J Shanghai Jiaotong Univ Sci ›› 2025, Vol. 30 ›› Issue (3): 499-509.doi: 10.1007/s12204-023-2647-2

• Medicine-Engineering Interdisciplinary • Previous Articles     Next Articles

Fast Parallel Magnetic Resonance Imaging Reconstruction Based on Sparsifying Transform Learning and Structured Low-Rank Model

基于变换学习和结构化低秩模型的并行成像快速重构算法

段继忠,徐昱含,黄欢   

  1. Faculty of Information Engineering and Automation, Kunming University of Science and Technology, Kunming 650500, China
  2. 昆明理工大学 信息工程与自动化学院,昆明 650500
  • Received:2022-08-10 Accepted:2022-12-24 Online:2025-06-06 Published:2025-06-06

Abstract: The structured low-rank model for parallel magnetic resonance (MR) imaging can efficiently reconstruct MR images with limited auto-calibration signals. To improve the reconstruction quality of MR images, we integrate the joint sparsity and sparsifying transform learning (JTL) into the simultaneous auto-calibrating and k-space estimation (SAKE) structured low-rank model, named JTLSAKE. The alternate direction method of multipliers is exploited to solve the resulting optimization problem, and the optimized gradient method is used to improve the convergence speed. In addition, a graphics processing unit is used to accelerate the proposed algorithm. The experimental results on four in vivo human datasets demonstrate that the reconstruction quality of the proposed algorithm is comparable to that of JTL-based low-rank modeling of local k-space neighborhoods with parallel imaging (JTL-PLORAKS), and the proposed algorithm is 46 times faster than the JTL-PLORAKS, requiring only 4 s to reconstruct a 200 × 200 pixels MR image with 8 channels.

Key words: structured low-rank, parallel magnetic resonance imaging, sparsifying transform learning, alternating direction method of multipliers, optimized gradient method

摘要: 结构化低秩并行磁共振成像模型在自校准信号受限的情况下,可以有效地重构出磁共振图像,但其计算量大导致重构时间长,而难以得到临床应用。为了提高并行磁共振图像的重构质量和重构速度,将联合稀疏变换学习(JTL)与SAKE结构化低秩重构模型结合,使用交替方向乘子法对模型进行求解,并引入优化梯度法提高收敛速度。另外,使用图形处理器进行加速,从而得到一种并行磁共振成像快速重构算法JTLSAKE。通过对四组人类活体的并行磁共振成像数据集进行重构实验可以看出,提出的JTLSAKE算法可以获得与基于JTL的PLORAKS算法相当的重构质量,并且重构速度提高了43倍以上,重构200×200 pixels的8通道磁共振图像仅需4 s。

关键词: 结构化低秩,并行磁共振成像,联合稀疏变换学习,交替方向乘子法,优化梯度法

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