Individualized Hemodynamics Model And Experimental Verification Of The Intracranial Aneurysms Based On Computational Fluid Dynamics Technique

OBJECTIVE:To establish the individualized rigid model and fluid-solid coupled model of intracranial aneurysms based on Computational Fluid Dynamics technique,verify the model,analyse the reliability of the model,and investigate the mechanism of the growth and rupture of intracranial aneurysms.METHODS: The original Dicom format image data from a patient with a intracranial aneurysm were imported by the Mimics software directly,the 3D object was constructed. The simulation of rigid model was made with CFX software,the hemodynamics parameters related to the growth and rupture of aneurysms were analysed.The simulation of fluid-solid coupled model was made with ANSYS and CFX softwares,the hemodynamics parameters related to the growth and rupture of aneurysms were analysed,and the difference between the rigid model and fluid-solid coupled model was compared.The intraoperative Microvascular Doppler Ultrasonography was conducted to examine the blood flow velocity of the aneurysm which was compared with data from the simulation of the aneurysm.RESULTS:The accurate rigid model and fluid-solid coupled model of the intracranial aneurysm were established successfully,which can simulate the blood flow of the intracranial aneurysm and the deformation of the solid wall directly. The pressure field,stress field,distribution of von mises stress and deformation of the aneurysm could be exported with this technigue.Compared with the rigid model,the simulation of fluid-solid coupled model was more accurate.The wall shear stress on the tip of aneurysms was extremely low,however the stress on the neck impinged by the blood flow was the highest compared with the other sites of the aneurysm.The yon mises stress of the neck was higher than that of tip,but the distribution of von mises stress and the deformation of the tip were more complex. The consistency was found in the velocity result between the simulation and the Intraoperative Microvascular Doppler Ultrasonography.CONCLUSION:The method of the rigid model and fluid-solid coupled model of the intracranial aneurysm are fast and accurate.The simulation of the fluid-solid coupled model is more accurate than the rigid model.The hemodynamics parameters such as wall shear stress are involved in the origin,growth and rupture of intracranial aneurysms,and the von mises stress and the deformation of wall might be critical to the rupture of intracranial aneurysms.The results of the numerical simulation of the model are reliable to the diagnosis and treatment of the aneurysms,and could be an ideal method in the prediction of intracranial aneurysms in the future.