visual acuity in group 2 compared to group 1 in all follow ups. On intragroup analysis, we found a significant reduction in CMT in both groups at 1 week, 4 weeks and 12 weeks as compared to baseline. In our study we also compared CMT between group 1 and group 2 which did not show significant difference at baseline. But, difference in CMT from baseline at each follow up which is at 1 week, 4 weeks and 12 weeks between two groups showed more reduction in CMT in group 2 compared to group 1. CONCLUSIONS There was a significant reduction in CMT in all the follow ups of both groups, but group 2 had more reduction in CMT compared to group 1. The synergistic action of IVTA and laser photocoagulation might increase and prolong the beneficial effect of IVTA in reducing ME. This study found evidence of synergistic effects of IVTA and laser photocoagulation in DME in terms of improving visual acuity and in reducing CMT compared to grid laser alone and should be tried as a modality of treatment in DME. KEYWORDS DME, IVTA, CMT, Macular grid laser, OCT