title: Four-year to seven-year outcomes of advanced surface ablation with excimer laser for high myopia.
abstract: OBJECTIVE
  We aimed to evaluate and compare outcomes after photorefractive keratectomy with cooling (cPRK) and laser-assisted subepithelial keratectomy (LASEK) for high myopia.
  
  
  METHODS
  This was a retrospective, single-masked follow-up study of patients treated for myopia between 2007 and 2009 with cPRK or LASEK, using a high-frequency flying-spot excimer laser with eye-tracker (MEL80; Carl Zeiss, Jena, Germany). One eye of each patient was randomly chosen for analysis. Re-treated eyes were excluded.
  
  
  RESULTS
  Forty-six cPRK patients and 35 LASEK patients were included. Spherical equivalent averaged -7.69 ± 1.47 diopters (D) in cPRK eyes and -7.98 ± 2.06 D in LASEK eyes (p = 0.31) before surgery. The average follow-up time was 4.6 years in cPRK patients and 6.0 years in LASEK patients (p < 0.05). At final follow-up, no cPRK eyes and one LASEK eye (p = 0.46) had lost two lines of corrected distance visual acuity (CDVA). No eyes had significant haze at final follow-up, although trace haze was found in four cPRK eyes and six LASEK eyes (p = 0.44). However, at 6 weeks after surgery, zero cPRK eyes and nine LASEK eyes (p < 0.05) had significant haze. At final follow-up, 63 % of cPRK eyes and 35 % of LASEK eyes (p = 0.17) were within ±1.0 D of intended refraction. Finally, 100 % of cPRK patients and 92 % of LASEK patients (p = 0.87) were satisfied or very satisfied with the surgery at final follow-up.
  
  
  CONCLUSIONS
  cPRK and LASEK seemed safe and with high patient satisfaction 4 to 7 years after surgery for high myopia. However, cPRK was more effective than LASEK in reducing initial significant corneal haze.
authors.affiliation: Department of Ophthalmology, Odense University Hospital, Sdr. Boulevard 29, 5000, Odense C, Denmark, rasha10@student.sdu.dk.
authors.forename: Rasmus Søgaard
authors.initials: RS
authors.lastname: Hansen
authors.forename: Niels
authors.initials: N
authors.lastname: Lyhne
authors.forename: Jakob
authors.initials: J
authors.lastname: Grauslund
authors.forename: Keea Treu
authors.initials: KT
authors.lastname: Grønbech
authors.forename: Anders Højslet
authors.initials: AH
authors.lastname: Vestergaard
mesh_terms: D000328:Adult; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D020731:Keratomileusis, Laser In Situ; D054018:Lasers, Excimer / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D009216:Myopia / Q000503:physiopathology / Q000601:surgery*; D017060:Patient Satisfaction; D018903:Photorefractive Keratectomy; D012189:Retrospective Studies; D016037:Single-Blind Method; D016896:Treatment Outcome; D014792:Visual Acuity / Q000502:physiology; D055815:Young Adult