title: Application of magnetic resonance (MR) imaging for the development and validation of computational fluid dynamic (CFD) models of the rat respiratory system.
abstract: Computational fluid dynamic (CFD) models of the respiratory system provide a quantitative basis for extrapolating the localized dose of inhaled materials and improving human health risk assessments based upon inhalation studies conducted in animals. Nevertheless, model development and validation have historically been tedious and time-consuming tasks. In recognition of this, we previously reported on the use of proton (1H) magnetic resonance (MR) imaging for visualizing nasal-sinus passages in the rat, and for speeding computational mesh generation. Here, the generation and refinement of meshes for rat nasal airways are described in more detail and simulated airflows are presented. To extend the CFD models to the complete respiratory tract, three-dimensional (3D) 1H MR imaging of rat pulmonary casts was also utilized to construct pulmonary airway meshes using procedures developed for the nasal airways. Furthermore, the feasibility of validating CFD predictions with MR was tested by imaging hyperpolarized 3He gas at physiological flow rates in a straight pipe with a diameter comparable to the rat trachea. Results from these diverse studies highlight the potential utility of MR imaging not only for speeding CFD development but also possibly for model validation.
authors.affiliation: Pacific Northwest National Laboratory, Richland, Washington 99352, USA. kevin.minard@pnl.gov
authors.forename: Kevin R
authors.initials: KR
authors.lastname: Minard
authors.forename: Daniel R
authors.initials: DR
authors.lastname: Einstein
authors.forename: Richard E
authors.initials: RE
authors.lastname: Jacob
authors.forename: Senthil
authors.initials: S
authors.lastname: Kabilan
authors.forename: Andrew P
authors.initials: AP
authors.lastname: Kuprat
authors.forename: Charles A
authors.initials: CA
authors.lastname: Timchalk
authors.forename: Lynn L
authors.initials: LL
authors.lastname: Trease
authors.forename: Richard A
authors.initials: RA
authors.lastname: Corley
mesh_terms: D000818:Animals; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008953:Models, Anatomic; D008954:Models, Biological; D051381:Rats; D017207:Rats, Sprague-Dawley; D015203:Reproducibility of Results; D015656:Respiratory Mechanics; D012137:Respiratory System / Q000033:anatomy & histology*; D012212:Rheology