Treatment of severe proliferative diabetic retinopathy (PDR) may require the use of silicone oil for long-term retinal tamponade to prevent recurrent retinal detachment. Massive bleeding during surgery before proper release of traction and peri-silicone oil proliferation after surgery were major causes of surgical failure. The likelihood of reproliferation rises in the presence of significant preretinal blood. It is therefore crucial to reduce intraoperative and postoperative preretinal hemorrhage in complicated diabetic vitrectomy with silicone oil infusion.