BackgroundIt is not clear whether macular laser combined with anti-vascular endothelial growth factor (VEGF) can reduce the number of anti-VEGF injections in the treatment of macular edema (ME) secondary to branch retinal vein occlusion (BRVO). Our study aimed to investigate the effects of intravitreal ranibizumab with or without macular laser for ME secondary to BRVO and its associated number of anti-VEGF injections.MethodsThis is a prospective, randomized, double-blind, monocentric trial.80 patients were enrolled and 64 patients fulfilled the study requirements. All patients received a minimum of 3 initial monthly ranibizumab injections, pro re nata (PRN) dosing thereafter VA and CRT stabilization criteria-driven PRN treatment. Laser was given 7 days after third ranibizumab injection in ranibizumab with laser group. The follow-up time of this study was 1 year. Best corrected visual acuity (BCVA) improvement, central retinal thickness (CRT) reduction and number of injections of patients were compared between two groups. T-test, non-parametric Wilcoxon test and chis-square tests were adopted for between-group comparisons.ResultsThirty patients received intravitreal ranibizumab 0.5 mg alone and 34 patients received intravitreal ranibizumab 0.5 mg with macular laser. At 52 week, BCVA increased significantly and CRT decreased significantly in both groups (P < 0.001). However, there was no significant difference in BCVA improvement with baseline BCVA adjusted (p = 0.5226), and in the CRT reduction (P = 0.4552) between two groups after 52 weeks. There was also no significant difference in the number of injections between the two groups. (P = 0.0756). There was also no significant difference between ischemic and non-ischemic groups in BCVA improvement, CRT reduction and number of injections (P > 0.05).ConclusionsOur study suggests that ranibizumab combined with macular laser is effective in the treatment of ME secondary to BRVO after 1 year of treatment with 3 + PRN regimen. However, combination of macular grid photocoagulation showed no beneficial anatomical or functional effect during follow-up period, nor did it reduce the number of ranibizumab injections, either in ischemic group or non-ischemic group. We suggest that there is no need to combine macular grid photocoagulation in the treatment of ME secondary to BRVO in the future.Trial registrationClinical Trials NCT03054766. https://register.clinicaltrials.gov.Prospectively registered.