Microstructural and physiological features of tissues elucidated by quantitative-diffusion-tensor MRI
Microstructural and physiological features of tissues elucidated by quantitative-diffusion-tensor MRI
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DOI：
10.1016/j.jmr.2011.09.022
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发表时间：
1996-06-01
期刊：
影响因子：
--
通讯作者：
Pierpaoli, C
中科院分区：
文献类型：
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作者：
Basser, PJ;Pierpaoli, C
定量扩散张量MRI包括导出和显示类似于组织学或生理学染色的参数，即，表征组织微观结构和微观动力学的内在特征。具体地说，这些参数是客观的，并且对实验室坐标系的选择不敏感。在这里，这两个属性用于导出扩散各向同性的体素内测量和扩散各向异性的程度，以及结构相似性的体素间测量，以及来自在每个体素中估计的有效扩散张量（D）下的纤维束组织。首先，将（D）under bar分解为各向同性和各向异性部分，分别为[D]（I）under bar和（D）under bar - [D]（I）under bar（其中[D] = Trace（（D）under bar）/3为平均扩散率，（I）under bar为单位张量）。然后，张量（点）积算子被用来生成一个家庭的新的旋转和旋转不变量。最后，这些定量参数的地图，从高分辨率的扩散张量图像（其中（D）下的酒吧估计在每个体素从一系列的2D-FT自旋回波扩散加权图像）在活猫脑。由于这些参数对组织结构变化的高固有灵敏度（即，大分子、细胞、组织和器官结构）和生理状态下，它们的潜在应用包括监测发育、衰老和疾病中的结构变化。(C)出版社：Academic Press，Inc.
Quantitative-diffusion-tensor MRI consists of deriving and displaying parameters that resemble histological or physiological stains, i.e., that characterize intrinsic features of tissue microstructure and microdynamics. Specifically, these parameters are objective, and insensitive to the choice of laboratory coordinate system. Here, these two properties are used to derive intravoxel measures of diffusion isotropy and the degree of diffusion anisotropy, as well as intervoxel measures of structural similarity, and fiber-tract organization from the effective diffusion tensor, (D) under bar, which is estimated in each voxel. First, (D) under bar is decomposed into its isotropic and anisotropic parts, [D] (I) under bar and (D) under bar - [D] (I) under bar, respectively (where [D] = Trace((D) under bar)/3 is the mean diffusivity, and (I) under bar is the identity tensor). Then, the tensor (dot) product operator is used to generate a family of new rotationally and translationally invariant quantities. Finally, maps of these quantitative parameters are produced from high-resolution diffusion tensor images (in which (D) under bar is estimated in each voxel from a series of 2D-FT spin-echo diffusion-weighted images) in living cat brain. Due to the high inherent sensitivity of these parameters to changes in tissue architecture (i.e., macromolecular, cellular, tissue, and organ structure) and in its physiologic state, their potential applications include monitoring structural changes in development, aging, and disease. (C) 1996 Academic Press, Inc.