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

Journal Article · Thu Dec 01 00:00:00 EST 2016 · Journal of Computational Physics

DOI:https://doi.org/10.1016/J.JCP.2016.08.039· OSTI ID:22622214

Miyawaki, Shinjiro; Choi, Sanghun ^[1]; Hoffman, Eric A. ^[2]; Lin, Ching-Long ^[1]

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1. IIHR – Hydroscience & Engineering, The University of Iowa, Iowa City, IA 52242 (United States)
2. Department of Biomedical Engineering, The University of Iowa, Iowa City, IA 52242 (United States)

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. - Highlights: • We developed a breathing human lung CFD model based on 4D-dynamic CT images. • The 4DCT-based breathing lung model is able to capture lung relative hysteresis. • A new boundary condition for lung model based on one static CT image was proposed. • The difference between lung models based on 4D and static CT images was quantified.

• OSTI ID: 22622214
• Journal Information: Journal of Computational Physics, Vol. 326; Other Information: Copyright (c) 2016 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-9991
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
97 MATHEMATICAL METHODS AND COMPUTING
ALGORITHMS
BIOMEDICAL RADIOGRAPHY
BOUNDARY CONDITIONS
CAT SCANNING
COMPARATIVE EVALUATIONS
COMPUTERIZED SIMULATION
DEFORMATION
DISTRIBUTION
FLUID MECHANICS
FLUIDS
FOUR-DIMENSIONAL CALCULATIONS
HYSTERESIS
IMAGES
INTERPOLATION
LUNGS
PRESSURE DROP
RESPIRATION
SURFACES