Abstract:AIM: To investigate the efficacy and safety of intravitreal injection of Conbercept combined with 25G minimally invasive pars plana vitrectomy(PPV)at the end of surgery for early proliferative diabetic retinopathy(PDR)with vitreous hemorrhage.METHODS: A total of 60 patients(60 eyes)with PDR complicated with vitreous hemorrhage requiring PPV at the Affiliated Eye Hospital of Nanjing Medical University were retrospectively analyzed. Based on the injection timing of Conbercept, the patients were divided into 3 groups: 20 patients(20 eyes)injected at the end of the surgery(group A), 20 patients(20 eyes)injected preoperatively(group B), and 20 patients(20 eyes)without injection(group C). The differences in pre- and post-operative visual acuity, intraocular pressure, intraoperative conditions, prognosis, and complications were analyzed among the 3 groups.RESULTS: There were no significant differences in the preoperative conditions and operation time among the patients. There was no iatrogenic retinal hole or silicone oil tamponade during the operation in the 3 groups, and no recurrent retinal detachment occurred after the operations. Best corrected visual acuity(BCVA)at 1, 3 and 6mo of all groups were improved compared with those before the surgery(P<0.05), and the injection groups(group A and group B)had a significantly better postoperative improvement than the non-injection group(group C), and there were significant differences(P<0.05). The incidence of postoperative late vitreous hemorrhage(1mo after operation)in group A was significantly lower than those in groups B and C(P<0.05). The central retinal thickness of the operated eyes in the injection groups(groups A and B)was significantly lower than that in the non-injection group(group C)at 1, 3 and 6mo after operation(P<0.05).CONCLUSION: Conbercept injection at the end of the surgery and preoperative injection are both safe and effective for early PDR and can significantly improve postoperative visual acuity. However, Conbercept injection at the end of surgery can reduce the risk of late vitreous hemorrhage recurrence, leading to better PPV outcomes and improving patients' retinal and visual function and quality of life.