Simulating pulsatile flow: towards understanding MRI sequences targeting microvascular fluid-structure interactions

Motivation: MRI is increasingly used to investigate vascular pathology in neurodegenerative disease. The origin of the MRI signal, however, often remains elusive. This study models pulsatile blood flow aiming to characterize vascular pulsation’s impact on MRI signal formation in advanced sequences. Goal(s): To create a realistic model of pulsatile blood flow in microvasculature. Approach: Static and pulsatile flow are simulated in a simplified and a more realistic synthetically generated vessel model using 1D approximations of governing equations. Results: Pulsatile flow simulations in simplified networks with realistic inflow wave forms yield realistic deformation characteristics. Realistic pressure and flow distributions are achieved in extensive microvascular networks. Impact: By providing realistic voxel-scale vascular simulation models capable of quantifying physiological parameters such as CBV and vessel deformation due to pulsatility, contribution of microvascular pulsations to MRI signal and cerebral waste clearance may be explored in the future.