Objective: To determine whether earlier treatment using ablation of the avascular retina in high-risk prethreshold retinopathy of prematurity (ROP) results in improved grating visual acuity and retinal structural outcomes compared with conventional treatment.Methods: Infants with bilateral high-risk prethreshold ROP (n=317) had one eye randomized to early treatment with the fellow eye managed conventionally (control eye). in asymmetric cases (n=84), the eye with high-risk prethreshold ROP was randomized to early treatment or conventional management. High risk was determined using a model based on the Multicenter Trial of Cryotherapy for Retinopathy of Prematurity natural history cohort. At a corrected age of 9 months, visual acuity was assessed by masked testers using the Teller acuity card procedure. At corrected ages of 6 and 9 months, eyes were examined for structural outcome. Outcomes for the 2 treatment groups of eyes were compared using chi(2) analysis, combining data for bilateral and asymmetric cases.Results: Grating acuity results showed a reduction in unfavorable visual acuity outcomes with earlier treatment, from 19.5% to 14.5% (P=.01). Unfavorable structural outcomes were reduced from 15.6% to 9.1% (P<.001) at 9 months. Further analysis supported retinal ablative therapy for eyes with type I ROP, defined as zone I, any stage ROP with plus disease (a degree of dilation and tortuosity of the posterior retinal blood vessels meeting or exceeding that of a standard photograph); zone I, stage 3 ROP without plus disease; or zone II, stage 2 or 3 ROP with plus disease. The analysis supported a wait-and-watch approach to type 2 ROP, defined as zone I, stage I or 2 ROP without plus disease or zone II, stage 3 ROP without plus disease. These eyes should be considered for treatment only if they progress to type I or threshold ROP.Conclusions: Early treatment of high-risk prethreshold ROP significantly reduced unfavorable outcomes to a clinically important degree. Additional analyses led to modified recommendations for the use of peripheral retinal ablation in. eyes with ROP. Long-term follow-up is being conducted to learn whether the benefits noted in the first year after birth will persist into childhood.

OBJECTIVE To evaluate outcomes at 10 years after randomization for eyes undergoing cryotherapy vs eyes serving as controls, for patients enrolled in the Multicenter Trial of Cryotherapy for Retinopathy of Prematurity (CRYO-ROP). METHODS The randomized cohort originally consisted of 291 preterm children with birth weights less than 1251 g who developed a defined threshold of ROP severity in one or both eyes. Patients with bilateral threshold ROP (n = 240) were randomly assigned to receive cryotherapy to one eye and no cryotherapy to the other eye. Those with ROP of less severity than threshold in the fellow eye ("asymmetric"; n = 51) were randomly assigned to cryotherapy or no cryotherapy in the eye with threshold ROP. Ten years later, a tester who was masked to treatment status of each eye measured distance and near visual acuity, with "unfavorable" outcome being 20/200 or worse. Patients also were evaluated by study-certified ophthalmologists who assessed ROP residua primarily in the posterior pole of the fundus, with unfavorable outcome being a posterior retinal fold or worse. RESULTS For the 247 children examined, both functional and structural primary outcomes showed fewer unfavorable outcomes in treated vs control eyes: 44.4% vs 62.1% (P<.001) for distance visual acuity and 27.2% vs 47.9% (P<.001) for fundus status. Near acuity results were similar to those for distance (42.5% vs 61.6%; P<.001). Total retinal detachments had continued to occur in control eyes, increasing from 38.6% at 5(1/2) years to 41.4% at 10 years, while treated eyes remained stable (at 22.0%). A previously disturbing subgroup trend that more control eyes than treated eyes had visual acuity of 20/40 or better (in the 5(1/2)-year report) was no longer present at 10 years; eyes that received cryotherapy were found at least as likely as control eyes to have 20/40 or better visual acuity. CONCLUSIONS At 10 years, eyes that had received cryotherapy were much less likely than control eyes to be blind. A previous trend for a higher proportion of sighted control eyes than sighted treated eyes to show acuity in the normal range was not confirmed. The results show long-term value from cryotherapy in preserving visual acuity in eyes with threshold ROP.

Objective: To evaluate outcome at 5 1/2 years after randomization in eyes that underwent cryotherapy and in control eyes of patients in the Multicenter Trial of Cryotherapy for Retinopathy of Prematurity.Design: During infancy, patients with bilateral threshold retinopathy of prematurity (ROP) were assigned to receive cryotherapy for one eye and no cryotherapy for the other eye. Those with threshold ROP in only one eye (asymmetric) were randomly assigned to cryotherapy or no cryotherapy for that eye. Then, 5 1/2 years later, testers who were masked to the treatment status of each eye measured the patients' monocular visual acuity by using the log of the minimum angle of resolution visual acuity chart that was used in the Early Treatment Diabetic Retinopathy Study. This was the most refined visual acuity testing yet performed on this cohort. Structural outcome was evaluated by participating ophthalmologists' assessment of ROP residua in the posterior pole of the fundus.Patients: Patients were 291 children who had been preterm infants with birth weights of less than 1251 g in whom threshold ROP had developed. Two hundred forty patients had bilateral threshold ROP, and 51 had threshold ROP in only one eye.Results: For the 234 children examined, both visual acuity and fundus structure showed a reduction in unfavorable outcomes in treated vs control eyes: 47.1% vs 61.7%, respectively (P<.005), for visual acuity and 26.9% vs 45.4%, respectively (P<.001), for fundus status. Detailed analysis uf visual acuity outcomes for all eyes revealed that while fewer treated eyes (31.5%) than control eyes (48%) were blind (P<.001), there was a slight trend toward fewer eyes with a visual acuity of 20/40 or better in the treated (13%) vs control (17%) groups (P=.19).Conclusions: The results support the long-term efficacy and safety of cryotherapy in the treatment of severe ROP. However, the data show preliminary evidence of a possible adverse effect of this treatment on visual acuity.