Objective: To report the structural and visual outcomes of eyes in which retinal detachment developed from retinopathy of prematurity (ROP) in the Early Treatment of Retinopathy of Prematurity (ETROP) Study. Method: Infants in the ETROP Study with bilateral high-risk prethreshold ROP had 1 eye randomized to early treatment, with the fellow eye managed conventionally. In infants with asymmetric disease, the eye with high-risk prethreshold ROP was randomized to early treatment or conventional management. When a retinal detachment was detected, observation or vitreoretinal surgery (ie, scleral buckling and/or vitrectomy) was provided at the discretion of the individual investigator. At 9 months corrected age, retinal examinations were performed and visual acuities were assessed by masked testers using grating acuity. Results: The ETROP Study enrolled 401 patients with high-risk prethreshold ROP. Retinal detachments occurred in 89 eyes of 63 patients. Follow-up was available for 78 eyes of 56 patients. The detachments were bilateral in 21 patients (38%) and were classified as stage 4A in 30 eyes, stage 4B in 14 eyes, and stage 5 in 16 eyes. Detachments were not classified in 18 eyes. Twelve eyes of 11 patients were observed and 66 eyes of 52 patients underwent vitreoretinal surgery. Attachment of the macula at 9 months persisted or was achieved in 17 (30%) of 56 eyes after vitrectomy with or without scleral buckle, in 6 (60%) of 10 eyes after scleral buckle only, and in 2 (17%) of 12 eyes followed up without surgery. Favorable visual acuity (≥1.85 cycles/degree) was found in 13 (17%) of the 78 eyes. All 6 eyes that maintained normal visual acuity (≥3.70 cycles/degree) had a stage 4A detachment (1 of 6 managed by observation, 3 of 6 by scleral buckle, and 2 of 18 by vitrectomy). Eleven eyes with stage 5 detachment underwent vitreoretinal surgery, resulting in 6 with no light perception, 3 with light perception only, and 2 with detection of only the low vision card. Conclusions: In the ETROP Study, the outcome of retinal detachment owing to ROP was generally poor. Vitreoretinal surgery for retinal detachment was associated with macular attachment in 16 of 48 eyes. Normal acuity was maintained after surgical repair of stage 4A retinal detachment in 5 (21%) of 24 eyes. Vitreoretinal surgery for stage 5 disease was associated with some structural successes but poor functional outcomes. Objective: To report the structural and visual outcomes of eyes in which retinal detachment developed from retinopathy of prematurity (ROP) in the Early Treatment of Retinopathy of Prematurity (ETROP) Study. Method: Infants in the ETROP Study with bilateral high-risk prethreshold ROP had 1 eye randomized to early treatment, with the fellow eye managed conventionally. the eye with high-risk prethreshold ROP was randomized to early treatment or conventional management. When a retinal detachment was detected, observation or vitreoretinal surgery ( ie, scleral buckling and / or vitrectomy) was provided at the discretion of the individual investigator. At 9 months corrected age, retinal examinations were performed and visual acuities were assessed by masked testers using grating acuity. Results: The ETROP Study enrolled 401 patients with high-risk prethreshold ROP. Retinal detachments occurred in 89 eyes of 63 patients. Follow-up was available for 78 eyes of 56 patients. The detachments were bilateral in 21 patients (38%) and were classified as stage 4A in 30 eyes, stage 4B in 14 eyes, and stage 5 in 16 eyes. were observed and 52 eyes under 52 patients underwent vitreoretinal surgery. Attachment of the macula at 9 months persisted or was achieved in 17 (30%) of 56 eyes after vitrectomy with or without scleral buckle, in 6 (60%) of 10 eyes after Favorable visual acuity (≥1.55 cycles / degree) was found in 13 (17%) of the 78 eyes. All 6 eyes that maintained normal visual acuity (≥3.70 cycles / degree) had a stage 4A detachment (1 of 6 managed by observation, 3 of 6 by scleral buckle, and 2 of 18 by vitrectomy). Eleven eyes with stage 5 detachment underwent vitreoretinal surgery, resulting in 6 with no light perception, 3 with light perception only, and 2 with detection of only the low vision card. C onclusions: In the ETROP Study, the outcome of retinal detachment due to ROP was generally poor. Vitreoretinal surgery for retinal detachment was associated with macular attachment in 16 of 48 eyes. Normal acuity was maintained after surgical repair of stage 4A retinal detachment in 5 ( 21%) of 24 eyes. Vitreoretinal surgery for stage 5 disease was associated with some structural successes but poor functional outcomes.