QSMART: Quantitative susceptibility mapping artifact reduction technique

• Published in: NeuroImage (Orlando, Fla.) Vol. 231; p. 117701
• Main Authors: Yaghmaie, Negin, Syeda, Warda T., Wu, Chengchuan, Zhang, Yicheng, Zhang, Tracy D., Burrows, Emma L., Brodtmann, Amy, Moffat, Bradford A., Wright, David K., Glarin, Rebecca, Kolbe, Scott, Johnston, Leigh A.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.05.2021; Elsevier Limited; Elsevier
• Subjects: Algorithms; Alzheimer's disease; Artifact suppression; Biomarkers; Brain mapping; Interfaces; Ischemia; Magnetic fields; Magnetic resonance imaging; Mapping; Methods; Quantitative Susceptibility Mapping; Spatially dependent filtering; Streaking artifacts; Susceptibility; Two-stage parallel inversion; Veins & arteries; Two-stage parallel inversion; Quantitative Susceptibility Mapping; Spatially dependent filtering; Streaking artifacts; Artifact suppression
• ISSN: 1053-8119; 1095-9572
• DOI: 10.1016/j.neuroimage.2020.117701

•QSMART is a two-stage QSM inversion pipeline that suppresses artifacts induced by high-susceptibility veins and cortical air-tissue interface.•Spatially dependent filtering is applied to a combined cortical surface and vasculature mask as part of the QSMART pipeline, eliminating the need for the cortical erosion step of SHARP-based methods.•QSMART shows superior artifact suppression on 7T human, 9.4T mouse, and 4.7T rat data compared to the previous methods.•The QSMART pipeline code is publicly available and the artifact-suppressed susceptibility maps generated by QSMART are well suited to studies of neurodegenerative diseases that require robust and non-eroded cortical susceptibility estimates. Purpose: Quantitative susceptibility mapping (QSM) is a novel MR technique that allows mapping of tissue susceptibility values from MR phase images. QSM is an ill-conditioned inverse problem, and although several methods have been proposed in the field, in the presence of a wide range of susceptibility sources, streaking artifacts appear around high susceptibility regions and contaminate the whole QSM map. QSMART is a post-processing pipeline that uses two-stage parallel inversion to reduce the streaking artifacts and remove banding artifact at the cortical surface and around the vasculature. Method: Tissue and vein susceptibility values were separately estimated by generating a mask of vasculature driven from the magnitude data using a Frangi filter. Spatially dependent filtering was used for the background field removal step and the two susceptibility estimates were combined in the final QSM map. QSMART was compared to RESHARP/iLSQR and V-SHARP/iLSQR inversion in a numerical phantom, 7T in vivo single and multiple-orientation scans, 9.4T ex vivo mouse data, and 4.7T in vivo rat brain with induced focal ischemia. Results: Spatially dependent filtering showed better suppression of phase artifacts near cortex compared to RESHARP and V-SHARP, while preserving voxels located within regions of interest without brain edge erosion. QSMART showed successful reduction of streaking artifacts as well as improved contrast between different brain tissues compared to the QSM maps obtained by RESHARP/iLSQR and V-SHARP/iLSQR. Conclusion: QSMART can reduce QSM artifacts to enable more robust estimation of susceptibility values in vivo and ex vivo.