Computational Modeling with Fluid-Structure Interaction of the Severe M1 Stenosis Before and After Stenting

Abstract

PurposeImage-based computational models with fluid-structure interaction (FSI) can be used to perform plaque mechanical analysis in intracranial artery stenosis. We described a process in FSI study applied to symptomatic severe intracranial (M1) stenosis before and after stenting.Materials and MethodsReconstructed 3D angiography in STL format was transferred to Magics for smoothing of vessel surface and trimming of branch vessels and to HyperMesh for generating tetra volume mesh from triangular surface-meshed 3D angiogram. Computational analysis of blood flow in the blood vessels was performed using the commercial finite element software ADINA Ver 8.5. The distribution of wall shear stress (WSS), peak velocity and pressure was analyzed before and after intracranial stenting.ResultsThe wall shear stress distributions from Computational fluid dynamics (CFD) simulation with rigid wall assumption as well as FSI simulation before and after stenting could be compared. The difference of WSS between rigid wall and compliant wall model both in pre- and post-stent case is only minor except at the stenosis region. These WSS values were greatly reduced after stenting to 15~20 Pa at systole and 3~5 Pa at end-diastole in CFD simulation, which are similar in FSI simulations.ConclusionOur study revealed that FSI simulation before and after intracranial stenting was feasible despite of limited vessel wall dimension and could reveal change of WSS as well as flow velocity and wall pressure.

Pulse Wave Imaging in Carotid Artery Stenosis Human Patients in Vivo

“…The increased PWV around the plaque shown in Figures 2 and 3 is an observation that warrants further investigation through comparison with FSI simulations and phantom experiments. Most FSI studies of carotid arteries and stenosis have focused on wall shear stress, wall displacement, pressure, and flow velocity around the region of stenosis rather than wave propagation (Park et al, 2013;Tang et al, 2003;Teng et al, 2010).…”

A novel periodic boundary condition for computational hemodynamics studies

“…Instead, simulations are usually conducted on a subregion of interest having a certain boundary with the surrounding environment. [1][2][3][4] Particularly in hemodynamics studies for cardiovascular applications, assigning appropriate boundary conditions is challenging in unsteady conditions. [5][6][7][8] For simulating fully developed turbulent flows using large eddy simulation (LES) and direct numerical solution (DNS), periodic boundary conditions are particularly useful, in that the computational domain can be reduced considerably since even a generally unsteady turbulent flow can be approximated as repeating itself over a certain distance.…”

Flow Dynamics and Wall Shear Stresses in a Bifurcated Femoral Artery

“…Pre and post stent analysis was conducted at the bifurcation of intracranial artery. The velocity variations and the wall shear stresses are studied and compared to observe the effect of stent placement on flow dynamics at the bifurcation [7]. Hence, various medical conditions play a major role in atherosclerosis affected arteries.…”

“…The maximum change in shear stress observed around the posterior wall did not have much effect on age groups. However, the intima media thickness increases with age [7,8]. Profunda femoris, medial and lateral femoral circumflex are the bifurcated arteries from the femoral artery.…”