Simulation Of Blood Flow In Intracranial Aneurysm Via Computational Fluid Dynamics Modeling

The hemodynamics is closely related to the pathogenesis, evolution and rupture of intracranial aneurysm, which is one of the most serious human cardiovascular diseases. In this thesis, computational fluid dynamics (CFD) method is applying to simulate the pulastile blood flow in both statistical and patietent-specific aneurysm models. The effect of geometry factors and wall compliance on the hemodynamics was studied. The potential relationship between the hemodynamical factors such as velocity, WSS, OSI etc. was discussed in view of their influences on the evolution of cerebral aneurysm.In the first part of this thesis, a statistical ICA-PComA aneurysm model was generated based on clinic data. Both steady flow and unsteady flow were simulated on different aneurysm models varying size and aspect ratio. The effect of geometry factors on hemdyanmics was analyzed. By considering the causative factors to the rupture of aneursms such as drinking, exciting etc, numerical simulations with a sudden changed inlet velocity waveform were conducterd to consider the influence of those factors. The hemodynamics of cerebral aneurysm before and after the flow rate changed was compared to analyze the hemodynamical factors which may lead to the rupture of aneurysm.In the second part, a patient-specific lateral aneruysm and terminal aneurysm was generated from MRI/CT data using 3D reconstruction method. Hemodynamics was investigated by conducting CFD simulation. The role of the hemodynamical factors such as WSS, velocity, OSI etc. in the process of the rupture of aneurysm was discussed through comparasion analysis. In the last part, by combining CFD and FEA, the fluid-structure interaction (FSI) modeling was conducted on an ACoA aneurysm with one A1 segment absence which is special for its high incidence rate. By comparing the results of the rigid model and the compliant model of this ACoA aneurysm, the effect of the compliant wall was presented.The hemodyanamics in intracranial aneurysm was systematical studied in this research, which may provide helpful information for the related clinical researches. The mothed to combine CFD, MRI/CT, 3D reconstruction and FSI techniques provides a successful platform in similar researches to help solving other medical problems.