title: Higher-order aberrations and visual acuity after LASEK.
abstract: BACKGROUND
  To determine ocular higher-order aberrations (HOAs) in eyes with supernormal vision after myopic astigmatic laser subepithelial keratomileusis (LASEK) and to compare the findings with those in eyes with natural supernormal vision.
  
  
  METHODS
  Ocular HOAs were measured after LASEK in 20 eyes of 12 myopic astigmatic patients with postoperative uncorrected visual acuity (UCVA) of >20/16 (group 1). Patients who were included in the study had no visual symptoms like glare, halo or double vision. The measurements were taken 8.3 +/- 3 months after LASEK surgery. In group 2 ocular HOAs were examined in 20 eyes of 10 subjects with natural UCVA of >20/16 as a control. Measurements were taken across a pupil with a diameter of 4.0 mm and 6.0 mm. Root-mean-square (RMS) values of HOAs, Z(3)-1, Z(3)1, Z(4)0, Z(5)-1, Z(5)1 and Z(6)0 were analyzed.
  
  
  RESULTS
  The mean RMS values for each order were higher in group 1 when compared with group 2 at 4.0 mm and 6.0 mm pupil diameters. There was no statistically significant difference between groups in spherical and coma aberrations (P > 0.05). Mean RMS values for total HOAs were 0.187 +/- 0.09 microm at 4.0 mm and 0.438 +/- 0.178 microm at 6.0 mm pupil in group 1 and 0.120 +/- 0.049 microm at 4.0 mm and 0.344 +/- 0.083 microm at 6.0 mm pupil in group 2. The difference between groups in total HOAs was statistically significant at 4.0 mm and 6.0 mm pupil diameters (P < 0.05).
  
  
  CONCLUSIONS
  Ocular HOAs exist in eyes with supernormal vision. After LASEK, the amount of HOAs of the eye increases under both mesopic and photopic conditions. However the amount of HOA increase does not seem to be consistent with visual symptoms.
authors.affiliation: Department of Ophthalmology, Gazi University Medical School, Ankara, Turkey. bsekeryapan@yahoo.com
authors.forename: Berrak
authors.initials: B
authors.lastname: Urgancioglu
authors.forename: Kamil
authors.initials: K
authors.lastname: Bilgihan
authors.forename: Sertac
authors.initials: S
authors.lastname: Ozturk
mesh_terms: D001251:Astigmatism / Q000209:etiology / Q000503:physiopathology*; D005500:Follow-Up Studies; D006801:Humans; D049008:Keratectomy, Subepithelial, Laser-Assisted; D009216:Myopia / Q000601:surgery*; D011184:Postoperative Period; D012029:Refraction, Ocular / Q000502:physiology*; D016896:Treatment Outcome; D014792:Visual Acuity / Q000502:physiology*