title: Effects of functional endoscopic sinus surgery on the acoustics of the sinonasal tract.
abstract: BACKGROUND
  Nasal and paranasal cavities are supposed to contribute substantially to the vocal tract resonator properties. However, their acoustical effects as well as the effects of sinus surgery on the voice remain unclear. In this work we investigate resonance phenomena of paranasal sinuses prior to and after various rhinosurgical procedures in cadaveric human sinonasal tracts and corresponding 3D casts.
  
  
  METHODS
  Nasal and paranasal cavities of formalin-preserved cadavers and corresponding 3D replicas were excited by sine-tone sweeps from an earphone placed in the epipharynx. The response was picked up by a microphone at the nostrils. Different FESS procedures were performed and the acoustical responses following excitation were recorded. The measured acoustical changes in the obtained transfer functions were then evaluated.
  
  
  RESULTS
  Marked low frequency dips were detected in the transfer functions when sinus cavities were included in the nasal resonator system. These dips showed a significant correlation with sinus volumes. Following FESS procedures they moved upwards in frequency depending on the extent of the surgical intervention.
  
  
  CONCLUSIONS
  The transfer functions obtained in cadaveric situs and 3D replicas showed dips at the resonance frequencies of the paranasal cavities. Marked acoustic effects in terms of increase in dip frequency following FESS procedures were reproducibly documented.
authors.affiliation: Dept. of Otorhinolaryngology, Head and Neck Surgery, Section Phoniatrics, Munich University Hospital, Munich, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Havel
authors.affiliation: Dept. of Otorhinolaryngology, Head and Neck Surgery, University Medical Center of Johannes Gutenberg University, Mainz, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Becker
authors.affiliation: ept. of Otorhinolaryngology, Head and Neck Surgery, Section Phoniatrics, Munich University Hospital, Munich, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Schuster
authors.affiliation: Dept. of Radiology, Munich University Hospital, Munich, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Johnson
authors.affiliation: Dept. of Computer Science, Friedrich-Alexander-University, Erlangen, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Maier
authors.affiliation: Dept. of Speech, Music and Hearing, School of Computer Science and Communication, KTH (Royal Institute of Technology), Stockholm, Sweden.
authors.forename: J
authors.initials: J
authors.lastname: Sundberg
mesh_terms: D002102:Cadaver; D004724:Endoscopy; D006801:Humans; D009296:Nasal Cavity / Q000000981:diagnostic imaging / Q000601:surgery; D010256:Paranasal Sinuses / Q000000981:diagnostic imaging / Q000601:surgery*; D013061:Speech Acoustics; D014057:Tomography, X-Ray Computed; D014833:Voice Quality / Q000502:physiology*