Steinman D A, Frayne R, Zhang X D, Rutt B K, Ethier C R
Department of Diagnostic Radiology, University of Western Ontario, London, Canada.
J Biomech. 1996 Apr;29(4):537-42. doi: 10.1016/0021-9290(95)00080-1.
Magnetic resonance phase contrast velocity imaging ('MR PC velocimetry') is a powerful tool for measuring blood velocity. While it has been demonstrated that MR PC velocimetry can accurately measure velocity profiles in simple, unidirectional flows, errors can arise when measuring the more complex, multidirectional flows of clinical importance. In this work, we have compared MR PC velocity measurements with numerical simulations of steady flow in a physiologically relevant model of an end-to-side anastomosis, which produces many of the complex flow features expected in vivo. MR PC velocity profiles, measured using both 2D and 3D pulse sequences, showed very good agreement with numerically computed profiles, although at 2D PC data showed slightly larger errors than the 3D PC data in regions of high accelerations and oblique flow, likely due to displacement artifacts. We conclude that, under ideal conditions, MR phase contrast velocimetry can measure complex flow patterns to within 15% accuracy, but that care should be taken when using 2D pulse sequences to measure such complex flows.
磁共振相位对比速度成像（“MR PC测速法”）是测量血流速度的强大工具。虽然已证明MR PC测速法能够准确测量简单单向血流中的速度分布，但在测量具有临床重要性的更复杂多向血流时可能会出现误差。在这项工作中，我们将MR PC速度测量结果与端侧吻合生理相关模型中稳定血流的数值模拟进行了比较，该模型会产生许多体内预期的复杂血流特征。使用二维和三维脉冲序列测量的MR PC速度分布与数值计算的分布显示出非常好的一致性，尽管在二维PC数据中，在高加速度和斜向血流区域显示出比三维PC数据稍大的误差，这可能是由于位移伪影所致。我们得出结论，在理想条件下，MR相位对比测速法能够测量复杂血流模式，精度可达15%以内，但在使用二维脉冲序列测量此类复杂血流时应谨慎。
