title: Respiratory flow in a realistic tracheostenosis model.
abstract: The possible mechanism of wheeze generation in tracheostenosis was identified by measuring inspiratory and expiratory flow in a "morphological and distensible" realistic tracheostenosis model. The shape of the model was based on CT (Computed Tomography) images of a patient that had tracheostenosis. A trachea consists of tracheal cartilage rings and smooth muscle. Spatial variation of wall distensibility was achieved in the model by varying the wall thickness based on the elastic modulus measured in pig airways. The spatial variation influenced the flow in the airway and the turbulence production rate decreased faster at smooth muscles. Using the model, we investigated the mechanism of wheeze generation by focusing on the turbulence intensity. The turbulence intensity in expiratory flow was about twice that in inspiratory flow, and larger vortices existed in post-stenosis in expiratory flow, and thus might contribute to wheeze generation.
authors.affiliation: Center for Life Science and Technology, School of Fundamental Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, 223-8522, Japan. sera@tani.sd.keio.ac.jp
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Sera
authors.forename: Sunao
authors.initials: S
authors.lastname: Satoh
authors.forename: Hirohisa
authors.initials: H
authors.lastname: Horinouchi
authors.forename: Koichi
authors.initials: K
authors.lastname: Kobayashi
authors.forename: Kazuo
authors.initials: K
authors.lastname: Tanishita
mesh_terms: D000818:Animals; D003198:Computer Simulation; D004548:Elasticity; D006801:Humans; D066298:In Vitro Techniques; D008954:Models, Biological; D009038:Motion; D009130:Muscle, Smooth / Q000503:physiopathology*; D012123:Pulmonary Ventilation / Q000502:physiology*; D012119:Respiration; D012135:Respiratory Sounds / Q000209:etiology / Q000503:physiopathology*; D013552:Swine; D014132:Trachea / Q000503:physiopathology*; D014135:Tracheal Stenosis / Q000150:complications / Q000503:physiopathology*