Computational fluid dynamic simulation of human carotid artery bifurcation based on anatomy and volumetric blood flow rate measured with magnetic resonance imaging.
Computational fluid dynamic simulation of human carotid artery bifurcation based on anatomy and volumetric blood flow rate measured with magnetic resonance imaging.
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DOI：
10.1007/s12572-016-0161-6
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发表时间：
2016-03
影响因子：
0.9
通讯作者：
Baek S
中科院分区：
文献类型：
--
作者：
Gharahi H;Zambrano BA;Zhu DC;DeMarco JK;Baek S
血流模式和局部血流动力学参数与颈动脉粥样硬化的发生和进展广泛相关。这些参数的评估可以使用电影相位对比（PC）磁共振成像（MRI）进行非侵入性。此外，在过去的二十年中，计算流体动力学（CFD）模拟的三维模型，从解剖医学图像已被用来研究颈动脉中的血流。这项研究开发了一个工作流程的主题特定的CFD分析使用MRI，以提高估计颈动脉的血流动力学。飞行时间（TOF）MRI扫描用于构建三维计算模型。利用PC-MRI测量在入口处施加边界条件，并采用0维集总参数模型作为流出边界条件。选择不同的粘度模型的血流作为一个来源的不确定性进行了研究，通过轴向速度，壁面剪切应力，和振荡剪切指数。使用PC-MRI针对健康受试者优化了CFD分析中的工作流程顺序。然后，一个病人的颈动脉狭窄及其血流动力学参数进行了检查。仿真结果表明，在出口处使用的集总参数模型给出了生理上合理的血流动力学参数值。此外，血液动力学参数对粘度模型的依赖性被观察到不同的几何形状。然而，为了进行更准确的CFD分析，可能需要其他因素，例如几何模型的分割和平滑度、动脉壁的机械特性以及入口处的规定速度分布。
Blood flow patterns and local hemodynamic parameters have been widely associated with the onset and progression of atherosclerosis in the carotid artery. Assessment of these parameters can be performed noninvasively using cine phase-contrast (PC) magnetic resonance imaging (MRI). In addition, in the last two decades, computational fluid dynamics (CFD) simulation in three dimensional models derived from anatomic medical images has been employed to investigate the blood flow in the carotid artery. This study developed a workflow of a subject-specific CFD analysis using MRI to enhance estimating hemodynamics of the carotid artery. Time-of-flight (TOF) MRI scans were used to construct three-dimensional computational models. PC-MRI measurements were utilized to impose the boundary condition at the inlet and a 0-dimensional lumped parameter model was employed for the outflow boundary condition. The choice of different viscosity models of blood flow as a source of uncertainty was studied, by means of the axial velocity, wall shear stress, and oscillatory shear index. The sequence of workflow in CFD analysis was optimized for a healthy subject using PC-MRI. Then, a patient with carotid artery stenosis and its hemodynamic parameters were examined. The simulations indicated that the lumped parameter model used at the outlet gives physiologically reasonable values of hemodynamic parameters. Moreover, the dependence of hemodynamics parameters on the viscosity models was observed to vary for different geometries. Other factors, however, may be required for a more accurate CFD analysis, such as the segmentation and smoothness of the geometrical model, mechanical properties of the artery’s wall, and the prescribed velocity profile at the inlet.