title: A randomized comparison of pupil-centered versus vertex-centered ablation in LASIK correction of hyperopia.
abstract: OBJECTIVE
  To compare visual and optical outcomes of pupil-centered vs vertex-centered ablation in patients undergoing laser-assisted in situ keratomileusis (LASIK) for hyperopia.
  
  
  METHODS
  Randomized, double-masked, prospective, single-center trial.
  
  
  METHODS
  
  
  
  METHODS
  Institutional practice.
  
  
  METHODS
  Sixty eyes of 30 patients with low and moderate hyperopia. Intervention procedure: Eyes underwent LASIK (Allegretto excimer laser). In 30 eyes, the ablation was centered on the pupil, while in the 30 other eyes the ablation was centered on the corneal reflex.
  
  
  METHODS
  Primary outcome measure was the safety index. Main secondary outcome measures were efficacy index, manifest refraction, uncorrected visual acuity, best spectacle-corrected visual acuity (BCVA), and ocular high-order aberrations for a 6-mm pupil size.
  
  
  RESULTS
  At 3 months postoperatively, the safety index was 0.99 ± 0.04 in the pupil-centered group and 0.99 ± 0.08 in the vertex-centered group (P = .97). The efficacy index was also similar for both groups: 0.96 ± 0.05 in pupil-centered eyes and 0.93 ± 0.09 in vertex-centered eyes (P = .31). Optical aberrations were similar for pupil-centered and vertex-centered eyes. Considering only eyes showing large pupil decentration, we found a tendency for better visual results in favor of pupil-centered eyes in terms of safety index and a slight but significant increase of coma in vertex-centered eyes.
  
  
  CONCLUSIONS
  LASIK is an effective procedure for treatment of hyperopia. Pupil-centered and vertex-centered treatments provide similar visual and optical outcomes. However, in eyes showing large temporal pupil decentration, pupil-centered ablation seemed to produce a lower amount of coma and, as a consequence, a reduced loss of BCVA compared with vertex-centered patients.
authors: Ophthalmology Department, Purpan Hospital, Toulouse, France. vincesoler@yahoo.fr
authors: Vincent
authors: V
authors: Soler
authors: Antonio
authors: A
authors: Benito
authors: Pauline
authors: P
authors: Soler
authors: Claire
authors: C
authors: Triozon
authors: Jean-Louis
authors: JL
authors: Arné
authors: Virginie
authors: V
authors: Madariaga
authors: Pablo
authors: P
authors: Artal
authors: François
authors: F
authors: Malecaze
mesh_terms: D057128:Aberrometry; D001767:Blinking / Q000502:physiology*; D003315:Cornea / Q000503:physiopathology / Q000601:surgery*; D057108:Corneal Wavefront Aberration / Q000175:diagnosis; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D006956:Hyperopia / Q000503:physiopathology / Q000601:surgery*; D020731:Keratomileusis, Laser In Situ / Q000009:adverse effects / Q000379:methods*; D054018:Lasers, Excimer / Q000009:adverse effects / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011680:Pupil / Q000502:physiology*; D012029:Refraction, Ocular / Q000502:physiology; D014792:Visual Acuity / Q000502:physiology