Model-free arterial spin labeling quantification approach for perfusion MRI
Model-free arterial spin labeling quantification approach for perfusion MRI
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DOI：
10.1002/mrm.20784
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发表时间：
2006-02-01
影响因子：
3.3
通讯作者：
Golay, X
中科院分区：
文献类型：
--
作者：
Petersen, ET;Lim, T;Golay, X
本文提出了一种无模型动脉自旋标记（ASL）定量测量脑血流量（CBF）和动脉血容量（aBV）的方法。该方法是基于在标记方案下获取多幅图像的训练。灌注是通过反褶积获得的，其方式类似于动态敏感性对比（DSG） MRI。局部动脉输入函数（aif）可以通过分别减去有和没有破碎梯度获得的两张灌注加权图像来估计。此外，通过知道标记动脉血块的持续时间，可以在逐体素的基础上估计aBV。由AIF对组织曲线进行反褶积得到的残差函数的最大值是由局部估计的aBV缩放后的CBF的度量。该方法提供的灰质（GM）平均灌注值为38 +/- 2 ml/min/100 g， aBV为0.93% +/- 0.06%。平均CBF值比使用标准通用动力学模型（42.2 ml/min/100 g）在相同数据集上获得的CBF值小10%。通过蒙特卡罗模拟，将该方法与传统模型的参数拟合方法进行了比较。
In this work a model-free arterial spin labeling (ASL) quantification approach for measuring cerebral blood flow (CBF) and arterial blood volume (aBV) is proposed. The method is based on the acquisition of a train of multiple images following the labeling scheme. Perfusion is obtained using deconvolution in a manner similar to that of dynamic susceptibility contrast (DSG) MRI. Local arterial input functions (AIFs) can be estimated by subtracting two perfusion-weighted images acquired with and without crusher gradients, respectively. Furthermore, by knowing the duration of the bolus of tagged arterial blood, one can estimate the aBV on a voxel-by-voxel basis. The maximum of the residue function obtained from the deconvolution of the tissue curve by the AIF is a measure of CBF after scaling by the locally estimated aBV. This method provides averaged gray matter (GM) perfusion values of 38 +/- 2 ml/min/100 g and aBV of 0.93% +/- 0.06%. The average CBF value is 10% smaller than that obtained on the same data set using the standard general kinetic model (42 2 ml/min/100 g). Monte Carlo simulations were performed to compare this new methodology with parametric fitting by the conventional model.