title: Grating visual acuity results in the early treatment for retinopathy of prematurity study.
abstract: OBJECTIVE
  To compare grating (resolution) visual acuity at 6 years of age in eyes that received early treatment (ET) for high-risk prethreshold retinopathy of prematurity (ROP) with that in eyes that underwent conventional management (CM).
  
  
  METHODS
  In a randomized clinical trial, infants with bilateral, high-risk prethreshold ROP (n = 317) had one eye undergo ET and the other eye undergo CM, with treatment only if ROP progressed to threshold severity. For asymmetric cases (n = 84), the high-risk prethreshold eye was randomized to ET or CM.
  
  
  METHODS
  Grating visual acuity measured at 6 years of age by masked testers using Teller acuity cards.
  
  
  RESULTS
  Monocular grating acuity results were obtained from 317 of 370 surviving children (85.6%). Analysis of grating acuity results for all study participants with high-risk prethreshold ROP showed no statistically significant overall benefit of ET (18.1% vs 22.8% unfavorable outcomes; P = .08). When the 6-year grating acuity results were analyzed according to a clinical algorithm (high-risk types 1 and 2 prethreshold ROP), a benefit was seen in type 1 eyes (16.4% vs 25.2%; P = .004) undergoing ET, but not in type 2 eyes (21.3% vs 15.9%; P = .29).
  
  
  CONCLUSIONS
  Early treatment of eyes with type 1 ROP improves grating acuity outcomes, but ET for eyes with type 2 ROP does not. APPLICATION TO CLINICAL MEDICINE: Type 1 eyes should be treated early; however, based on acuity results at 6 years of age, type 2 eyes should be cautiously monitored for progression to type 1 ROP. Trial Registration clinicaltrials.gov Identifier: NCT00027222.
authors: Velma
authors: V
authors: Dobson
authors: Graham E
authors: GE
authors: Quinn
authors: C Gail
authors: CG
authors: Summers
authors: Robert J
authors: RJ
authors: Hardy
authors: Betty
authors: B
authors: Tung
authors: William V
authors: WV
authors: Good
mesh_terms: D000465:Algorithms; D002648:Child; D017679:Cryotherapy; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D017075:Laser Coagulation; D008297:Male; D012178:Retinopathy of Prematurity / Q000503:physiopathology* / Q000601:surgery*; D013997:Time Factors; D014787:Vision Tests / Q000295:instrumentation; D014792:Visual Acuity / Q000502:physiology*