title: [Effect of ear-canal air pressure variation on tempanometry using a sweep-frequency probe tone].
abstract: OBJECTIVE
  By observing the effect of ear-canal pressure variation (ECPV) on tempanometry using a sweep-frequency probe tone, the roles of sweep-frequency tempanograms changes were studied.
  
  
  METHODS
  Tympanograms using a sweep-frequence probe tone were measured for 60 ears of 30 subjects at ECPV by admittance (Y), susceptance (B), conductance (G) with GSI33 middle ear analyzer.
  
  
  RESULTS
  There was not obviously difference about phase angle and resonance frequency among 3 measured conditions (P > 0.05); Resonance frequency became higher with higher positive pressure and lower with lower negative pressure in ear-canal; delta Y, delta G got lower with higher positive and lower negative pressure at resonance frequency; delta B is about 0 mmhos and almost didn't change with ECPV; phase angle decreased with higher positive or lower negative pressure. delta Y, delta G and delta phi were the highest at the peak pressure.
  
  
  CONCLUSIONS
  The higher the ear-canal positive pressure or the lower the negative pressure is, the higher the compliance and the lower the mass of middle ear is comparatively. The rub of middle ear is the lowest at normal peak pressure.
authors.affiliation: Department of Otolaryngology, Union Hospital, Tongji Medical University, Wuhan 430022.
authors.forename: H
authors.initials: H
authors.lastname: Wang
authors.forename: N
authors.initials: N
authors.lastname: Zhong
mesh_terms: D000158:Acoustic Impedance Tests; D000328:Adult; D000399:Air Pressure; D004424:Ear Canal / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male