title: Frictional resistance sheds light on the multicomponent nature of nasal obstruction: a combined in vivo and computational fluid dynamics study.
abstract: Exploring nasal flow contributes to better understanding of pathophysiological functions of nasal cavities. We combined the rhinomanometry measurements of 11 patients and computational fluid dynamics (CFD) simulations in 3 nasal airway models to dissect the complex mechanisms that determine nasal flow obstruction: spatial complexity and pressure-dependent deformability of nasal airways. We quantified spatial complexity by calculating longitudinal variations of hydraulic diameter, perimeter and area of nasal cavities, and their impact on flow characteristics by examining the longitudinal variations of the kinetic energy coefficient and the kinetic to potential energy ratio. Airway distensibility variably affected in vivo pressure-flow relationships through the appearance of flow-limitation patterns characterized by maximum flow and/or flow plateau. We quantified deformability and spatial complexity effects on nasal airway resistance by normalizing all data with averaged reference parameters. The results show that discrepancies in nasal flow resistances reflect airway deformability and geometrical complexity, and thereby constitute a framework to better characterize nasal obstruction.
authors.affiliation: Inserm, U955, Equipe 13, Cell and Respiratory Mechanics Department, 8, rue du Général Sarrail, F-94010 Créteil Cedex, France. bruno.louis@inserm.fr
authors.forename: Bruno
authors.initials: B
authors.lastname: Louis
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Papon
authors.forename: Céline
authors.initials: C
authors.lastname: Croce
authors.forename: Georges
authors.initials: G
authors.lastname: Caillibotte
authors.forename: Gabriela
authors.initials: G
authors.lastname: Sbirlea-Apiou
authors.forename: André
authors.initials: A
authors.lastname: Coste
authors.forename: Redouane
authors.initials: R
authors.lastname: Fodil
authors.forename: Daniel
authors.initials: D
authors.lastname: Isabey
mesh_terms: D000403:Airway Resistance / Q000502:physiology*; D003198:Computer Simulation; D006801:Humans; D021621:Imaging, Three-Dimensional; D008954:Models, Biological; D009296:Nasal Cavity / Q000502:physiology*; D015508:Nasal Obstruction / Q000473:pathology* / Q000503:physiopathology*; D017711:Nonlinear Dynamics; D011312:Pressure; D025363:Rhinomanometry; D014057:Tomography, X-Ray Computed
keywords: Nasal airway model; Nasal compliance; Nasal resistance; Rhinomanometry