Bouwman C J C, Wilmink J T, Mess W H, Backes W H
Department of Radiology, Medical University Center Maastricht (MUCM+), The Netherlands.
Neuroimage. 2008 Nov 1;43(2):288-96. doi: 10.1016/j.neuroimage.2008.07.024. Epub 2008 Jul 23.
The purpose of this study was to evaluate and compare turbo spin echo (TSE) with gradient echo echo-planar imaging (GE-EPI) pulse sequences for functional magnetic resonance imaging (fMRI) of spinal cord activation at 3 T field strength. Healthy volunteers underwent TSE and GE-EPI spinal fMRI. The activation paradigm comprised the temporal alternation of finger motion and rest. Pulse sequences were optimized to obtain sufficient image quality and optimal sensitivity to small T(2) or T(2)* relaxation time changes. Spinal cord activation measured by the two pulse sequences was evaluated with respect to spatial distribution of activation, signal sensitivity, and reproducibility. For the GE-EPI sequence, fMRI activation was maximal in the spinal cord segments at the levels of the fifth cervical down to the first thoracic vertebra. For the TSE sequence, fMRI measurements showed no distinct location with maximal activation. Percentage signal change and number of activated voxels were approximately twice as high for GE-EPI compared to TSE fMRI. Reproducibility of the signal changes was much better for GE-EPI than for TSE imaging. To conclude, multi-subjects averaged GE-EPI is more location specific for blood-oxygen-level-dependent (BOLD) activation, more sensitive, and is suggested to be more reproducible than TSE fMRI.
本研究的目的是在3T场强下，评估和比较用于脊髓激活功能磁共振成像（fMRI）的涡轮自旋回波（TSE）与梯度回波平面成像（GE-EPI）脉冲序列。健康志愿者接受了TSE和GE-EPI脊髓fMRI检查。激活范式包括手指运动和休息的时间交替。对脉冲序列进行了优化，以获得足够的图像质量和对小T(2)或T(2)*弛豫时间变化的最佳敏感性。通过两个脉冲序列测量的脊髓激活在激活的空间分布、信号敏感性和可重复性方面进行了评估。对于GE-EPI序列，fMRI激活在第五颈椎至第一胸椎水平的脊髓节段中最大。对于TSE序列，fMRI测量未显示出激活最大的明显位置。与TSE fMRI相比，GE-EPI的信号变化百分比和激活体素数量大约高出两倍。GE-EPI的信号变化可重复性比TSE成像要好得多。总之，多受试者平均GE-EPI对于血氧水平依赖（BOLD）激活更具位置特异性，更敏感，并且比TSE fMRI更具可重复性。
