Numerical Simulation for Blood Flow - Microsurgery: Advances, Simulations, and Applications - page 193

5.4 Blood Flow Simulations for Internal Carotid

Artery

5.4.1 Introduction

According to the statistics published by the Ministry of Health
in Japan, one of three major causes of death is cerebral vascular
disturbance and more than 130,000 people die from this disease
every year. Most of subarachnoid hemorrhage (SAH) is said to arise
from the rupture of a brain aneurysm at bifurcation of cerebral
vessel. 3 Even if patients survive the rupture of a brain aneurysm,
their rehabilitation is impeded by the aftereffect. Therefore, SAH is a
very serious disease. However, the exact cause of SAH is still unclear.
This is because the interaction between endothelial cell functions
and hemodynamics stimulus is not well understood. Moreover,
parameters of artery, such as wall shear stress, blood pressure and
blood velocity are dificult to measure in vivo because cerebral vessels
are narrow and complicated. However, with the development of
computing capability, various sorts of parameters in cerebral vessels
are obtained in more details by numerical simulations. In recent
years, computational luid dynamics studies have actively attempted
to clarify the mechanism of cerebral vascular disease with the data
obtained from computed tomography (CT) and magnetic resonance
image (MRI). Flow dynamics of cerebral vessels were studied in
numerous experimental models and clinical studies. 4-9 As a result,
new indings from these researches help us make a guideline for
diagnosis of the cerebral vascular disease. In this research, luid
structure interaction (FSI) analysis in ICA model was carried out.

5.4.2 Studied Morphology

Arterial model was extracted from CT data and used as computational
model. This model is part of the ICA bifurcation. The shape of this
model is shown in Fig. 5.20. The length of the whole model is 65.8
mm and the diameter of the inlet is 6.0 mm, and the diameters of
two outlets are 3.35 and 3.09 mm, respectively. The thickness of this
arterial wall is assumed to be uniform and 0.3 mm. The mesh was
generated with unstructured grid as polyhedral cells to it shape