To study the anatomical and functional resu lts obtained from 72 eyes of 69 patients who underwent pars plana vitrectomy for severe proliferative diabetic retinopathy. Indications for pars plana vitrectomy were: vitreous hemorrhage in 37 eyes (51.39%), tractional retina detachment in 15 eyes (20.83%), vitreous hemorrhage and tractional retina detachment in 16 eyes (22.22%), and combined tractional-rhegmatogenous retin a detachment in 4 eyes (5.56%). Relief of the traction from peripheral fibrovascular membranes was obtained with an encircling scleral buckle in 41 eyes (56.94%) and delamination, segmentation or membrane peeling in 51 eyes (70.83%). In 42 eyes (58.33%), the surgery was combined with silicone-oil tamponade.
After the follow-up of 6 to 17 months (mean 9.01±3.43 months) the visual acuity was 1/10 or higher in 6.94% of the eyes. The visual acuity improved in 51.39% of the eyes, was unchanged in 36.11%, and became worse in 12.50%. The retina was completely attached in 54 eyes (75%) at the time of the last examination. In the postoperative period, vitreous hemorrhage occurred in 7 eyes (9.72%), ocular hypertension o ccurred in 8 eyes (11.11%) and cataract developed in 7 eyes (9.72%).
Pars plana vitrectomy for severe fibrovascular proliferation differs fro m conventional approaches to diabetic retinopathy in that relief of retina traction must be attained by scleral buckling and adequate dissection of peripheral fibrovascular tissue. Anatomic success rate tended to be better than functional success rate in high-risk severe proliferative diabetic retinopathy. So when severe fibrovascular proliferation occurs, complete removal of anteroposterior traction could only improve the anatomic success rate of the vitrectomy in most of the cases.
Keywords: Severe proliferative diabetic retinopathy, pars plana vitrectomy, anatomical results, visual outcome