Randomized comparison of diode laser photocoagulation versus cryotherapy for threshold retinopathy of prematurity: Seven-year outcome

PURPOSE: To report the structural and functional outcomes at a minimum of 7 years postmenstrual age after randomized treatment of threshold retinopath y of prematurity with laser ablation or cryotherapy. METHODS: Nineteen patients were entered into a prospective, randomized prot ocol, in which one eye received cryotherapy, while the other eye received d iode laser photocoagulation. Asymmetric eyes were randomly assigned. Two pa tients have died, and seven were no longer available for 7 year outcome exa minations, leaving 10 children for analysis. RESULTS: Six males and four females with a mean birth cs eight of 631 g and a mean gestational age of 24.8 weeks were examined. Eight were symmetrical cases and treated in both eyes. Of these, there were six concordant and tw o discordant structural outcomes. The laser-treated eyes had the favorable outcome in each instance. The geometric mean visual acuity of the paired ey es after laser photocoagulation was 20/33, and after cryotherapy it was 20/ 133 (P = .03). The mean refractive error was -6.50 diopters after laser pho tocoagulation and -8.25 diopters after cryotherapy (P = .27), although one of the cryotherapy eyes could not be refracted because of phthisis. CONCLUSIONS: Laser photocoagulation appears to be associated with a structu ral and functional outcome at least as good as cryotherapy 7 years after th erapy. Visual acuity and refractive error data suggest that laser photocoag ulation may have an advantage over cryotherapy (Am J Ophthalmol 2001;132:76 -80. (C) 2001 by Elsevier Science Inc. All rights reserved).