Department of Engineering Science, University of Oxford, Parks Road, Oxford OX1 3PJ, UK.
Phys Med Biol. 2010 Feb 7;55(3):799-816. doi: 10.1088/0031-9155/55/3/017. Epub 2010 Jan 14.
It has recently been demonstrated experimentally that cardiac pulsations seem significantly to affect the arterial spin labelling (ASL) signal. In this paper, we introduce a new theoretical model to examine this effect. Existing models of ASL do not take such effects into account since they model the transit of the ASL signal assuming uniform plug flow with a single transit delay. In this study, we model cardiac pulsations through the coupling of the Navier-Stokes equations with the three-dimensional mass transport equation. Our results complement the experimental findings and suggest that the ASL signal does depend on the timing of the onset of the cardiac cycle relative to the tagging and imaging locations. However, cardiac pulsatility only appears to have a small effect on the quantification of perfusion estimates.
最近的实验研究表明，心脏搏动对动脉自旋标记（ASL）信号有显著影响。本文引入了一种新的理论模型来研究这种效应。现有的 ASL 模型没有考虑到这种影响，因为它们假设 ASL 信号的传输是均匀的塞流，只有一个传输延迟。在这项研究中，我们通过将纳维-斯托克斯方程与三维质量传输方程耦合来模拟心脏搏动。我们的研究结果补充了实验发现，并表明 ASL 信号确实取决于心脏周期相对于标记和成像位置的起始时间。然而，心脏搏动似乎对灌注估计的定量影响很小。
