Diabetic retinopathy is a significant source of visual morbidity in the adult population. Complications of diabetic retinopathy include ischemic maculopathy, macular edema, and sequelae of fibrovascular proliferation, such as vitreous hemorrhage (VH), tractional retinal detachment (TRD), and neovascular glaucoma.Pars plana vitrectomy (PPV) is traditionally performed for nonclearing VH, significant fibrovascular proliferation, refractive macular edema, and/or TRD, particularly if macula-involving. However, the pathogenesis is complex and multifactorial: Pro-infammatory cytokines and chemokines signifcantly contribute to the disease development and promote ischemic changes in the retina. Therefore, there is a potential role for intravitreal steroids in disease modifcation.

Diabetic retinopathy is a significant source of visual morbidity in the adult population. Complications of diabetic retinopathy include ischemic maculopathy, macular edema, and sequelae of fibrovascular proliferation, such as vitreous hemorrhage (VH), tractional retinal detachment (TRD), and neovascular glaucoma.Pars plana vitrectomy (PPV) is traditionally performed for nonclearing VH, significant fibrovascular proliferation, refractive macular edema, and/or TRD, particularly if macula-involving. However, the pathogenesis is complex and multifactorial: Pro-infammatory cytokines and chemokines signifcantly contribute to the disease development and promote ischemic changes in the retina. Therefore, there is a potential role for intravitreal steroids in disease modifcation. Corticosteroids reduce not only leukostasis and infammatory cytokine production, but also VEGF expression. Experimentally, corticosteroids potentially can influence both the inflammatory and the proliferative components of the PVR process via a variety of modes of administration without evidence of demonstrable retinal toxicity. So, this study is carried out for the purpose of investigating the efficacy of slow-release dexamethasone implant in proliferative vitreoretinopathy of postoperative proliferative diabetic retinopathy.

Inclusion Criteria:

• macula off treatment naive TRD second to PDR causing visual loss;
• treated by standardize PPV, endolaser and silicone oil tamponade with or without DEX implant at the end of the surgery within 12 months from diagnosis of TRD;
• Hba1c is less than 10% with type 1 or 2 diabetes mellitus

Exclusion Criteria:

• other concomitant ocular diseases that cause RD ( for example rhegmatogenous retinal detachment, exudative retinal detachment, other causes for TRD);
• any previous injection of DEX implant;
• abnormalities of the vitreoretinal interface, such as epiretinal membrane, vitreomacular traction without RD