title: Photorefractive keratectomy in children.
abstract: OBJECTIVE
  To evaluate photorefractive keratectomy (PRK) in pediatric patients who fail traditional methods of treatment for myopic anisometropic amblyopia and high myopia.
  
  
  METHODS
  Nonhospital surgical facility with follow-up in a hospital clinic setting.
  
  
  METHODS
  Photorefractive keratectomy was performed in 40 eyes of 27 patients. The patients were divided into 4 groups based on the type of myopia: myopic anisometropic amblyopia (15 eyes/13 patients), bilateral high myopia (20 eyes/10 patients), high myopia post-penetrating keratoplasty (3 eyes/2 patients), and combined corneal scarring and anisometropic amblyopia (2 eyes/2 patients). All procedures were performed under general anesthesia using the VISX 20/20 B laser and a multizone, multipass ablation technique. Appropriate corneal fixation was achieved with appropriate head positioning (turn and tilt) and an Arrowsmith fixation ring. Myopia was as high as -25.00 diopter (D) spherical equivalent (SE), but no treatment was for more than -17.50 D SE.
  
  
  RESULTS
  The mean SE decreased from -10.68 D to -1.37 D at 1 year, a mean change of -9.31 D. At 1 year, the mean best corrected visual acuity improved from 20/70 to 20/40 in the entire group. Forty percent of eyes were within +/-1.0 D of the targeted refraction. There was no haze in 59.5% of eyes. Three eyes initially had 3+ haze; 1 improved to 2+ and 2 required repeat PRK with significant haze reduction. Five eyes (3 patients) with greater than -17.00 D SE myopia before PRK (range -17.50 to -25.00 D) had 3.42 D more effect than predicted (range 0.50 to 5.50 D). A functional vision survey demonstrated a positive effect on the children's ability to function in their environments after the laser treatment.
  
  
  CONCLUSIONS
  Photorefractive keratectomy in children represents another method of providing long-term resolution of bilateral high myopia and myopic anisometropic amblyopia.
authors.affiliation: Alberta Children's Hospital, University of Calgary, Division of Ophthalmology, Calgary, Alberta, Canada.
authors.forename: William F
authors.initials: WF
authors.lastname: Astle
authors.forename: Peter T
authors.initials: PT
authors.lastname: Huang
authors.forename: Anna L
authors.initials: AL
authors.lastname: Ells
authors.forename: Robin G
authors.initials: RG
authors.lastname: Cox
authors.forename: Micheline C
authors.initials: MC
authors.lastname: Deschenes
authors.forename: Heather M
authors.initials: HM
authors.lastname: Vibert
mesh_terms: D000550:Amblyopia / Q000209:etiology / Q000601:surgery*; D015858:Anisometropia / Q000209:etiology / Q000601:surgery*; D002648:Child; D002675:Child, Preschool; D003315:Cornea / Q000601:surgery*; D005260:Female; D006801:Humans; D007223:Infant; D054018:Lasers, Excimer; D008297:Male; D009216:Myopia / Q000150:complications / Q000601:surgery*; D018903:Photorefractive Keratectomy / Q000379:methods*; D011446:Prospective Studies; D012029:Refraction, Ocular; D012449:Safety; D014792:Visual Acuity