title: Functional optical zone after myopic LASIK as a function of ablation diameter.
abstract: OBJECTIVE
  To analyze spherical aberrations in patients who had myopic laser in situ keratomileusis (LASIK) with different optical zones and varying degrees of attempted corrections.
  
  
  METHODS
  Laser Refractive Center, University of California, Los Angeles, USA.
  
  
  METHODS
  This retrospective analysis comprised 78 eyes of 56 consecutive patients who had LASIK for myopia with the Alcon LADARVision excimer laser. The preoperative and 3-month postoperative functional optical zones (FOZs), a measure of spherical aberrations, were assessed in each eye. The change in FOZs was analyzed by size of the primary optical zone and degree of attempted correction.
  
  
  RESULTS
  The mean preoperative FOZ was 6.1 mm +/- 0.6 (SD) and the mean 3-month FOZ, 5.2 +/- 1.0 mm. The mean decrease was 0.9 +/- 1.0 mm (P < .0001). The mean decreases were 0.005 +/- 0.7 mm, 0.7 +/- 0.9 mm, and 1.6 +/- 0.9 mm in the low, moderate, and high attempted correction groups, respectively (P < .05), and 1.3 +/- 0.9 mm, 1.2 +/- 1.0 mm, 0.5 +/- 1.3 mm, and 0.3 +/- 0.7 mm in optical zone groups of 6.0 to 6.5 mm, 6.6 to 7.0 mm, 7.1 to 7.5 mm, and 7.6 to 8.0 mm, respectively (P < .05).
  
  
  CONCLUSIONS
  Larger optical zones had fewer postoperative spherical aberrations. Higher attempted corrections had larger increases in spherical aberrations. Larger treatment diameters minimized postoperative spherical aberrations.
authors.affiliation: Boxer Wachler Vision Institute, Beverly Hills, California 90210, USA.
authors.forename: Richard L
authors.initials: RL
authors.lastname: Nepomuceno
authors.forename: Brian S
authors.initials: BS
authors.lastname: Boxer Wachler
authors.forename: Ryan
authors.initials: R
authors.lastname: Scruggs
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015350:Contrast Sensitivity / Q000502:physiology; D003315:Cornea / Q000502:physiology* / Q000601:surgery; D019781:Corneal Topography; D005260:Female; D006801:Humans; D020731:Keratomileusis, Laser In Situ; D008297:Male; D008875:Middle Aged; D009216:Myopia / Q000503:physiopathology* / Q000601:surgery*; D012189:Retrospective Studies; D014792:Visual Acuity / Q000502:physiology*