title: Femtosecond laser versus mechanical microkeratome: a retrospective comparison of visual outcomes at 3 months.
abstract: To compare the visual outcomes of LASIK procedures in which flaps were created with a femtosecond laser (IntraLase FS 60Hz, Abbott Medical Optics [AMO]) to procedures in which flaps were created with a mechanical microkeratome (Moria Evo3 One Use-Plus, Moria SA).
  
  
  
  A retrospective analysis was performed on 2000 eyes treated in 2008 for low myopia and astigmatism (sphere < -3.00 diopters [D]; cylinder < or = -0.75 D). The first 1000 consecutive eyes that had LASIK flaps created with a femtosecond laser were compared with the first 1000 consecutive eyes that had flaps created with a mechanical microkeratome. All eyes received wavefront-guided LASIK treatments performed with a VISX S4 IR Advanced CustomVue excimer laser (AMO). Refractive predictability, change in mean spherical equivalent refraction, postoperative uncorrected visual acuity (UCVA), and loss of best spectacle-corrected visual acuity (BSCVA) were compared at 1 day, 1 week, 1 month, and 3 months following surgery.
  
  
  
  The refractive accuracy was the same for both groups. At all time points measured, the percentage of eyes that achieved a postoperative UCVA of 20/20 or better was significantly higher in the femtosecond laser group than in the mechanical keratome group. Also, a higher percentage of eyes in the femtosecond laser group achieved a postoperative UCVA of 20/16 at 3 months. Finally, a lower percentage of eyes in the femtosecond laser group lost two or more lines of BSCVA at 1 week and 1 month postoperative.
  
  
  
  Creating LASIK flaps with the femtosecond laser resulted in faster visual recovery and better UCVA.
authors.affiliation: Optical Express, 5 Deerdykes Rd, Westfield, Cumbernauld G68 9HF, United Kingdom. meshatanna@opticalexpress.com
authors.forename: Mesha
authors.initials: M
authors.lastname: Tanna
authors.forename: Steven C
authors.initials: SC
authors.lastname: Schallhorn
authors.forename: Keith A
authors.initials: KA
authors.lastname: Hettinger
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001251:Astigmatism / Q000601:surgery; D003315:Cornea / Q000601:surgery*; D005260:Female; D006801:Humans; D020731:Keratomileusis, Laser In Situ / Q000379:methods*; D054018:Lasers, Excimer / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D009216:Myopia / Q000601:surgery*; D012029:Refraction, Ocular / Q000502:physiology; D012189:Retrospective Studies; D013524:Surgical Flaps; D014792:Visual Acuity / Q000502:physiology*; D055815:Young Adult