High angular resolution diffusion imaging reveals intravoxel white matter fiber heterogeneity
High angular resolution diffusion imaging reveals intravoxel white matter fiber heterogeneity
复制标题
DOI：
10.1002/mrm.10268
复制
发表时间：
2002-10-01
影响因子：
3.3
通讯作者：
Wedeen, VJ
中科院分区：
文献类型：
--
作者：
Tuch, DS;Reese, TG;Wedeen, VJ
磁共振（MR）扩散张量成像（DTI）可以解决的白色纤维取向的体素内的纤维提供了强烈的对齐。然而，给定的体素可以包含由于例如体素内纤维交叉而导致的纤维取向的分布。本研究旨在测试测地线，高b值扩散梯度采样方案是否可以解决多个纤维方向在一个单一的体素。在纤维交叉的区域中，扩散信号表现出多个局部最大值/最小值作为扩散梯度方向的函数，表明存在多个体素内纤维方向。所观察到的扩散信号的多模态排除了标准张量重建，因此取而代之的是，扩散信号被建模为从缓慢交换中的高斯扩散过程的离散混合物中产生，并且使用梯度下降方案来求解张量的基础混合物。多张量重建解析了与已知纤维解剖结构相对应的多个体素内纤维群。(C)2002 Wiley-Liss，Inc.
Magnetic resonance (MR) diffusion tensor imaging (DTI) can resolve the white matter fiber orientation within a voxel provided that the fibers are strongly aligned. However, a given voxel may contain a distribution of fiber orientations due to, for example, intravoxel fiber crossing. The present study sought to test whether a geodesic, high b-value diffusion gradient sampling scheme could resolve multiple fiber orientations within a single voxel. In regions of fiber crossing the diffusion signal exhibited multiple local maxima/minima as a function of diffusion gradient orientation, indicating the presence of multiple intravoxel fiber orientations. The multimodality of the observed diffusion signal precluded the standard tensor reconstruction, so instead the diffusion signal was modeled as arising from a discrete mixture of Gaussian diffusion processes in slow exchange, and the underlying mixture of tensors was solved for using a gradient descent scheme. The multitensor reconstruction resolved multiple intravoxel fiber populations corresponding to known fiber anatomy. (C) 2002 Wiley-Liss, Inc.