Validation of the Reduced Unified Continuum Formulation Against In Vitro 4D-Flow MRI
Validation of the Reduced Unified Continuum Formulation Against In Vitro 4D-Flow MRI
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DOI：
10.1007/s10439-022-03038-4
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发表时间：
2022-08-13
影响因子：
3.8
通讯作者：
Marsden, Alison L.
中科院分区：
文献类型：
--
作者：
Lan, Ingrid S.;Liu, Ju;Marsden, Alison L.
我们以前引入并验证了血管流固相互作用的简化统一连续统公式，该公式与沃姆斯利的可变形壁理论相反。我们目前的工作试图调查它在患者特定的主动脉环境中的性能，其中理想化的几何和速度曲线的假设是无效的。具体地说，我们利用2D磁共振成像(MRI)和4D-Flow MRI从嵌入顺应性3D打印的主动脉模型的体外血流回路中提取高分辨率的解剖和血流动力学信息。为了准确地反映实验条件，我们在数值上实现了粘弹性外部组织支撑、血管组织预应力和倾斜边界条件，使得每个入口和出口处的血管能够在平面内运动。我们公式的验证是通过在压力、管腔面积变化、脉搏波速度和收缩早期速度方面的密切定量一致，以及在收缩晚期血流结构的定性一致来实现的。我们经过验证的FSI技术套件为血管血流动力学的数值模拟提供了一种计算高效的方法。这项研究是首次验证心血管FSI配方与涉及复杂患者特定解剖的顺应性血管体模的体外流动回路的对比。
We previously introduced and verified the reduced unified continuum formulation for vascular fluid-structure interaction (FSI) against Womersley's deformable wall theory. Our present work seeks to investigate its performance in a patient-specific aortic setting in which assumptions of idealized geometries and velocity profiles are invalid. Specifically, we leveraged 2D magnetic resonance imaging (MRI) and 4D-flow MRI to extract high-resolution anatomical and hemodynamic information from an in vitro flow circuit embedding a compliant 3D-printed aortic phantom. To accurately reflect experimental conditions, we numerically implemented viscoelastic external tissue support, vascular tissue prestressing, and skew boundary conditions enabling in-plane vascular motion at each inlet and outlet. Validation of our formulation is achieved through close quantitative agreement in pressures, lumen area changes, pulse wave velocity, and early systolic velocities, as well as qualitative agreement in late systolic flow structures. Our validated suite of FSI techniques offers a computationally efficient approach for numerical simulation of vascular hemodynamics. This study is among the first to validate a cardiovascular FSI formulation against an in vitro flow circuit involving a compliant vascular phantom of complex patient-specific anatomy.