title: The effect of hyperbaric conditions on olfactory functions.
abstract: OBJECTIVE
  The aim of this study was to investigate the effect of increased atmospheric pressure (AP) on olfactory function.
  
  
  METHODS
  The present study included 40 healthy volunteers with no history of chronic rhinosinusitis and nasal polyposis. The experimental procedure consisted of two episodes: (a) baseline episode, with normal AP; 1 absolute atmosphere (atm abs) in a test room at sea level; (b) experimental episode, increased level of AP; 2.4 atm abs in the hyperbaric chamber. Sino-nasal outcome test-20, Trail Making Test A and olfactory testing were performed in each episodes.
  
  
  RESULTS
  The study group consisted of 23 men (57.5%) and 17 women (42.5%); the mean age of the study population was 38.7 +/- 9 years (range 23-58 years). The current investigation produced two major findings: (1) the mean of odor threshold scores was significantly increased in the hyperbaric condition when compared to the normobaric condition; (2) rather, there was no significant change in odor discrimination and identification scores in the hyperbaric condition.
  
  
  CONCLUSIONS
  Based on two measurements taken at two different barometric pressures and the same temperature and relative humidity, this study suggests that odor threshold scores increase under hyperbaric conditions.
authors.forename: Hakan
authors.initials: H
authors.lastname: Ay
authors.forename: Murat
authors.initials: M
authors.lastname: Salihoglu
authors.forename: Aytug
authors.initials: A
authors.lastname: Altundag
authors.forename: Hakan
authors.initials: H
authors.lastname: Tekeli
authors.forename: Ali
authors.initials: A
authors.lastname: Memis
authors.forename: Melih
authors.initials: M
authors.lastname: Cayonu
mesh_terms: D000328:Adult; D001274:Atmospheric Pressure; D005260:Female; D006801:Humans; D006813:Humidity; D006931:Hyperbaric Oxygenation; D008297:Male; D008875:Middle Aged; D055696:Olfactory Perception / Q000502:physiology*; D012684:Sensory Thresholds / Q000502:physiology; D012737:Sex Factors; D012903:Smell / Q000502:physiology*; D013696:Temperature; D055815:Young Adult