Inflow boundary conditions for image-based computational hemodynamics: Impact of idealized versus measured velocity profiles in the human aorta
Inflow boundary conditions for image-based computational hemodynamics: Impact of idealized versus measured velocity profiles in the human aorta
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DOI：
10.1016/j.jbiomech.2012.10.012
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发表时间：
2013-01-04
影响因子：
2.4
通讯作者：
Rizzo, Giovanna
中科院分区：
文献类型：
--
作者：
Morbiducci, Umberto;Ponzini, Raffaele;Rizzo, Giovanna
在这里，我们分析的假设的影响，从相位对比磁共振成像（PC-MRI）在体内测得的流量数据提取的边界条件（BCs），应用于人体主动脉的血液动力学模型。本研究旨在调查基于有缺陷的信息（即使是测量和特定于受试者的信息）实施BC是否可能导致误导性的主动脉血流动力学数值表示。详细地说，我们专注于假设的影响，在升主动脉的入口部分的速度分布，将相流数据内的计算模型。所获得的结果进行了比较，在扰动剪切和螺旋体流结构，当相同的测量流量规定为进口BC的三维或一维（轴向）测量或理想化的速度分布。我们的研究结果清楚地表明：（1）施加PC-MRI测量的轴向速度剖面作为流入BC可以足够准确地捕获扰动剪切，而无需规定（和测量）真实的全三维速度剖面;（2）在研究主动脉整体流动特性时，应注意在主动脉计算模型的入口边界处设置理想化或PC-MRI测量的轴向速度分布，因为螺旋流结构明显受到流入端规定的BC的影响。我们得出结论，在个性化计算模型中，将理想化速度剖面假设为入口BC的假设的可接受性可能导致在扰动剪切和整体流结构方面对主动脉血流动力学的误导性表示。(C)2012爱思唯尔有限公司保留所有权利。
Here we analyse the influence of assumptions made on boundary conditions (BCs) extracted from phase-contrast magnetic resonance imaging (PC-MRI) in vivo measured flow data, applied on hemodynamic models of human aorta. This study aims at investigating if the imposition of BCs based on defective information, even when measured and specific-to-the-subject, might lead to misleading numerical representations of the aortic hemodynamics. In detail, we focus on the influence of assumptions regarding velocity profiles at the inlet section of the ascending aorta, incorporating phase flow data within the computational model. The obtained results are compared in terms of disturbed shear and helical bulk flow structures, when the same measured flow rate is prescribed as inlet BC in terms of 3D or 1D (axial) measured or idealized velocity profiles. Our findings clearly indicate that: (1) the imposition of PC-MRI measured axial velocity profiles as inflow BC may capture disturbed shear with sufficient accuracy, without the need to prescribe (and measure) realistic fully 3D velocity profiles; (2) attention should be put in setting idealized or PC-MRI measured axial velocity profiles at the inlet boundaries of aortic computational models when bulk flow features are investigated, because helical flow structures are markedly affected by the BC prescribed at the inflow.We conclude that the plausibility of the assumption of idealized velocity profiles as inlet BCs in personalized computational models can lead to misleading representations of the aortic hemodynamics both in terms of disturbed shear and bulk flow structures. (C) 2012 Elsevier Ltd. All rights reserved.