Proliferative diabetic retinopathy (PDR) is one of the serious ocular complications of patients with diabetes mellitus and also the leading cause of blindness.Pars plana vitrectomy (PPV) is an effective treatment for severe vitreous hemorrhage and PDR.The intraocular concentration of vascular endothelial growth factor (VEGF) of patients with PDR usually increase abnormally, which promote growth of neovessels and make it early to leak and bleed.Numerous neovessels in vitreous cavity and retinal surface can lead to intraoperative bleeding and may affect the definition and precision of operation and prolong surgical time.If we conduct gas/fluid exchange regardless of severe active bleeding, proliferate membrane may reoccur at a high rate postoperatively due to the residual platelet and impair the success rate of surgery seriously.In addition, with the high activity of neovessels, anterior chamber, vitreous and retinal hemorrhage may appear as well as other postoperative complications like postoperative high intraocular pressure caused by inflammation or hemorrhage and traction retinal detachment because of reoccurrence of fibro membrane, which directly affect the postoperative visual function recovery and long-term prognosis.As wide clinical application of anti-VEGF agents in recent years, studies found that preoperative intravitreal injection of anti-VEGF drugs assisted PPV can limit the activity of neovessels and significantly reduce the incidence of intraoperative and postoperative bleeding, facilitate operation, shorten surgical time and improve the success rate of surgery.In this paper, the mechanism, effectiveness, clinical utility and safety of anti-VEGF therapy assisted vitrectomy for the treatment of PDR are reviewed.

Proliferative diabetic retinopathy/therapy; Vascular endothelial growth factor; Pars plana vitrectomy