title: A retrospective comparison of efficacy and safety of 680 consecutive lasik treatments for high myopia performed with two generations of flying-spot excimer lasers.
abstract: OBJECTIVE
  To compare the visual refractive outcome and complication of laser in situ keratomileusis (LASIK) carried out with a Carl Zeiss-Meditec MEL-70 Excimer laser and a MEL-80 laser for treatment of high myopia.
  
  
  METHODS
  Journal records of 680 consecutive eyes that underwent LASIK with a Schwind Supratome microkeratome and a MEL-70 Excimer laser (Group A), or a Moria M2 microkeratome and a MEL-80 Excimer laser (Group B) were reviewed. Manifest refraction, uncorrected and best spectacle-corrected visual acuity (BSCVA), corneal topography and central corneal thickness (CCT) were recorded before and 3 months after treatment. Pre- and postoperative complications, visual and refractive outcome and frequency of retreatments were registered.
  
  
  RESULTS
  Mean preoperative spherical equivalent refraction was -8.52 dioptres (-5.50- -18 dioptres), and the mean attempted laser correction was -8.02 dioptres (-5.50- -11 dioptres). Three months after LASIK, the average treatment error (difference between achieved and attempted correction) was 1.20 (SD=1.19) dioptres of under correction in Group A and 0.52 (SD=1.00) dioptres in Group B. Four eyes lost more than two lines of BSCVA (0.6%). In 110 eyes (16%), a re-LASIK procedure was performed to reduce remaining myopia after the primary procedure.
  
  
  CONCLUSIONS
  Laser in situ keratomileusis treatment for high myopia can effectively reduce high degrees of myopia. Under correction was observed in both treatment groups but Group B has a slightly better predictability. Significant loss of BSCVA occurs infrequently after LASIK for even considerable grades of myopia (0.6% in each group).
authors.affiliation: Department of Ophthalmology, Aarhus University Hospital, Aarhus, Denmark. lol7576@yahoo.com
authors.forename: Lola
authors.initials: L
authors.lastname: Gazieva
authors.forename: Mette Hjuler
authors.initials: MH
authors.lastname: Beer
authors.forename: Kim
authors.initials: K
authors.lastname: Nielsen
authors.forename: Jesper
authors.initials: J
authors.lastname: Hjortdal
mesh_terms: D000328:Adult; D003319:Corneal Stroma / Q000601:surgery; D005260:Female; D006801:Humans; D007431:Intraoperative Complications; D020731:Keratomileusis, Laser In Situ / Q000295:instrumentation*; D054018:Lasers, Excimer / Q000009:adverse effects / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D047728:Myopia, Degenerative / Q000503:physiopathology / Q000601:surgery*; D011183:Postoperative Complications; D012029:Refraction, Ocular / Q000502:physiology; D012189:Retrospective Studies; D013524:Surgical Flaps; D016896:Treatment Outcome; D014792:Visual Acuity / Q000502:physiology; D055815:Young Adult