Efficient multiple acquisitions by skipped phase encoding and edge deghosting (SPEED) using shared spatial information
Efficient multiple acquisitions by skipped phase encoding and edge deghosting (SPEED) using shared spatial information
复制标题
DOI：
10.1002/mrm.21809
复制
发表时间：
2009-01
影响因子：
3.3
通讯作者：
Z. Chang;Q. Xiang;J. Ji;F. Yin
中科院分区：
文献类型：
--
作者：
Z. Chang;Q. Xiang;J. Ji;F. Yin
进一步发展了跳过相位编码和边缘去重像(SPEED)的快速MRI方法，以加速多次采集。在单次采集中，SPEED首先采集三个欠采样因子为N/3的稀疏重影边缘图，它们采用双层结构建模，并由三个带有两个未知重影的方程描述，每个方程具有唯一的重影顺序索引。通过最小化最小二乘误差，确定了一对鬼序索引。基于它们，两个相应的鬼影被解析，从而产生去鬼影图像。在这种情况下，需要三个方程来确定重影顺序指数，而只需要两个方程来解析两个重影。这既显示了效率低下，也显示了潜力。多个采集通常包含相似的空间信息。这些相似性可用于通过在不同收购之间共享幽灵顺序指数来提高效率，从而导致比单一收购更大的加速系数。《医学评论》61：229-233,2009。©2008 Wiley-Liss，Inc.
The fast MRI method of Skipped Phase Encoding and Edge Deghosting (SPEED) is further developed to accelerate multiple acquisitions. In a single acquisition, SPEED first acquires three sparse ghosted edge maps with an undersampling factor of N/3, which are modeled with a double‐layer structure and described by three equations with two unknown ghosts, each with a unique ghost order index. By minimizing least‐square‐error, a pair of ghost order indexes is determined. Based on them, the two corresponding ghosts are resolved, leading to a deghosted image. In this case, three equations are needed to determine the ghost order index, while only two equations are required to resolve the two ghosts. This shows both inefficiency and potential. Multiple acquisitions often contain similar spatial information. The similarities can be used to improve efficiency by sharing the ghost order index among different acquisitions, leading to acceleration factors greater than that achievable with single acquisition. Magn Reson Med 61:229–233, 2009. © 2008 Wiley‐Liss, Inc.