Two year result of intravitreal bevacizumab for diabetic macular edema using treat and extend protocol

Abstract

To determine the efficacy of the treat and extend (TAE) protocol with intravitreal bevacizumab (IVB) for managing diabetic macular edema (DME).Retrospective, single-center study.For this retrospective study, 42 eyes of 42 patients were initially treated with 3 consecutive monthly IVB injections (loading phase), after which they were selected for different additional therapies. For the TAE protocol, the baseline treatment interval was selected to be 8 weeks and was sequentially lengthened by 2 weeks if the central macular thickness (CMT) was <300 μm at 2 consecutive examinations.Among the 42 eyes, 8 eyes (19.0%) received the TAE treatment for 2 years. The BCVA was improved significantly from 0.37 ± 0.04 before treatment to 0.19 ± 0.04 logMAR units at 2 years after the TAE determined IVB injections (P < .05). The ratio of eyes with a gain of the BCVA by more than 2 lines was 37.5%. The CMT was significantly reduced from 515.4 ± 75.5 to 303.6 ± 45.0 μm after 2 years (P < .01). The mean number of TAE injection was 8.8 and the mean injection interval was 11.0 weeks.After the loading phase, 19.0% of patients can be treated with the TAE protocol. Although significant visual improvements were obtained after the TAE protocol, it does not apply to every DME case.

Figure 1

Flow chart showing progression of subjects through the study. IVB = intravitreal bevacizumab, IVTA = intravitreal triamcinolone acetonide, PRN = pro-re-nata, TAE = treat and extend.

Figure 2

Representative case treated with the TAE protocol. Before treatment, his log MAR BCVA was 0.4 and the CMT was 632 μm (A). After the loading phase, cystic edema resolved and the log MAR BCVA was 0.4 and the CMT was 491 μm (B). Then, 4 IVB injections with the TAE protocol were performed, the log MAR BCVA was 0.22, and the CMT was reduced to 266 μm (C). After 10 injections of IVB with the TAE protocol, the log MAR BCVA was improved to be 0.15 and CMT also improved to 232 μm with a TAE interval of 12 weeks. BCVA = best corrected visual acuity, CMT = central macular thickness, IVB = intravitreal bevacizumab, TAE = treat and extend protocol.