Morphological and functional properties of the conducting human airways investigated by in vivo computed tomography and in vitro MRI
Metadata only
Datum
2018-02Typ
- Journal Article
ETH Bibliographie
no
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Abstract
The accurate representation of the human airway anatomy is crucial for understanding and modeling the structure-function relationship in both healthy and diseased lungs. The present knowledge in this area is based on morphometric studies of excised lung casts, partially complemented by in vivo studies in which computed tomography (CT) was used on a small number of subjects. In the present study, we analyzed CT scans of a cohort of healthy subjects and obtained comprehensive morphometric information down to the seventh generation of bronchial branching, including airway diameter, length, branching angle, and rotation angle. Although some of the geometric parameters (such as the child-to-parent branch diameter ratio) are found to be in line with accepted values, for others (such as the branch length-to-diameter ratio) our findings challenge the common assumptions. We also evaluated several metrics of self-similarity, including the fractal dimension of the airway tree. Additionally, we used phase-contrast magnetic resonance imaging (MRI) to obtain the volumetric flow field in the three-dimensional-printed airway model of one of the subjects during steady inhalation. This is used to relate structural and functional parameters and, in particular, to close the power-law relationship between branch flow rate and diameter. The diameter exponent is found to be significantly lower than in the usually assumed Poiseuille regime, which we attribute to the strong secondary (i.e., transverse) velocity component. The strength of the secondary velocity with respect to the axial component exceeds the levels found in idealized airway models and persists within the first seven generations. Mehr anzeigen
Publikationsstatus
publishedExterne Links
Zeitschrift / Serie
Journal of Applied PhysiologyBand
Seiten / Artikelnummer
Verlag
American Physiological SocietyThema
airway morphometry; computed tomography; magnetic resonance imaging; structure-function relationshipOrganisationseinheit
09709 - Coletti, Filippo / Coletti, Filippo
ETH Bibliographie
no
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