A 4DCT imaging-based breathing lung model with relative hysteresis

JOURNAL OF COMPUTATIONAL PHYSICS

卷:326

Article

Miyawaki, Shinjiro^1,6  Choi, Sanghun¹  Hoffman, Eric A.^3,4,5  Lin, Ching-Long^1,2 

[1] Univ Iowa, IIHR Hydrosci & Engn, Iowa City, IA 52242 USA

[2] Univ Iowa, Dept Mech & Ind Engn, Seamans Ctr 3131, Iowa City, IA 52242 USA

[3] Univ Iowa, Dept Biomed Engn, Iowa City, IA 52242 USA

[4] Univ Iowa, Dept Med, Iowa City, IA 52242 USA

[5] Univ Iowa, Dept Radiol, Iowa City, IA 52242 USA

[6] CH2M Hill Inc, 1100 NE Circle Blvd,Suite 300, Corvallis, OR 97330 USA

关键词: Multiscale;    Pulmonary airflow;    Relative hysteresis;    Regional ventilation;    Image registration;    4DCT;   

DOI  :  10.1016/j.jcp.2016.08.039

来源: Elsevier

【 摘 要 】

To reproduce realistic airway motion and airflow, the authors developed a deforming lung computational fluid dynamics (CFD) model based on four-dimensional (4D, space and time) dynamic computed tomography (CT) images. A total of 13 time points within controlled tidal volume respiration were used to account for realistic and irregular lung motion in human volunteers. Because of the irregular motion of 4DCT-based airways, we identified an optimal interpolation method for airway surface deformation during respiration, and implemented a computational solid mechanics-based moving mesh algorithm to produce smooth deforming airway mesh. In addition, we developed physiologically realistic airflow boundary conditions for both models based on multiple images and a single image. Furthermore, we examined simplified models based on one or two dynamic or static images. By comparing these simplified models with the model based on 13 dynamic images, we investigated the effects of relative hysteresis of lung structure with respect to lung volume, lung deformation, and imaging methods, i.e., dynamic vs. static scans, on CFD-predicted pressure drop. The effect of imaging method on pressure drop was 24 percentage points due to the differences in airflow distribution and airway geometry. (C) 2016 Elsevier Inc. All rights reserved.

【 授权许可】

Free