title: Sonotubometry: a useful tool to measure intra-individual changes in eustachian tube ventilatory function.
abstract: OBJECTIVE
  To determine whether intra-individual changes in eustachian tube (ET) function induced by local application of a histamine phosphate solution can be detected using an improved sonotubometer.
  
  
  METHODS
  The function of the ET was measured with a revised sonotubometer before and after histamine was applied to the nasopharyngeal ostium of the ET.
  
  
  METHODS
  Tertiary referral hospital.
  
  
  METHODS
  Twenty-five otologically healthy adults.
  
  
  METHODS
  A histamine phosphate solution with a concentration of 16 mg/mL was applied to the nasopharyngeal ostium of the ET using a pressure nebulizer.
  
  
  METHODS
  The number of openings during 10 acts of swallowing. This outcome value could range from 0 to 10. The number of ET openings before and after histamine application was compared.
  
  
  RESULTS
  The mean number of ET openings dropped dramatically: from 8.4 before application of histamine to 2.7 after application. This difference was statistically significant; there was a mean difference of 5.6 (95% confidence interval, 4.4-6.9; P < .001).
  
  
  CONCLUSIONS
  Sonotubometry is capable of detecting intra-individual changes in ET function and may therefore be a very useful tool in monitoring and/or clinical research of ET dysfunction or function.
authors: Department of Otorhinolaryngology, Radboud University Nijmegen Medical Centre, PO Box 9101, 6500 HB Nijmegen, The Netherlands. n.vanheerbeek@kno.umcn.nl
authors: Niels
authors: N
authors: van Heerbeek
authors: Stijn J C
authors: SJ
authors: van der Avoort
authors: Gerhard A
authors: GA
authors: Zielhuis
authors: Cor W R J
authors: CW
authors: Cremers
mesh_terms: D000161:Acoustic Stimulation / Q000295:instrumentation*; D000328:Adult; D003679:Deglutition / Q000502:physiology; D005064:Eustachian Tube / Q000378:metabolism / Q000502:physiology*; D005260:Female; D006632:Histamine / Q000031:analogs & derivatives* / Q000493:pharmacokinetics; D018494:Histamine Agents / Q000493:pharmacokinetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D013016:Sound
chemical_list: D018494:Histamine Agents; D006632:Histamine; C027556:histamine phosphate