Comparison of Therapeutic Efficacy of Intravitreal Bevacizumab plus Macular Laser versus Intravitreal Triamcinolone Acetonide plus Macular Laser in Primary Treatment of Diabetic Macular Edema

To compare the efficacy of intravitreal bevacizumab and macular laser vis-a-vis intravitreal triamcinolone acetonide and macular laser in primary treatment for diabetic macular edema. Randomised, prospective, comparative two-arm, non-interventional study with five time points. 60 eyes of 30 patients with bilateral DME and no previous ocular intervention participated in the study and were randomised into two groups. Both eyes of Group A patients received an intravitreal injection of 1.25mg of Bevacizumab and Group B patients received 4mg of Triamcinolone acetonide. One week after injection, all patients underwent macular photocoagulation. The clinical course of best corrected visual acuity (BCVA) in decimal fraction system and average central retinal thickness (CRT) using optical coherence tomography was monitored for up to 12 weeks after the injection. Before injection, mean of CRT and BCVA were 411.37±165.71μ and 0.252±0.154 in Bevacizumab group (A) and 356.50 ± 152.26μ and 0.378 ±0.248 in Triamcinolone group (B). Two weeks after injection and one week after macular photocoagulation (MPC), both groups showed significant regression of macular edema and improvement in vision. Bevacizumab group showed better results at 2weeks.The difference in CRT and BCVA at 2 weeks from baseline were 84.40 ± 22.68μ (p= .008) & 0.111 ± 0.015 (p< .001) in group A and 52.30± 15.63μ (p= .023) & 0.089± 0.033 (p= .113) in group B. The efficacy of Triamcinolone improved 4 th week onwards, became comparable to Bevacizumab group at 8 th week. At 12 weeks, the Triamcinolone group achieved slightly better results than Bevacizumab group, which started showing recurrence of macular edema. The differences in CRT at baseline and at 12 weeks in group A and group B respectively are 102.47 ± 23.50 μ(p= .001) and 108 ± 21.60 μ(p< .001).The differences in between baseline and BCVA at 12weeks in group A and group B respectively are 0.210± 0.026 and 0.214±0.04. Within the study period and with the generally used concentration, intravitreal bevacizumab, as treatment modality brings earlier reduction in DME, but at 4 and 8 weeks, the efficacy in terms of pvalue in between two groups is similar. At 12 weeks bevacizumab group starts showing the beginning of waning effect of drug, although still comparable to Triamcinolone group. No increase in IOP was seen in bevacizumab group while one eye developed raised IOP in Triamcinolone group.