Computational fluid dynamic simulation of human carotid artery bifurcation based on anatomy and volumetric blood flow rate measured with magnetic resonance imaging

Abstract

Blood flow patterns and local hemodynamic parameters have been widely associated with the onset and progression of atherosclerosis in the carotid artery. Assessment of these parameters can be performed noninvasively using cine phase-contrast (PC) magnetic resonance imaging (MRI). In addition, in the last two decades, computational fluid dynamics (CFD) simulation in three dimensional models derived from anatomic medical images has been employed to investigate the blood flow in the carotid artery. This study developed a workflow of a subject-specific CFD analysis using MRI to enhance estimating hemodynamics of the carotid artery. Time-of-flight (TOF) MRI scans were used to construct three-dimensional computational models. PC-MRI measurements were utilized to impose the boundary condition at the inlet and a 0-dimensional lumped parameter model was employed for the outflow boundary condition. The choice of different viscosity models of blood flow as a source of uncertainty was studied, by means of the axial velocity, wall shear stress, and oscillatory shear index. The sequence of workflow in CFD analysis was optimized for a healthy subject using PC-MRI. Then, a patient with carotid artery stenosis and its hemodynamic parameters were examined. The simulations indicated that the lumped parameter model used at the outlet gives physiologically reasonable values of hemodynamic parameters. Moreover, the dependence of hemodynamics parameters on the viscosity models was observed to vary for different geometries. Other factors, however, may be required for a more accurate CFD analysis, such as the segmentation and smoothness of the geometrical model, mechanical properties of the artery’s wall, and the prescribed velocity profile at the inlet.

Four-Dimensional Flow Magnetic Resonance Imaging for Assessment of Velocity Magnitudes and Flow Patterns in The Human Carotid Artery Bifurcation: Comparison with Computational Fluid Dynamics

“…This study was performed with laminar flow analysis and blood was simulated with a density of 1066 kg/meter 3 and a dynamic viscosity of 0.0035 pascal-seconds (Pa•s). The CFD simulation process of human carotid artery was as described previously [20]. The value of flow velocity obtained from the 4D flow MRI program was inputted to the inlet at the CCA, and the pressure values were inputted to the outlets at the ICA and ECA.…”

Simulation Analysis of Blood Flow in Arteries of the Human Arm

“…The algorithm to incorporate both a Newtonian fluid physics model and a linear PC-MRI signal model was proposed by Rispoli et al 6 for carotid bifurcation, where regularized blood flow gained the best results. Gharahi et al 7 simulated human carotid artery bifurcation based on anatomy and volumetric blood flow rate measured with PC-MRI. They found the limitation of PC-MRI to be its non-precise measurement of blood velocity near artery walls, although CFD simulation gave better results.…”

Computational fluid dynamic study on effect of Carreau-Yasuda and Newtonian blood viscosity models on hemodynamic parameters

“…However, it has a range from zero to infinite shear rate and only the values in realistic range will approximate the non-Newtonian behavior. Also, the power law index is usually selected so that the model replicates the shear thinning behavior in hemodynamic simulations [33]. The Casson model takes into account both the shear thinning behavior and the yield stress of blood.…”