Duong Timothy Q, Yacoub Essa, Adriany Gregory, Hu Xiaoping, Ugurbil Kamil, Vaughan J Thomas, Merkle Hellmut, Kim Seong-Gi
Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota School of Medicine, Minneapolis, USA.
Magn Reson Med. 2002 Oct;48(4):589-93. doi: 10.1002/mrm.10252.
With growing interest in noninvasive mapping of columnar organization and other small functional structures in the brain, achieving high spatial resolution and specificity in fMRI is of critical importance. We implemented a simple method for BOLD and perfusion fMRI with high spatial resolution and specificity. Increased spatial resolution was achieved by selectively exciting a slab of interest along the phase-encoding direction for EPI, resulting in a reduced FOV and number of phase-encoding steps. Improved spatial specificity was achieved by using SE EPI acquisition at high fields, where it is predominantly sensitive to signal changes in the microvasculature. Robust SE BOLD and perfusion fMRI were obtained with a nominal in-plane resolution up to 0.5 x 0.5 mm(2) at 7 and 4 Tesla, and were highly reproducible under repeated measures. This methodology enables high-resolution and high-specificity studies of functional topography in the millimeter to submillimeter spatial scales of the human brain.
随着人们对大脑柱状组织及其他小功能结构的无创映射兴趣日增，在功能磁共振成像（fMRI）中实现高空间分辨率和特异性至关重要。我们实施了一种用于血氧水平依赖性功能磁共振成像（BOLD-fMRI）和灌注功能磁共振成像的简单方法，该方法具有高空间分辨率和特异性。通过沿回波平面成像（EPI）的相位编码方向选择性激发感兴趣的层面，提高了空间分辨率，从而减小了视野（FOV）并减少了相位编码步数。通过在高场强下使用自旋回波（SE）EPI采集来提高空间特异性，在高场强下它主要对微脉管系统中的信号变化敏感。在7特斯拉和4特斯拉场强下获得了稳健的SE BOLD和灌注功能磁共振成像，标称平面分辨率高达0.5×0.5毫米²，并且在重复测量下具有高度可重复性。这种方法能够在人脑的毫米至亚毫米空间尺度上对功能地形图进行高分辨率和高特异性研究。
