Accurate myocardial T1 measurements:: Toward quantification of myocardial blood flow with arterial spin labeling
Accurate myocardial T1 measurements:: Toward quantification of myocardial blood flow with arterial spin labeling
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DOI：
10.1002/mrm.20461
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发表时间：
2005-05-01
影响因子：
3.3
通讯作者：
Zheng, J
中科院分区：
文献类型：
--
作者：
Zhang, HS;Shea, SM;Zheng, J
在这项研究中，我们研究了一种精确测量心肌T-1的方法，用于动脉自旋标记（ASL）定量心肌血流量（MBF）。采用绝热双曲正割反转恢复脉冲对单次梯度回波（GE） ASL序列进行修改，以获得屏气时的一对心肌T-1。提出了一种考虑磁化饱和效应的多变量回归算法来计算T-1。然后用一个完善的模型来确定MBF。我们首先在一只假体中评估T-1计算的准确性，然后在6只狗中进行MBF计算，其中有（N = 4）和没有（N = 2）冠状动脉狭窄。在幻像研究中，用切片选择性反转制备的脉冲测量T的准确度在误差的2.5%以内。在健康犬中，MBF在血管舒张期间增加2-5倍。相比之下，狭窄犬在血管舒张期间MBF的区域差异很明显（正常心肌灌注储备为2.75 +/- 0.83，狭窄区为1.46 +/- 0.75）。相关分析显示，在健康和狭窄犬的ASL和微球（MS）之间的MBF密切一致。总之，本文提出的改进ASL技术和T-1回归算法提供了心肌T-1的精确测量，并证明了稳定状态下可靠评估MBF的潜力。中华医学杂志，2005,31(3):535 - 542。(c) 2005 Wiley-Liss, Inc。
In this study, we investigated a method for accurately measuring myocardial T-1 for the quantification of myocardial blood flow (MBF) with arterial spin labeling (ASL). A single-shot gradient-echo (GE)-based ASL sequence with an adiabatic hyperbolic secant inversion recovery pulse was modified to acquire a pair of myocardial T-1's within a breath-hold. A multivariable regression algorithm that accounted for the magnetization saturation effects was developed to calculate T-1. The MBF was then determined with a well-developed model. The accuracy of our T-1 calculation was first evaluated in a phantom, and then in six dogs for the MBF calculation, with (N = 4) and without (N = 2) coronary artery stenosis. In the phantom study, the accuracy of T, measured with a slice-selective inversion prepared pulse was within 2.5% of error. In healthy dogs, the MBF increased 2-5 times during vasodilation. In contrast, regional differences of MBF were well visualized in the stenotic dogs during vasodilation (perfusion reserve of 2.75 +/- 0.83 in normal myocardium, and 1.46 +/- 0.75 in the stenotic area). A correlation analysis revealed a close agreement in MBF between the ASL and microsphere (MS) in both healthy and stenotic dogs. In summary, the modified ASL technique and T-1 regression algorithm proposed here provide an accurate measurement of myocardial T-1 and demonstrate potential for reliably assessing MBF at steady state. Magn Reson Med 53:1135-1142, 2005. (c) 2005 Wiley-Liss, Inc.