Huang Feng, Li Yu, Vijayakumar Sathya, Hertel Sarah, Duensing George R
Advanced Concept Development, Invivo Corp., 3545 SW 47th Ave., Gainesville, FL 32608, USA.
Magn Reson Med. 2008 Mar;59(3):642-9. doi: 10.1002/mrm.21495.
Partially parallel imaging (PPI) is a widely used technique in clinical applications. A limitation of this technique is the strong noise and artifact in the reconstructed images when high reduction factors are used. This work aims to increase the clinical applicability of PPI by improving its performance at high reduction factors. A new concept, image support reduction, is introduced. A systematic filter-design approach for image support reduction is proposed. This approach shows more advantages when used with an important existing PPI technique, GRAPPA. An improved GRAPPA method, high-pass GRAPPA (hp-GRAPPA), was developed based on this approach. The new technique does not involve changing the original GRAPPA kernel and performs reconstruction in almost the same amount of time. Experimentally, it is demonstrated that the reconstructed images using hp-GRAPPA have much lower noise/artifact level than those reconstructed using GRAPPA.
部分并行成像（PPI）是临床应用中广泛使用的技术。该技术的一个局限性是，当使用高缩减因子时，重建图像中会出现强烈的噪声和伪影。这项工作旨在通过提高PPI在高缩减因子下的性能来增加其临床适用性。引入了一个新的概念——图像支撑缩减。提出了一种用于图像支撑缩减的系统滤波器设计方法。当与现有的一种重要PPI技术GRAPPA一起使用时，该方法显示出更多优势。基于此方法开发了一种改进的GRAPPA方法——高通GRAPPA（hp-GRAPPA）。这项新技术不涉及改变原始的GRAPPA内核，并且几乎在相同的时间内进行重建。实验表明，使用hp-GRAPPA重建的图像比使用GRAPPA重建的图像具有低得多的噪声/伪影水平。
