Simultaneous and inherent correction of B0 and eddy-current induced distortions in high-resolution diffusion MRI using reversed polarity gradients and multiplexed sensitivity encoding (RPG-MUSE).
Simultaneous and inherent correction of B0 and eddy-current induced distortions in high-resolution diffusion MRI using reversed polarity gradients and multiplexed sensitivity encoding (RPG-MUSE).
复制标题
使用反向极性梯度和多路复用灵敏度编码 (RPG-MUSE) 对高分辨率扩散 MRI 中的 B0 和涡流引起的畸变进行同步和固有校正。
DOI：
10.1016/j.neuroimage.2018.09.055
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发表时间：
2018
期刊：
影响因子：
5.7
通讯作者：
Song,AllenW
中科院分区：
文献类型：
--
作者：
Bruce,IainP;Petty,Christopher;Song,AllenW
在扩散磁共振成像（dMRI）中，静态磁场（B0）的不均匀性和时变梯度涡流会引起重建图像的空间畸变。当使用高空间分辨率时，这些失真会加剧，并且许多基于场测绘的校正技术通常只获得静态b - 0失真的地图，这不足以校正涡流引起的图像失真。本文提出了一种称为RPG-MUSE的新技术，通过将反极性梯度（RPG）集成到复用灵敏度编码（MUSE）中使用的多镜头回波平面成像获取方案中，实现无失真的高分辨率弥散MRI。通过在基线和扩散加权采集的拍摄之间交替相位编码方向，无需额外的数据采集，就可以固有地推导出静态b0和涡流感应场不均匀性的图。通过二维和三维编码的dMRI采集，表明RPG-MUSE重建可以同时实现高空间分辨率、高空间保真度以及随后的高扩散指标精度。
In diffusion MRI (dMRI), static magnetic field (B0) inhomogeneity and time varying gradient eddy currents induce spatial distortions in reconstructed images. These distortions are exacerbated when high spatial resolutions are used, and many field-mapping based correction techniques often only acquire maps of static B0distortion, which are not adequate for correcting eddy current induced image distortions. This report presents a novel technique, termed RPG-MUSE, for achieving distortion-free high-resolution diffusion MRI by integrating reversed polarity gradients (RPG) into the multi-shot echo planar imaging acquisition scheme used in multiplexed sensitivity encoding (MUSE). By alternating the phase encoding direction between shots in both baseline and diffusion-weighted acquisitions, maps of both static B0and eddy current induced field inhomogeneities can be inherently derived, without the need for additional data acquisition. Through both 2D and 3D encoded dMRI acquisitions, it is shown that an RPG-MUSE reconstruction can simultaneously achieve high spatial resolution, high spatial fidelity, and subsequently, high accuracy in diffusion metrics.