Blood flow CFD simulation on a cerebral artery of a stroke patient

Abstract

Abstract The purpose of this paper is to conduct a numerical simulation of the stroke patient's cerebral arteries and investigate the flow parameters due to the presence of stenosis. The computational fluid dynamics (CFD) simulations are based on simplified and realistic cerebral artery models. The seven simplified models (benchmarks) include straight cylindrical vessels with idealized stenosis with variable d/D (0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1). The realistic model of the cerebral artery is based on magnetic resonance imaging (MRI) for patient-specific cerebral arteries. The simulation for the realistic model of the cerebral artery is performed at boundary conditions measured by ultrasonography of the input and the output flow profiles (velocity and pressure). The obtained CFD results of the benchmarks are validated with actual data from the literature. Furthermore, a previous vascular contraction is assumed to be exist and the effect of this contraction area ratio on the blood flow regime is discussed and highlighted. Furthermore, CFD results show that a certain vascular contraction area critically affects the blood flow which shows increasing the wall shear stress WSS at the stenosis site. An increase in the blood velocity and vortex appears after the contraction zone, this lead to vessel occlusion and strokes. Article highlights The pressure drop across the arterial contraction is reduced when the area ratio d/D is increased. In some cases, the vortex can prevent blood flow from crossing, this leads to vessel occlusion especially at low d/D The WSS near the contraction area is high. Increasing the WSS can cause embolism that leads to lead to vessel occlusion.

Keywords

• Hemodynamics
• Cerebral arteries stenosis
• Computational fluid dynamics
• Wall shear stress