DECT-MULTRA: Dual-Energy CT Image Decomposition With Learned Mixed Material Models and Efficient Clustering

Journal Article · 01 April 2020 · IEEE Transactions on Medical Imaging

DOI: https://doi.org/10.1109/tmi.2019.2946177 · OSTI ID:1768537

Li, Zhipeng  ^[1]; Ravishankar, Saiprasad  ^[2]; Long, Yong  ^[1]; Fessler, Jeffrey A.  ^[3]

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1. Univ. of Michigan, Ann Arbor, MI (United States); Shanghai Jiao Tong Univ. (China)
2. Michigan State Univ., East Lansing, MI (United States)
3. Univ. of Michigan, Ann Arbor, MI (United States)

Dual-energy computed tomography (DECT) imaging plays an important role in advanced imaging applications due to its material decomposition capability. Image-domain decomposition operates directly on CT images using linear matrix inversion, but the decomposed material images can be severely degraded by noise and artifacts. This paper proposes a new method dubbed DECT-MULTRA for image-domain DECT material decomposition that combines conventional penalized weighted-least squares (PWLS) estimation with regularization based on a mixed union of learned transforms (MULTRA) model. Our proposed approach pre-learns a union of common-material sparsifying transforms from patches extracted from all the basis materials, and a union of cross-material sparsifying transforms from multi-material patches. The common-material transforms capture the common properties among different material images, while the cross-material transforms capture the cross-dependencies. The proposed PWLS formulation is optimized efficiently by alternating between an image update step and a sparse coding and clustering step, with both of these steps having closed-form solutions. The effectiveness of our method is validated with both XCAT phantom and clinical head data. The results demonstrate that our proposed method provides superior material image quality and decomposition accuracy compared to other competing methods.

• Research Organization: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
• Sponsoring Organization: USDOE
• Grant/Contract Number: 89233218CNA000001
• OSTI ID: 1768537
• Report Number(s): LA-UR-18-31890
• Journal Information: IEEE Transactions on Medical Imaging, Vol. 39, Issue 4; ISSN 0278-0062
• Publisher: IEEECopyright Statement
• Country of Publication: United States
• Language: English