Hori Masaaki, Kamiya Kouhei, Murata Katsutoshi
Department of Radiology, Toho University Omori Medical Center, 6-11-1 Omorinishi, Ota-ku, Tokyo 143-8541, Japan.
Department of Radiology, Toho University Omori Medical Center, 6-11-1 Omorinishi, Ota-ku, Tokyo 143-8541, Japan.
Magn Reson Imaging Clin N Am. 2021 May;29(2):129-136. doi: 10.1016/j.mric.2021.01.001. Epub 2021 Mar 23.
Diffusion-weighted images provide a unique contrast that shows the ability to assess tissue structure and condition on a micrometer scale. Notably, these equations are necessary to understand diffusion MR imaging as a theory but not for real imaging, particularly in clinical practice. The diffusion phenomenon can be observed only through MR measurements. One of the emerging fields of diffusion MRI is to probe the tissue microstructure by altering the diffusion time t, the time interval over which spin displacements are sampled. However, the diffusion time is, in a sense, more important than the b-value for diffusion-weighted images and their quantitative metrics.
扩散加权成像提供了一种独特的对比度,能够在微米尺度上评估组织结构和状况。值得注意的是,这些方程对于将扩散磁共振成像理解为一种理论是必要的,但对于实际成像,尤其是在临床实践中并非如此。扩散现象只能通过磁共振测量来观察。扩散磁共振成像的一个新兴领域是通过改变扩散时间t(即对自旋位移进行采样的时间间隔)来探测组织微观结构。然而,从某种意义上说,扩散时间对于扩散加权图像及其定量指标比b值更为重要。