Long-term results of vitreous surgery for proliferative diabetic retinopathy

In order to study long-term anatomical and functional results the authors evaluated the data from 260 patients who underwent pars plana vitrectomy for proliferative diabetic retinopathy. Indications for surgery were: vitreous hemorrhage, 68 eyes (26.2%); vitreous hemorrhage & tractional retinal detachment, 84 eyes (32.3%); tractional retinal detachment, 82 eyes (31.5%); and combined tractional-rhegmatogenous retinal detachment, 26 eyes (10%). In 118 eyes vitreoretinal surgery was combined with silicone-oil tamponade. The retina was completely attached posterior to a scleral buckle in 251 eyes (96%) at the time of the last examination. After a follow-up period of at least 12 months in a group of patients with vitreous hemorrhage, visual acuity improved in 88% of the eyes. Visual acuity was better than 0.5 in 31% of eyes. In group of eyes with nonresorbing vitreous hemorrhage & tractional retinal detachment visual acuity improved in 52% of eyes. Visual acuity improved in 76% of eyes with tractional retinal detachment and in 81% of eyes with combined tractional & rhegmatogenous retinal detachment. When comparing the latest postoperative visual acuity to visual acuity after three months postoperatively, visual acuity was unchanged in 88%, in 10% it became worse and in 3 cases (1%) became better. In the postoperative period, recurrent vitreous hemorrhage occurred in 33 (13%) eyes, reproliferation in 12 eyes. Cataract developed in 45 of 168 phakic eyes. If postoperative visual acuity before cataract formation was good, extracapsular cataract extraction with posterior chamber intraocular lens implantation was performed. Otherwise simple intra or extracapsular cataract extraction was performed. In 19 cases cataract operation was performed together with silicone oil extraction. Neovascular glaucoma developed postoperatively in 15 eyes (6%). Retinal detachment occurred postoperatively in 21 eyes (8%). In 15 eyes the retina was successfully reattached after additional operations.