Mapping brain function using a 30-day interval between baseline and activation: a novel arterial spin labeling fMRI approach
Mapping brain function using a 30-day interval between baseline and activation: a novel arterial spin labeling fMRI approach
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DOI：
10.1038/jcbfm.2010.89
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发表时间：
2010-10-01
影响因子：
6.3
通讯作者：
Asllani, Iris
中科院分区：
文献类型：
--
作者：
Borogovac, Ajna;Habeck, Christian;Asllani, Iris
通过比较激活前即刻和激活期间采集的血流动力学信号，功能性磁共振成像（fMRI）非常适合绘制脑功能的急性变化。然而，目前还不清楚功能磁共振成像是否可以在更长的时间内映射功能变化。在这里，我们解决这个问题的可行性动脉自旋标记（ASL）功能磁共振成像检测脑血流量（CBF）的基线和任务分开1个月的变化进行了实证测试。为了增加该方法的灵敏度，我们应用了一种算法，该算法产生的血流密度（CBFd）图像与组织内容无关。为了提高准确性，我们开发了一种在每个体素独立生成动脉通过时间的技术。结果显示，在同一时间段内CBFd的激活变化与30天内的变化在统计学上相同。第30天的活化CBFd比第1天获得的83和107 mL/100 g/min的相应基线高34%（运动）和25%（视觉）。此外，CBFd测量的信噪比分别是受试者内和受试者间比较的传统CBF的2.1倍和2.9倍（n = 9名健康年轻受试者）。总之，这些结果表明，CBFd测量可能比净CBF更适合于绘制脑功能的长期变化。Journal of Cerebral Blood Flow & Metabolism（2010）30，1721-1733; doi：10.1038/jcbfm.2010.89; 2010年7月21日在线发表
By comparing hemodynamic signals acquired immediately before and during activation, functional magnetic resonance imaging (fMRI) is well suited for mapping acute changes in brain function. However, it remains unclear whether fMRI can map functional changes over longer periods. Here, we address this issue by empirically testing the feasibility of arterial spin labeling (ASL) fMRI to detect changes in cerebral blood flow (CBF) with baseline and task separated by 1 month. To increase the sensitivity of the method, we applied an algorithm that yielded flow density (CBFd) images that were independent of tissue content. To increase the accuracy, we developed a technique that generated arterial transit time at each voxel, independently. Results showed that activation changes in CBFd during the same session were statistically the same as across 30 days. The activation CBFd on day-30 was 34% (motor) and 25% (visual) higher than the respective baselines of 83 and 107 mL/100 g/min obtained on day-1. Furthermore, the signal-to-noise ratio of the CBFd measurement was 2.1 and 2.9 times higher than that of the conventional CBF for within-subject and across-subjects comparisons, respectively (n = 9 healthy young subjects). Taken together, these results indicate that CBFd measure could be better suited than net CBF to map long-term changes in brain function. Journal of Cerebral Blood Flow & Metabolism (2010) 30, 1721-1733; doi:10.1038/jcbfm.2010.89; published online 21 July 2010