We thank Dr Hu et al1 for their valuable comments. In dealing with patients with BRVO, we are inevitably faced with different coexisting pathologies, including diabetes mellitus, systemic hypertension, and ocular problems such as glaucoma. A detailed subgroup analysis of the efficacy of IVB in each group of systemic and ocular pathologies would require a substantial number of patients to enable this study to have predictive power. As for prior ocular treatments used in IVB-treated eyes, IVB was used in eyes with recurrent ME after laser photocoagulation and intravitreal triamcinolone acetonide and not as an adjunct to these treatments. A sufficient time period had elapsed after these treatments to conclude that prior treatment had not been successful. Finally, the decision to retreat was made based on the presence of macular oedema on OCT. Eyes that had persistent macular oedema were retreated, whereas those with no macular oedema skipped retreatment.

A retrospective study is valuable in that a positive outcome encourages pursuing randomized, controlled clinical trials, whereas, randomized trials are generally not pursued following negative outcomes in a retrospective study. We are encouraged that these preliminary, retrospective data on the prn usage of the anti-VEGF agent bevacizumab support the basis for conducting the prospective, randomized, controlled trial of ranibizumab, another anti-VEGF agent, for macular oedema for branch retinal vein occlusion. It is our sincere hope that this large, prospective study validates our findings and provides another tool to fight against this devastating and common cause of blindness.