Title
Learning Compact Q-Space Representations For Multi-Shell Diffusion-Weighted Mri
Abstract
Diffusion-weighted MRI measures the direction and scale of the local diffusion process in every voxel through its spectrum in q-space, typically acquired in one or more shells. Recent developments in microstructure imaging and multi-tissue decomposition have sparked renewed attention in the radial b-value dependence of the signal. Applications in motion correction and outlier rejection, therefore, require a compact linear signal representation that extends over the radial as well as angular domain. Here, we introduce SHARD, a data-driven representation of the q-space signal based on spherical harmonics and a radial decomposition into orthonormal components. This representation provides a complete, orthogonal signal basis, tailored to the spherical geometry of q-space, and calibrated to the data at hand. We demonstrate that the rank-reduced decomposition outperforms model-based alternatives in human brain data, while faithfully capturing the micro- and meso-structural information in the signal. Furthermore, we validate the potential of joint radial-spherical as compared with single-shell representations. As such, SHARD is optimally suited for applications that require low-rank signal predictions, such as motion correction and outlier rejection. Finally, we illustrate its application for the latter using outlier robust regression.
Year
DOI
Venue
2019
10.1109/TMI.2018.2873736
IEEE TRANSACTIONS ON MEDICAL IMAGING
Keywords
Field
DocType
Diffusion-weighted imaging, multi-shell HARDI, blind source separation, dimensionality reduction
Voxel,Computer vision,Dimensionality reduction,Spherical harmonics,Outlier,Algorithm,Spherical geometry,Shard,Orthonormal basis,Artificial intelligence,Blind signal separation,Mathematics
Journal
Volume
Issue
ISSN
38
3
0278-0062
Citations 
PageRank 
References 
0
0.34
0
Authors
7
Name
Order
Citations
PageRank
Daan Christiaens12129.23
Lucilio Cordero-Grande214016.15
Jana Hutter373.47
Anthony N Price425315.32
Maria Deprez512.38
Jo Hajnal61796119.03
Jacques-Donald Tournier7101461.91