Department of Radiology, G1-230, Academic Medical Center, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.
Department of Radiology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.
MAGMA. 2015 Oct;28(5):427-36. doi: 10.1007/s10334-014-0480-1. Epub 2015 Jan 15.
The current study assesses the multicenter feasibility of pharmacological arterial spin labeling (ASL) by comparing a caffeine-induced relative cerebral blood flow decrease (%CBF↓) measured with two pseudo-continuous ASL sequences as provided by two major vendors.
Twenty-two healthy volunteers were scanned twice with both a 3D spiral (GE) and a 2D EPI (Philips) sequence. The inter-session reproducibility was evaluated by comparisons of the mean and within-subject coefficient of variability (wsCV) of the %CBF↓, both for the total cerebral gray matter and on a voxel level.
The %CBF↓ was larger when measured with the 3D spiral sequence (23.9 ± 5.9 %) than when measured with the 2D EPI sequence (19.2 ± 5.6 %) on a total gray matter level (p = 0.02), and on a voxel level in the posterior watershed area (p < 0.001). There was no difference between the gray matter wsCV of the 3D spiral (57.3 %) and 2D EPI sequence (66.7 %, p = 0.3), whereas on a voxel level, the wsCV was visibly different between the sequences.
The observed differences between ASL sequences of both vendors can be explained by differences in the employed readout modules. These differences may seriously hamper multicenter pharmacological ASL, which strongly encourages standardization of ASL implementations.
本研究通过比较两种主要供应商提供的两种伪连续动脉自旋标记（ASL）序列测量的咖啡因诱导的相对脑血流减少（%CBF↓），评估药理学 ASL 的多中心可行性。
22 名健康志愿者分别使用 3D 螺旋（GE）和 2D EPI（Philips）序列进行两次扫描。通过比较 %CBF↓的平均值和个体内变异系数（wsCV），评估两次扫描之间的可重复性，分别对全脑灰质和体素水平进行评估。
在全脑灰质水平上，3D 螺旋序列（23.9±5.9%）测量的 %CBF↓大于 2D EPI 序列（19.2±5.6%）（p=0.02），在后分水岭区域的体素水平上也存在显著差异（p<0.001）。3D 螺旋序列（57.3%）和 2D EPI 序列的灰质 wsCV 之间无差异（p=0.3），而在体素水平上，两种序列的 wsCV 存在明显差异。
两种供应商的 ASL 序列之间的差异可以用所使用的读出模块的差异来解释。这些差异可能严重阻碍多中心药理学 ASL，强烈鼓励 ASL 实施的标准化。
