Indication of vitreous surgery for proliferative diabetic retinopathy

We reviewed the outcome of vitreous surgery for diabetic retinopathy in 122 eyes of 94 cases during a one-year period. The series comprised macular tractional retinal detachment 36 eyes, extramacular tractional retinal detachment 32 eyes, vitreous hemorrhage 43 eyes, and diffuse macular edema 11 eyes. Six months after surgery, the visual acuity increased by 2 lines or more in 76 eyes (68%), remained unchanged in 22 eyes (20%), and deteriorated in 13 eyes (12%). The final visual acuity was below 20/200 in 33 eyes (29%), between 20/200 and 20/30 in 72 eyes (57%), and better than 20/30 in 17 eyes (15%). Cases of macular tractional retinal detachment comprised 6 out of 13 eyes of deteriorated visual acuity and 15 out of 33 eyes with final visual acuity of below 20/200. The findings show that vitreous surgery for proliferative diabetic retinopathy had better be performed before tractional retinal detachment involves the macula.