The surgical results for 107 eyes that underwent vitrectomy for diabetic rhegmatogenous retinal detachment showed that the rhegmatogenous component of the detachment was successfully treated in 79 eyes (74%), although in 11 of the 79 eyes (14%) traction detachment of the macula persisted. At the final examinations, 57 eyes (53%) had improved visual acuities, 44 (41%) had worse visual acuities, and six (6%) were unchanged. Eleven eyes (10%) had final visual acuities of 20/40 or better, 48 eyes (45%) had final visual acuities of 20/50 to 20/800, and 48 eyes (45%) had final visual acuities worse than 20/800. Two preoperative factors were associated with a worse prognosis for achieving a final visual acuity of 20/800 or better: preoperative iris neovascularization (P less than .01) and preoperative detachment of the macula (P less than .05).