Randomized Trial of Intravitreal Bevacizumab Alone or Combined with Triamcinolone versus Macular Photocoagulation in Diabetic Macular Edema

To compare the results of intravitreal bevacizumb (IVB) injection alone or in combination with intravitreal triamcinolone acetonide (IVT) versus macular laser photocoagulation (MPC) as primary treatment of diabetic macular edema (DME). In this randomized clinical trial, 150 eyes of 129 patients with clinical DME and no previous treatment were enrolled. The eyes were randomly assigned to one of the three study arms: the IVB group received 1.25 mg IVB (50 eyes); the IVB/IVT group received 1.25mg of IVB and 2 mg of IVT (50 eyes); and the MPC group underwent focal or modified grid laser (50 eyes). Retreatment was performed at 12-week intervals whenever indicated. Visual acuity (VA) changes among the groups were statistically significant at 6 (P<0.001) and 24 (p=0.012) weeks. VA change was significant only in the IVB group at 12 weeks. VA changes±standard deviation at 36 weeks were -0.28±0.25, -0.04±0.33, and +0.01±0.27 LogMAR in the IVB, IVB/IVT, and MPC groups, respectively (P=0.053). Significant reduction in central macular thickness (CMT) was observed in all groups only up to 6 weeks; however, CMT changes were not significantly different among the groups in all visits. Overall, retreatment was required for 27 eyes up to 36 weeks (14 in the IVB group, 10 in the IVB/IVT group, and 3 in the MPC group). In the IVB group, in which greater VA improvement was observed, only one injection was required in 72% of the cases. VA improvement more than 2 Snellen lines at 36 weeks occurred in 37%, 25%, and 14.8% of patients in the IVB, IVB/IVT and MPC groups, respectively. Intravitreal bevacizumab injection in patients with DME yielded a better visual outcome at 24 weeks compared with macular photocoagulation. After 6 weeks changes in CMT and VA were not compatible. No adjunctive effect of IVT was demonstrated.