Title | Calculation of susceptibility through multiple orientation sampling (COSMOS): a method for conditioning the inverse problem from measured magnetic field map to susceptibility source image in MRI. |
Publication Type | Journal Article |
Year of Publication | 2009 |
Authors | Liu T, Spincemaille P, de Rochefort L, Kressler B, Wang Y |
Journal | Magn Reson Med |
Volume | 61 |
Issue | 1 |
Pagination | 196-204 |
Date Published | 2009 Jan |
ISSN | 1522-2594 |
Keywords | Algorithms, Computer Simulation, Humans, Image Enhancement, Image Interpretation, Computer-Assisted, Magnetic Resonance Imaging, Magnetics, Models, Biological, Phantoms, Imaging, Reproducibility of Results, Sensitivity and Specificity |
Abstract | Magnetic susceptibility differs among tissues based on their contents of iron, calcium, contrast agent, and other molecular compositions. Susceptibility modifies the magnetic field detected in the MR signal phase. The determination of an arbitrary susceptibility distribution from the induced field shifts is a challenging, ill-posed inverse problem. A method called "calculation of susceptibility through multiple orientation sampling" (COSMOS) is proposed to stabilize this inverse problem. The field created by the susceptibility distribution is sampled at multiple orientations with respect to the polarization field, B(0), and the susceptibility map is reconstructed by weighted linear least squares to account for field noise and the signal void region. Numerical simulations and phantom and in vitro imaging validations demonstrated that COSMOS is a stable and precise approach to quantify a susceptibility distribution using MRI. |
DOI | 10.1002/mrm.21828 |
Alternate Journal | Magn Reson Med |
PubMed ID | 19097205 |
Related Institute:
MRI Research Institute (MRIRI)