4D Flow MRI-Based Pressure Loss Estimation in Stenotic Flows: Evaluation Using Numerical Simulations
4D Flow MRI-Based Pressure Loss Estimation in Stenotic Flows: Evaluation Using Numerical Simulations
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DOI：
10.1002/mrm.25772
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发表时间：
2016-04-01
影响因子：
3.3
通讯作者：
Ebbers, Tino
中科院分区：
文献类型：
--
作者：
Casas, Belen;Lantz, Jonas;Ebbers, Tino
目的：为了评估如何4D流MRI为基础的压力和能量损失估计对应于净transstenotic压力梯度（TPG（净））和空间resolution.Methods的依赖性：狭窄流的数值速度数据从计算流体动力学（CFD）模拟几何形状不同的狭窄程度，poststenotic直径和流速。在不同的空间分辨率下模拟MRI测量。结果：简化的Bernoulli方程高估了真实的TPG（net）（8.74 ± 0.67 vs 6.76 ± 0.54 mmHg）;扩展的伯努利方程表现更好（6.57 +/- 0.53 mmHg），尽管误差仍保持在低TPG（净）。使用财产、厂房和设备得出的总产值（净）估计数总是接近于零。总TKE和粘性耗散与每种几何形状的TPG（净）强相关（r（2）> 0.93），考虑到所有几何形状（分别为r（2）= 0.756和r（2）= 0.776），则与TPG（净）中度相关。TKE估计值准确，受分辨率影响较小。粘性耗散整体低估和resolution dependent.Conclusion：几个参数高估或不线性相关的TPG（净）和/或依赖于空间分辨率。考虑到理想轴对称几何形状，在没有噪声的情况下，TPG（net）的最佳估计使用扩展的伯努利方程。(C)2015作者《医学中的磁共振》（Magnetic Resonance in Medicine），Wiley Periodicals，Inc.出版。代表国际磁共振学会
Purpose: To assess how 4D flow MRI-based pressure and energy loss estimates correspond to net transstenotic pressure gradients (TPG(net)) and their dependence on spatial resolution.Methods: Numerical velocity data of stenotic flow were obtained from computational fluid dynamics (CFD) simulations in geometries with varying stenosis degrees, poststenotic diameters and flow rates. MRI measurements were simulated at different spatial resolutions. The simplified and extended Bernoulli equations, Pressure-Poisson equation (PPE), and integration of turbulent kinetic energy (TKE) and viscous dissipation were compared against the true TPG(net).Results: The simplified Bernoulli equation overestimated the true TPG(net) (8.74 +/- 0.67 versus 6.76 +/- 0.54 mmHg). The extended Bernoulli equation performed better (6.57 +/- 0.53 mmHg), although errors remained at low TPG(net). TPG(net) estimations using the PPE were always close to zero. Total TKE and viscous dissipation correlated strongly with TPG(net) for each geometry (r(2) > 0.93) and moderately considering all geometries (r(2) = 0.756 and r(2) = 0.776, respectively). TKE estimates were accurate and minorly impacted by resolution. Viscous dissipation was overall underestimated and resolution dependent.Conclusion: Several parameters overestimate or are not linearly related to TPG(net) and/or depend on spatial resolution. Considering idealized axisymmetric geometries and in absence of noise, TPG(net) was best estimated using the extended Bernoulli equation. (C) 2015 The Authors. Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance.