title: The use of contact lenses by U.S. civilian pilots.
abstract: BACKGROUND
  Since 1976, the use of contact lenses by civilian pilots has been permitted to correct distant vision for obtaining a Federal Aviation Administration (FAA) aeromedical certificate. This study examined the civil airman population's experience with contact lens use for a 30-year period (1967 to 1997).
  
  
  METHODS
  Population totals for airmen who carried pathology codes 161 (contact lens) and 158 (orthokeratology) from January 1, 1967 through December 31, 1997 were used to calculate prevalence rates by class of medical certificate and age. The National Transportation Safety Board and FAA databases were queried to determine if contact lens use had contributed to aviation mishaps.
  
  
  RESULTS
  The prevalence of contact lens use grew faster for first-class medical certificate holders and airmen > or = 40 years of age during the period. The frequency of airmen with orthokeratology increased by 23 times in a 10-year period. Reports from five aviation accidents and one incident suggested that contact lens use was a contributing factor in these mishaps.
  
  
  CONCLUSIONS
  Professional pilots and older airmen were found to be more inclined to use contact lenses. The increasing use of contact lenses and the rapid changes in contact lens technology warrant continued monitoring to ensure aviation safety.
authors.affiliation: Federal Aviation Administration, Civil Aerospace Medical Institute, Vision Research Team, Oklahoma City, Oklahoma 73125, USA. van.nakagawara@faa.gov
authors.forename: Van B
authors.initials: VB
authors.lastname: Nakagawara
authors.forename: Kathryn J
authors.initials: KJ
authors.lastname: Wood
authors.forename: Ron W
authors.initials: RW
authors.lastname: Montgomery
mesh_terms: D000328:Adult; D000337:Aerospace Medicine; D001359:Aviation / Q000706:statistics & numerical data*; D003261:Contact Lenses / Q000706:statistics & numerical data*; D006801:Humans; D015995:Prevalence; D014481:United States; D014786:Vision Disorders / Q000453:epidemiology / Q000628:therapy; D015351:Vision Screening / Q000331:legislation & jurisprudence / Q000592:standards; D014792:Visual Acuity