基于相位共轭对称的GRAPPA并行成像算法研究  

Research on GRAPPA Parallel Imaging Algorithm Based on Phase-Conjugate Symmetry

作　　者：王艳飞 郑潘 WANG Yan-fei;ZHENG Pan(School of Electronics&Information Engineering,Liaoning University of Technology,Jinzhou 121001,China)

机构地区：[1]辽宁工业大学电子与信息工程学院,辽宁锦州121001

出　　处：《辽宁工业大学学报（自然科学版）》2024年第5期281-285,共5页Journal of Liaoning University of Technology(Natural Science Edition)

基　　金：2024年辽宁省教育厅高等学校基本科研项目(LJ212410154020)。

摘　　要：为了提高GRAPPA并行成像算法的图像质量,提出了一种基于k空间相位共轭对称的GRAPPA并行成像算法。该算法首先把k空间分成两个区域:GRAPPA并行采样区和未采样区。其中GRAPPA并行采样区以常规的GRAPPA算法为基础进行数据重建。为提高重建算法的稳定性,在GRAPPA重建时引入了Tikhonov正则化因子。对未采样区利用k空间的相位共轭对称特性进行数据重建。在1.5 T超导磁共振成像系统中对算法进行了验证,相位共轭对称GRAPPA算法图像的伪影降低了16.8%,而算法对图像信噪比没有显著影响。实验结果表明,所提出的方法可以有效抑制GRAPPA并行重建伪影,提高图像质量。In order to improve the GRAPPA image quality,a parallel GRAPPA method based on k-space phase conjugate symmetry is proposed.The method divides the k-space into two parts:the parallel GRAPPA sampled region and unsampled region.The parallel GRAPPA sampled region is based on conventional GRAPPA algorithm for data reconstruction.To improve the stability of reconstruction algorithm,the Tikhonov regularization factor was introduced during GRAPPA reconstruction.For the unsampled region,the phase conjugate symmetry property of k-space is used for data reconstruction.The method is tested and validated on a 1.5T superconducting MRI scanner,the image artifact was reduced by 16.8%,while the method has no significant impact on the image signal-to-noise ratio.The experimental results show that the proposed method can effectively suppress GRAPPA artifacts and improve the image quality.

关 键 词：磁共振并行成像 GRAPPA K空间 相位共轭对称 

分 类 号：TP197.39[自动化与计算机技术—控制理论与控制工程]