Observation of microscopic diffusion anisotropy in the spinal cord using double-pulsed gradient spin echo MRI
Observation of microscopic diffusion anisotropy in the spinal cord using double-pulsed gradient spin echo MRI
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DOI：
10.1002/mrm.21528
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发表时间：
2008-04-01
影响因子：
3.3
通讯作者：
Basser, P. J.
中科院分区：
文献类型：
--
作者：
Komlosh, M. E.;Lizak, M. J.;Basser, P. J.
提出了一种双脉冲梯度自旋回波（d-PGSE）滤波MRI序列来检测非均匀样品中的微观扩散各向异性。该技术的发展，特别是，表征局部微观各向异性的标本，宏观各向同性，如灰质。在这样的样本中，扩散张量MRI（DTI）产生各向同性或接近各向同性的扩散张量，尽管介质在微观长度尺度上可能是各向异性的。使用d-PGSE过滤MRI，在由随机取向的充满水的管组成的“灰质”体模中以及在固定的猪脊髓中观察到显微各向异性，在临床和小动物MR扫描仪上容易实现的b值范围内。这些发现表明，这种新的对比机制在临床研究和生物学研究应用中具有潜在的用途。
A double-pulsed gradient spin echo (d-PGSE) filtered MRI sequence is proposed to detect microscopic diffusion anisotropy in heterogeneous specimen. The technique was developed, in particular, to characterize local microscopic anisotropy in specimens that are macroscopically isotropic, such as gray matter. In such samples, diffusion tensor MRI (DTI) produces an isotropic or nearly isotropic diffusion tensor despite the fact that the medium may be anisotropic at a microscopic length scale. Using d-PGSE filtered MRI, microscopic anisotropy was observed in a "gray matter" phantom consisting of randomly oriented tubes filled with water, as well as in fixed pig spinal cord, within a range of b-values that can be readily achieved on clinical and small animal MR scanners. These findings suggest a potential use for this new contrast mechanism in clinical studies and biological research applications.