Treatment of middle ear ventilation disorders: sheep as animal model for stenting the human Eustachian tube--a cadaver study

PLoS One. 2014 Nov 24;9(11):e113906. doi: 10.1371/journal.pone.0113906. eCollection 2014.

Abstract

Eustachian tube disorders can lead to chronic otitis media with consecutive conductive hearing loss. To improve treatment and to develop new types of implants such as stents, an adequate experimental animal model is required. As the middle ear of sheep is known to be comparable to the human middle ear, the dimensions of the Eustachian tube in two strains of sheep were investigated. The Eustachian tube and middle ear of half heads of heathland and blackface sheep were filled with silicone rubber, blended with barium sulfate to induce X-ray visibility. Images were taken by digital volume tomography. The tubes were segmented, and a three-dimensional model of every Eustachian tube was generated. The lengths, diameters and shapes were determined. Additionally, the feasibility of endoscopic stent implantation and fixation was tested in cadaver experiments. The length of the tube between ostium pharyngeum and the isthmus and the diameters were comparable to published values for the human tube. The tube was easily accessible through the nose, and then stents could be implanted and fixed at the isthmus. The sheep appears to be a promising model for testing new stent treatments for middle ear ventilation disorders.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cadaver
  • Cone-Beam Computed Tomography
  • Ear Diseases / diagnosis
  • Ear Diseases / surgery*
  • Ear, Middle / pathology
  • Ear, Middle / surgery*
  • Endoscopy
  • Eustachian Tube / pathology
  • Eustachian Tube / surgery*
  • Hearing Loss, Conductive / prevention & control
  • Humans
  • Middle Ear Ventilation / methods
  • Models, Animal
  • Otitis Media / prevention & control
  • Reproducibility of Results
  • Sheep
  • Sheep Diseases / diagnosis
  • Sheep Diseases / surgery*
  • Stents

Grants and funding

This study was supported by the German Federal Ministry of Education and Research (BMBF) as part of REMEDIS: Higher quality of life through novel micro-implants (FKZ 03IS2081E). URL: www.bmbf.de; http://remedis.med.uni-rostock.de/. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.