FSI models were constructed for each mouse using two- and six-month MRI scans. Two domains are required for the FSI simulations: the fluid domain, given by the vessel lumen, and the solid domain, representing the aortic wall. A 3D model of the fluid domain was generated from MRI scans. Scans were segmented using image segmentation and model generation in
SimVascular[26 (
link)], with supplemental editing in
Meshmixer (Autodesk, Inc.). The 3D model included the brachiocephalic trunk, the left common carotid, and the left subclavian artery.
Because the aortic wall is too thin to measure directly from the MR images, the aortic wall was generated by extruding the lumen wall outward. The mouse-specific unloaded wall thickness was based on experimental measurement for the ascending aortic region shown in
Table 1 and was treated as constant over the length of the aorta.
A tetrahedral mesh was created using the TetGen mesh generator that is embedded in
SimVascular [27 ]. The mesh included both the solid and the fluid domains, with matching nodes at the interface between the domains to satisfy the kinematic and dynamic boundary conditions at the interfaces.
Bazzi M.S., Balouchzadeh R., Pavey S.N., Quirk J.D., Yanagisawa H., Vedula V., Wagenseil J.E, & Barocas V.H. (2022). Experimental and mouse-specific computational models of the Fbln4SMKO mouse to identify potential biomarkers for ascending thoracic aortic aneurysm. Cardiovascular engineering and technology, 13(4), 558-572.