Digital Lung

Project Title: Multiscale Simulation of Gas Flow Distribution in the Human Lung

Sponsored by the National Institute for Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health

Abstract:

The ultimate goal of the project is to develop a comprehensive computational fluid dynamics (CFD) model for pulmonary air flow that utilizes subject-specific airway geometries, spans spatial scales from the largest bronchial airways to alveolar sac, and employs a Computed Tomography (CT) data-driven, multistage approach to provide accurate predictions of regional ventilation and gas transport through the entire moving airway tree. The applications of the model include, but are not limited to, improving pharmaceutical aerosol drug delivery, predicting subject-specific regional ventilation for diagnosis of patterns related to pathologic changes in airway geometry and parenchyma.

This project aims to establish a novel collaboration between Drs Lin (PI), Hoffman (Co-PI; DPI & I-Clic Director), McLennan (Co-I), and Tawhai (Co-I), bringing together complementary expertise in modeling and validating fluid transport in the respiratory system at different scales. The team provides considerable strength in CFD techniques, integrative geometric modeling of pulmonary structures, experimentation and imaging over a range of scales in the pulmonary system, and pulmonary medicine. The ultimate goal of the project is to build a subject-specific digital lung model for predicting regional ventilation and gas transport in the healthy and disease-state human lungs in a CT and MRI dynamic-data-driven and multiscale setting.

This project also fits within the framework of two of the most significant ongoing research efforts in pulmonary science: the Lung Atlas and the International Union of Physiological Sciences (IUPS) Physiome Project. The Lung Atlas Project led by Dr. Hoffman aims to document airway geometry over four decades of age in healthy and diseased adult humans. The Physiome Project is a worldwide effort to provide a computational framework for understanding human physiology and to develop integrative models at all levels of biological organization, ranging from genes to the whole organism. Dr. Tawhai is the lead scientist in developing Lung Physiome. Dr. Lin will apply CFD techniques with advanced capabilities to achieve realistic representation of pulmonary flow in the deforming airways. Simulation results will be interpreted and related to clinical application by Dr. McLennan, who is a Pulmonary, Critical Care and Occupational Medicine faculty and doctor at the University of Iowa General Hospital and the national Chair of The Lung Image Database Consortium (LIDC).

The figure below shows the pressure contours of simulated airflow in the CT-based human lung model at the peak inspiration.