To evaluate the safety and efficacy of intravitreal conbercept after vitrectomy for the management of early-stage proliferative diabetic retinopathy (PDR).

Hypothesis: intravitreal conbercept therapy may promote functional and anatomic recovery from PDR. intravitreal conbercept therapy may be a useful and safe method for improving visual outcomes of surgery for early-stage PDR.

The drug conbercept (an anti-vascular endothelial growth factors) was recently made available for management of early prolific diabetic retinopathy, but its safety and efficacy still require study. Therefore, the aim is to evaluate the safety and efficacy of intravitreal conbercept after vitrectomy for the management of early proliferative diabetic retinopathy.The patients were randomly assigned (25 eyes each group) to either treatment group and control after they provided informed consent. The treatment group received intravitreal conbercept (10 mg/mL, 0.5 mg) immediately after surgery, while the control group did not.

At the time of study enrollment, physical examinations, best-corrected visual acuity (BCVA), intraocular pressure and central retinal thickness will be measured and fundoscopy be performed.

The patients are going to be followed up for at least 6 months via BCVA measurement, fundoscopy, OCT, physical examinations and postoperative complications

Inclusion Criteria:

1. We enrolled 50 eyes from 50 patients that were affected by VH as a consequence of early active PDR.
2. Patients with non-clearing VH and fibrocellular proliferation without TRD who underwent PPV at Tianjin Medical University Eye Hospital were included in the study.

Exclusion Criteria:

1. A history of previous PPV;
2. Severe intraoperative complications
3. Postoperative silicone oil tamponade;
4. Menstruation;
5. Stroke, a thromboembolic event, or myocardial infarction in the previous
6. months contraindicating the withdrawal of anti-platelet and anti-coagulant medications.