TY - JOUR
T1 - Fluid-structure interaction modeling of blood flow and cerebral aneurysm
T2 - Significance of artery and aneurysm shapes
AU - Torii, Ryo
AU - Oshima, Marie
AU - Kobayashi, Toshio
AU - Takagi, Kiyoshi
AU - Tezduyar, Tayfun E.
N1 - Funding Information:
The authors thank Dr. Motoharu Hayakawa (Fujita Health University, Japan) and Toshiba Medical, Inc. for providing the CT images and image processing software ALATOVIEW. The authors are also grateful to Professor Motoaki Sugawara (Tokyo Women’s Medical University, Japan) for his help in acquiring the velocity waveform. Part of this research was carried out within the framework of the project “Frontier Simulation Software for Industrial Science (FSIS)” and “Revolutionary Simulation Software (RSS)”, supported by the IT program of the Ministry of Education, Culture, Sports, Science and Technology (MEXT). The last author was supported in part by a Seed Grant from the Gulf Coast Center for Computational Cancer Research funded by John & Ann Doerr Fund for Computational Biomedicine.
PY - 2009/9/15
Y1 - 2009/9/15
N2 - Because wall shear stress (WSS) is known to play an important role in initiation, growth and rupture of cerebral aneurysm, predicting the hemodynamic forces near the aneurysmal site helps with understanding aneurysms better. Earlier research reports indicate that the WSS around the aneurysmal site has a significant relationship with the vascular and aneurysm morphology. It was also shown statistically that the aneurysm shape (aspect ratio) is an indicator of rupture risk in cerebral aneurysm. In this study, fluid-structure interaction (FSI) modeling of a ruptured aneurysm, two unruptured aneurysms at the middle cerebral artery (MCA) bifurcation, and a MCA bifurcation without aneurysm is carried out using vascular geometries reconstructed from CT images. We use pulsatile boundary conditions based on a physiological flow velocity waveform and investigate the relationship between the hemodynamic forces and vascular morphology for different arteries and aneurysms. The results are compared with the results obtained for the rigid arterial wall to highlight the role of FSI in the patient-specific modeling of cerebral aneurysm. The results show that the interaction between the blood flow and arterial deformation alters the hemodynamic forces acting on the arterial wall and the interaction strongly depends on the individual aneurysm shapes. Flow impingement on the arterial wall plays a key role in determining the interaction and hemodynamic forces. When the blood flow impinges strongly on the wall, the maximum WSS tends to decrease due to the flow-wall interaction. When the blood flows straight into an aneurysm, the flow and the resulting WSS patterns are altered both qualitatively and quantitatively. When the blood in the aneurysm is nearly stagnant, a slow flow is induced by the wall motion, which raises the minimum WSS on the aneurysmal wall. The results reinforce the importance of FSI in patient-specific analysis of cerebral aneurysms.
AB - Because wall shear stress (WSS) is known to play an important role in initiation, growth and rupture of cerebral aneurysm, predicting the hemodynamic forces near the aneurysmal site helps with understanding aneurysms better. Earlier research reports indicate that the WSS around the aneurysmal site has a significant relationship with the vascular and aneurysm morphology. It was also shown statistically that the aneurysm shape (aspect ratio) is an indicator of rupture risk in cerebral aneurysm. In this study, fluid-structure interaction (FSI) modeling of a ruptured aneurysm, two unruptured aneurysms at the middle cerebral artery (MCA) bifurcation, and a MCA bifurcation without aneurysm is carried out using vascular geometries reconstructed from CT images. We use pulsatile boundary conditions based on a physiological flow velocity waveform and investigate the relationship between the hemodynamic forces and vascular morphology for different arteries and aneurysms. The results are compared with the results obtained for the rigid arterial wall to highlight the role of FSI in the patient-specific modeling of cerebral aneurysm. The results show that the interaction between the blood flow and arterial deformation alters the hemodynamic forces acting on the arterial wall and the interaction strongly depends on the individual aneurysm shapes. Flow impingement on the arterial wall plays a key role in determining the interaction and hemodynamic forces. When the blood flow impinges strongly on the wall, the maximum WSS tends to decrease due to the flow-wall interaction. When the blood flows straight into an aneurysm, the flow and the resulting WSS patterns are altered both qualitatively and quantitatively. When the blood in the aneurysm is nearly stagnant, a slow flow is induced by the wall motion, which raises the minimum WSS on the aneurysmal wall. The results reinforce the importance of FSI in patient-specific analysis of cerebral aneurysms.
KW - Aneurysm morphology
KW - Cerebral aneurysm
KW - Fluid-structure interaction
KW - Wall shear stress
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U2 - 10.1016/j.cma.2008.08.020
DO - 10.1016/j.cma.2008.08.020
M3 - Article
AN - SCOPUS:70049104371
SN - 0374-2830
VL - 198
SP - 3613
EP - 3621
JO - Computer Methods in Applied Mechanics and Engineering
JF - Computer Methods in Applied Mechanics and Engineering
IS - 45-46
ER -