[One year outcomes of pars plana vitrectomy in proliferative diabetic retinopathy].

PURPOSE: To evaluate the 1-year results of pars plana vitrectomy for proliferative diabetic retinopathy. PATIENTS AND METHODS: Two hundred thirty six patients with proliferative diabetic retinopathy received primary vitreous surgery at Shiga University of Medical Science Hospital and had at least 1 year follow-up period. The indications for pars plana vitrectomy included vitreous hemorrhage in 140 eyes, extramacular tractional retinal detachment in 60 eyes, macular tractional retinal detachment in 24 eyes and combined tractional retinal detachment in 12 eyes. The visual acuity and changes in visual acuity at 1-year postoperatively were evaluated. Preoperative bevacizumab injection and postoperative visual outcomes were compared between patients treated with 20 gauge (20 G) surgery and with micro incision vitrectomy surgery (MIVS). RESULTS: The visual acuity improved by 3 lines or more in 166 eyes (70%) and remained unchanged in 56 eyes (24%); it decreased by 3 lines or more in 14 eyes (6%). Tractional retinal detachment in MIVS received more bevacizumab injections. MIVS systems achieved better visual results in the combined tractional retinal detachment group than 20 G system. CONCLUSION: Successful visual improvement at 1-year postoperatively was observed in eyes with proliferative diabetic retinopathy after pars plana vitrectomy. Results of this study may suggest the superior performance of MIVS for pars plana vitrectomy in proliferative diabetic retinopathy.