title: Highly undersampled MR image reconstruction using an improved dual-dictionary learning method with self-adaptive dictionaries.
abstract: Dual-dictionary learning (Dual-DL) method utilizes both a low-resolution dictionary and a high-resolution dictionary, which are co-trained for sparse coding and image updating, respectively. It can effectively exploit a priori knowledge regarding the typical structures, specific features, and local details of training sets images. The prior knowledge helps to improve the reconstruction quality greatly. This method has been successfully applied in magnetic resonance (MR) image reconstruction. However, it relies heavily on the training sets, and dictionaries are fixed and nonadaptive. In this research, we improve Dual-DL by using self-adaptive dictionaries. The low- and high-resolution dictionaries are updated correspondingly along with the image updating stage to ensure their self-adaptivity. The updated dictionaries incorporate both the prior information of the training sets and the test image directly. Both dictionaries feature improved adaptability. Experimental results demonstrate that the proposed method can efficiently and significantly improve the quality and robustness of MR image reconstruction.
authors.affiliation: School of Biomedical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Rd., Minhang, Shanghai, 200240, China.
authors.forename: Jiansen
authors.initials: J
authors.lastname: Li
authors.affiliation: Department of Radiation Oncology, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Song
authors.affiliation: Department of Radiology, Children's Hospital of Shanghai, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Zhu
authors.affiliation: School of Biomedical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Rd., Minhang, Shanghai, 200240, China. junzhao@sjtu.edu.cn.
authors.forename: Jun
authors.initials: J
authors.lastname: Zhao
mesh_terms: D001921:Brain / Q000502:physiology; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D007858:Learning; D008279:Magnetic Resonance Imaging / Q000379:methods*
keywords: Compressed sensing; Dual-dictionary learning; Image reconstruction; Magnetic resonance imaging; Self-adaptive dictionary