title: Results of a 1-year comparative study of Zyoptix Tissue-Sparing and conventional Planoscan LASIK treatments.
abstract: OBJECTIVE
  To determine the efficacy, stability and higher order aberrations (HOAs) following Zyoptix Tissue-Sparing (TS) and conventional Planoscan LASIK.
  
  
  METHODS
  A prospective study was conducted on myopic patients. The Technolas 217z laser and XP microkeratome (Bausch & Lomb) were used. Patients were matched for age, pupil size, optical zone, ablation depth and preoperative HOAs. UCVA, MRSE and HOAs were analysed preoperatively and 3 and 12 months postoperatively.
  
  
  RESULTS
  35 eyes underwent conventional and 31 eyes TS LASIK. 3 months postoperatively, all eyes in the both groups had UCVA < or =20/30 with good stability at 1 year. The mean RMS of total HOA increased significantly 3 months postoperatively in the conventional (1.49 factor increase) and TS LASIK groups (1.84 factor increase) and remained stable at 12 months.
  
  
  CONCLUSIONS
  TS LASIK induced a greater increase in HOA than conventional Planoscan LASIK. This may be attributable to the smaller blend zone in TS treatments.
authors.affiliation: The Mater Private Hospital, Dublin, Ireland.
authors.forename: Caitriona
authors.initials: C
authors.lastname: Kirwan
authors.forename: Michael
authors.initials: M
authors.lastname: O'Keefe
mesh_terms: D000328:Adult; D005500:Follow-Up Studies; D006801:Humans; D020731:Keratomileusis, Laser In Situ / Q000295:instrumentation* / Q000379:methods*; D008875:Middle Aged; D009216:Myopia / Q000601:surgery*; D011183:Postoperative Complications / Q000517:prevention & control; D011446:Prospective Studies; D012030:Refractive Errors; D012984:Software; D016896:Treatment Outcome; D014792:Visual Acuity; D055815:Young Adult