Effect of Intravitreal Conbercept Injection on Complications of Pars Plana Vitrectomy in Patients with Proliferative Diabetic Retinopathy

Background: The effect of intravitreal conbercept (IVC) before pars plana vitrectomy (PPV) on surgical complications in patients with proliferative diabetic retinopathy (PDR) was observed. Methods: A total of 152 patients with PDR operated on in Jiangsu Provincial People’s Hospital from November 2019 to November 2020 were divided into two groups: 124 patients in the preoperative intravitreal conbercept injection + PPV group (IVC group) and 28 patients in the PPV only group (No-IVC group). Vitreous samples were collected in all eyes of patients who underwent vitrectomy, and the content of VEGF-A was measured by Luminex. The effect of conbercept on intraoperative and postoperative complications of PDR was assessed. Results: The content of VEGF in the vitreous of the IVC group was significantly lower than that in the No-IVC group (64.50 ± 58.40 pg/mL vs. 805.17 ± 417.60 pg/mL, p < 0.001). During postoperative follow-up, early postoperative vitreous hemorrhage (VH) occurred in 13 of 142 eyes (9.15%). Compared with the No-IVC group, PDR patients with VH and fibrovascular membrane (FVM) or high complexity in the IVC group had lower intraoperative bleeding rates (p < 0.05). The early postoperative hemorrhage rate in the IVC group was lower than in the No-IVC group (6.03% vs. 23.08%, p < 0.05). The number of intraoperative electrocoagulation and iatrogenic retinal holes in the IVC group was significantly lower than in the No-IVC group (p < 0.05). There were no significant differences in intraocular hypertension and NVG numbers between the two groups. Visual acuity in both groups improved after PPV surgery, reaching the highest level in the 3rd month after the operation. Conclusions: IVC before PPV can reduce the level of VEGF-A in the vitreous body and reduce surgical complications.