Effects Of Ranibizumab Before Vitrectomy In Patients With Proliferative Diabetic Retinopathy

Objective:Investigate expression level of VEGF and PEDF in aqueous humor and serum, and explore effect of preoperative treatment of ranibizumab on vitrectomy in proliferative diabetic retinopathy (proliferative diabetic retinopathy, PDR) patients.Methods:A total of 70 PDR patients underwent 23G vitrectomy from March 2014 to January 2015 were randomly divided into two groups. Group A (n= 36 cases,38 eyes): No treatment with ranibizumab preloperatively; Group B (34 cases,36 eyes): intravitreal injection of ranibizumab preoperatively. In addition, simple age-related cataract as a control group and set as Group C (20 cases,20 eyes). Expression of VEGF and PEDF in serum and aqueous humor were measured by ELISA in group B and group C preoperatively and postoperatively. All patients were followed up 12-16 weeks.Results:Operation time of group B was shorter than group A (67.78+20.47 vs 101.84 ±31.52, min, P= 0.000); Amount of bleeding in group A is more than group B (34.21% vs 8.33%, P= 0.007); There was no significant difference between group A and group B in occurrence of intraoperative iatrogenic retinal break. Visual acuity was significantly better in group B compare with group A during 1-6 weeks postoperatively (P<0.001), however, no difference was shown between group A and group B during 7-12 weeks. VEGF expression level in aqueous humor was significantly higher before treatment of ranibizumab in group B compare with post-treatment of ranibizumab and control group (P= 0.000). Serum VEGF was significantly higher in group B compare with control group, while no difference was shown between before and after treatment with ranibizumab; expression level of PEDF in aqueous humor was significantly lower in group B compare with post-treatment of ranibizumab and control group (P= 0.000). Serum PEDF was significantly higher in group B compare with control group, while no difference was shown between before and after treatment with ranibizumab.Conclusions:1. Preoperative injection of Ranibizumab in patients with PDR shortens operation time, reduces the incidence of bleeding and other complications, and reduces retinal neovascularization, formation of fibrous proliferation and retinal edema in PDR patients, and delays development of PDR.2. Preoperative injection of ranibizumab decreases VEGF expression and increases PEDF expression in the eye, however, has no effect on expression of VEGF and PEDF in blood. This suggests local effect of Ranibizumab is significant and safe.