title: An assessment of intraocular pressure change in healthy subjects during air flight.
abstract: OBJECTIVE
  To investigate the effect of air flight on intraocular pressure (IOP).
  
  
  METHODS
  Baseline IOP of 25 healthy volunteers was measured at a ground level of 1760 feet above sea level (ASL) using Tono-Pen XL. Measurements were repeated after reaching an altitude of 19,000 feet and then on the second hour during a routine flight. Cabin pressure was kept around 8000 feet. IOP measurement was repeated after landing (3.5 hr after taking off). Change in the IOP was evaluated.
  
  
  RESULTS
  Mean +/- SD IOP was 14.2 +/- 2.7 mmHg at ground level and was 14.0 +/- 2.2 mmHg after gaining maximum altitude (p = 0.78). Mean IOP dropped to 12.3 +/- 2.5 mmHg on the second hour of flight and 12.0 +/- 1.7 mmHg after landing. Decrease in IOP on the second hour (13.4%, p = 0.005) and after landing (15.7%, p = 0.001) were significant.
  
  
  CONCLUSIONS
  IOP significantly decreased on the second hour measurements during a routine flight, and this change was sustained after landing.
authors.affiliation: GATA School of Medicine, Ankara, Turkey. atillabayer@hotmail.com
authors.forename: Atilla
authors.initials: A
authors.lastname: Bayer
authors.forename: Fatih Mehmet
authors.initials: FM
authors.lastname: Mutlu
authors.forename: Fahrettin
authors.initials: F
authors.lastname: Akay
authors.forename: Mehmet Zeki
authors.initials: MZ
authors.lastname: Bayraktar
mesh_terms: D000328:Adult; D000401:Aircraft; D000531:Altitude; D005260:Female; D006801:Humans; D007429:Intraocular Pressure; D008297:Male; D012016:Reference Values; D013997:Time Factors