To compare safety and functional outcomes of vitrectomy with or without preoperative intravitreal bevacizumab (IVB) for proliferative diabetic retinopathy (PDR).

A meta-analysis of randomized controlled trials.

PubMed, Medline, EMBASE, and Cochrane Controlled Trials Register were searched to identify potentially relevant randomized controlled trials. A total of 394 participants with 414 eyes in 8 trials were analyzed using RevMan 5.1 software. The primary measures included intraoperative bleeding, total surgical time, and early and late recurrent hemorrhage.

Vitrectomy with IVB pretreatment achieved shorter overall surgical time (mean difference = −26.89 minutes, 95% confidence interval [CI] −31.38 to −22.39, P < .00001) and smaller number of endodiathermy applications (mean difference = −3.46, 95% CI −6.43 to −0.49, P = .02) compared to vitrectomy alone. The IVB group was also associated with less intraoperative bleeding (odds ratio [OR] = 0.10; 95% CI 0.02 to 0.46; P = .003) and recurrent vitreous hemorrhage within first month (OR = 0.35; 95% CI 0.21 to 0.58; P < .0001), but the proportion of recurrent vitreous hemorrhage after the first month was comparable between both groups. There were no significant differences in other complication rates between the 2 groups, with the exception of iatrogenic retinal break, which was more likely with the vitrectomy-alone group (OR = 0.27, 95% CI 0.12 to 0.63, P = .003). Results were robust to sensitivity analyses.

Adjuvant intravitreal injection of bevacizumab prior to vitrectomy in PDR patients significantly eased the procedure, diminished intraoperative complications, and reduced early postoperative hemorrhage without increasing the risk of vision-threatening complications. Further trials should determine the optimal interval and dosage for IVB injection.