title: Factors influencing the changes in coma-like aberrations after myopic laser in situ keratomileusis.
abstract: OBJECTIVE
  To assess factors affecting changes in coma-like aberrations after myopic laser in situ keratomileusis (LASIK).
  
  
  METHODS
  We retrospectively examined 91 eyes of 48 patients undergoing LASIK (mean patient age ± standard deviation, 29.6 ± 8.1 years; gender, 29 male and 19 female; manifest refraction, -4.76 ± 1.42 diopters). We quantitatively assessed the values of coma-like aberrations for 4-mm and 6-mm pupils using a Hartmann-Shack aberrometer before and 3 months after surgery. Multiple regression analysis was used to assess the relevant factors of the changes in coma-like aberrations.
  
  
  RESULTS
  The mean changes in coma-like aberrations for 4-mm and 6-mm pupils were 0.08 ± 0.09 μm and 0.31 ± 0.30 μm, respectively. Explanatory variables relevant to the changes in coma-like aberrations were, in order of influence, amount of spherical equivalent correction (partial regression coefficient B = 0.022, p <0.001 for a 4-mm pupil, B = 0.090, p <0.001 for a 6-mm pupil), and surgical technique (B = -0.062, p = 0.01 for a 4-mm pupil, B = -0.169, p = 0.03 for a 6-mm pupil). No significant correlation was seen with other clinical factors such as age, gender, astigmatism correction, mean keratometric readings, central corneal thickness, or eye tracking (with or without).
  
  
  CONCLUSIONS
  High myopic eyes requiring larger amounts of laser correction and eyes undergoing conventional LASIK tend to induce more coma-like aberration after surgery. Wavefront-guided LASIK may be a better surgical approach for preventing the induction of coma-like aberrations, especially in eyes with high myopia.
authors.affiliation: Department of Ophthalmology, University of Kitasato School of Medicine, Sagamihara, Kanagawa, Japan. kamiyak-tky@umin.ac.jp
authors.forename: Kazutaka
authors.initials: K
authors.lastname: Kamiya
authors.forename: Kyoko
authors.initials: K
authors.lastname: Umeda
authors.forename: Akihito
authors.initials: A
authors.lastname: Igarashi
authors.forename: Wakako
authors.initials: W
authors.lastname: Ando
authors.forename: Kimiya
authors.initials: K
authors.lastname: Shimizu
mesh_terms: D000293:Adolescent; D000328:Adult; D019781:Corneal Topography; D057108:Corneal Wavefront Aberration / Q000209:etiology* / Q000503:physiopathology; D005260:Female; D006801:Humans; D020731:Keratomileusis, Laser In Situ; D054018:Lasers, Excimer / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D009216:Myopia / Q000503:physiopathology / Q000601:surgery*; D011183:Postoperative Complications; D012029:Refraction, Ocular / Q000502:physiology; D012189:Retrospective Studies; D012307:Risk Factors; D014792:Visual Acuity / Q000502:physiology; D055815:Young Adult