title: Contrast sensitivity after laser in situ keratomileusis. one-year follow-up.
abstract: OBJECTIVE
  To determine whether contrast sensitivity measurement, a more sensitive test of visual function than visual acuity, better characterizes visual outcomes after laser in situ keratomileusis (LASIK).
  
  
  METHODS
  Hong Kong Laser Eye Centre, Hong Kong, China.
  
  
  METHODS
  Contrast sensitivity was monitored in 41 LASIK patients for 1 year. Seven spatial frequencies (0.3, 0.8, 1.5, 3.4, 6.9, 10.3, and 20.5 cpd) were tested with 15 sequences per spatial frequency, and a staircase technique was used for target presentation.
  
  
  RESULTS
  There was a general depression in the contrast sensitivity function after LASIK; 1.5 cpd and 3.4 cpd were the most affected frequencies. Recovery took at least 6 months. The reduction in contrast sensitivity was greater for higher amounts of myopia.
  
  
  CONCLUSIONS
  The post-LASIK nonpermanent depression in contrast sensitivity was probably due to optical factors.
authors.affiliation: Centre for Myopia Research, Department of Optometry and Radiography, The Hong Kong Polytechnic University , Hong Kong, China.
authors.forename: Jay W W
authors.initials: JW
authors.lastname: Chan
authors.forename: Marion H
authors.initials: MH
authors.lastname: Edwards
authors.forename: George C
authors.initials: GC
authors.lastname: Woo
authors.forename: Victor C P
authors.initials: VC
authors.lastname: Woo
mesh_terms: D000328:Adult; D015350:Contrast Sensitivity / Q000502:physiology*; D003319:Corneal Stroma / Q000503:physiopathology / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D020731:Keratomileusis, Laser In Situ / Q000009:adverse effects*; D008297:Male; D009216:Myopia / Q000503:physiopathology / Q000601:surgery*; D014786:Vision Disorders / Q000209:etiology / Q000503:physiopathology*