Abstract:Objective To study the factors affecting postoperative vitreous hemorrhage (PVH) after pars plana vitrectomy (PPV) and prognostic analysis in patients with proliferative diabetic retinopathy (PDR).Methods The clinical data of 156 patients with PDR in the Affiliated Hospital of Nantong University from February 2019 to February 2022 were collected retrospectively. All patients underwent PPV, and were divided into PVH group and non-PVH group according to whether PVH occurred 6 months after surgery. The clinical characteristics of the two groups were compared, and factors affecting the occurrence of PVH were analyzed by the multivariable Logistic regression model. Besides, the prognosis of the patients was compared between the two groups.Results The incidence of PVH within 6 months after PPV was 13.46% (21/156) among patients with PDR. There was no significant difference between the two groups in sex composition, age, course of diabetes mellitus, history of laser eye surgery, presence of iris neovascularization (NVI), systolic blood pressure (SBP), diastolic blood pressure (DBP), visual acuity, grayscale representation of visual field, macular thickness, duration of PPV, intraoperative laser photocoagulation treatment and intraoperative use of filling materials (P > 0.05). The percentage of stage VI PDR, proportion of proliferative retinal traction, level of glycosylated hemoglobin (HbAlc), and postoperative intraocular pressure in the PVH group were significantly higher than those in the non-PVH group (P < 0.05). The multivariable Logistic regression analysis showed that the PDR stage [O^R = 4.591 (95% CI: 1.997, 10.550) ], presence of proliferative retinal traction [O^R = 3.736 (95% CI: 1.626, 8.586)], the level of HbAlc [O^R = 4.293 (95% CI: 1.868, 9.867) ] and postoperative intraocular pressure [O^R = 3.666 (95% CI: 1.595, 8.425) ] were all factors affecting the occurrence of PVH after PPV in PDR patients (P < 0.05). The prognosis of the non-PVH group was better than that of the PVH group (P < 0.05).Conclusions Factors affecting the occurrence of PVH after PPV in PDR patients include the PDR stage, combination of proliferative retinal traction, the level of HbAlc, and postoperative intraocular pressure, while PVH may affect the prognosis of visual acuity.