Zhang Ling, Kholmovski Eugene G, Guo Junyu, Parker Dennis L
Department of Electrical and Computer Engineering, University of Utah, Salt Lake City, Utah, USA.
J Magn Reson Imaging. 2007 Jun;25(6):1271-82. doi: 10.1002/jmri.20908.
To detect motion-corrupted measurements in multi-average turbo-spin-echo (TSE) acquisitions and reduce motion artifacts in reconstructed images.
An average-specific phase encoding (PE) ordering scheme was developed for multi-average TSE sequences in which each echo train is assigned a unique PE pattern for each pre-averaged image (PAI). A motion detection algorithm is developed based on this new PE ordering to identify which echo trains in which PAIs are motion-corrupted. The detected PE views are discarded and replaced by uncorrupted k-space data of the nearest PAI. Both phantom and human studies were performed to investigate the effectiveness of motion artifact reduction using the proposed method.
Motion-corrupted echo trains were successfully detected in all phantom and human experiments. Significant motion artifact suppression has been achieved for most studies. The residual artifacts in the reconstructed images are mainly caused by residual inconsistencies that remain after the corrupted k-space data is corrected.
The proposed method combines a novel data acquisition scheme, a robust motion detection algorithm, and a simple motion correction algorithm. It is effective in reducing motion artifacts for images corrupted by either bulk motion or local motion that occasionally happens during data acquisition.
在多次平均快速自旋回波（TSE）采集中检测运动干扰测量值，并减少重建图像中的运动伪影。
为多次平均TSE序列开发了一种特定平均相位编码（PE）排序方案，其中每个回波链为每个预平均图像（PAI）分配一个独特的PE模式。基于这种新的PE排序开发了一种运动检测算法，以识别哪些PAI中的哪些回波链受到运动干扰。检测到的PE视图被丢弃，并用最近PAI的未受干扰的k空间数据替换。进行了体模和人体研究，以研究所提出方法减少运动伪影的有效性。
在所有体模和人体实验中均成功检测到受运动干扰的回波链。大多数研究都实现了显著的运动伪影抑制。重建图像中的残留伪影主要是由校正受干扰的k空间数据后仍存在的残留不一致性引起的。
所提出的方法结合了一种新颖的数据采集方案、一种强大的运动检测算法和一种简单的运动校正算法。它对于减少因数据采集期间偶尔发生的整体运动或局部运动而受损的图像中的运动伪影是有效的。
