title: Morphology enabled dipole inversion for quantitative susceptibility mapping using structural consistency between the magnitude image and the susceptibility map.
abstract: The magnetic susceptibility of tissue can be determined in gradient echo MRI by deconvolving the local magnetic field with the magnetic field generated by a unit dipole. This Quantitative Susceptibility Mapping (QSM) problem is unfortunately ill-posed. By transforming the problem to the Fourier domain, the susceptibility appears to be undersampled only at points where the dipole kernel is zero, suggesting that a modest amount of additional information may be sufficient for uniquely resolving susceptibility. A Morphology Enabled Dipole Inversion (MEDI) approach is developed that exploits the structural consistency between the susceptibility map and the magnitude image reconstructed from the same gradient echo MRI. Specifically, voxels that are part of edges in the susceptibility map but not in the edges of the magnitude image are considered to be sparse. In this approach an L1 norm minimization is used to express this sparsity property. Numerical simulations and phantom experiments are performed to demonstrate the superiority of this L1 minimization approach over the previous L2 minimization method. Preliminary brain imaging results in healthy subjects and in patients with intracerebral hemorrhages illustrate that QSM is feasible in practice.
authors.affiliation: Department of Radiology, Weill Medical College of Cornell University, New York, NY 10022, USA.
authors.forename: Jing
authors.initials: J
authors.lastname: Liu
authors.forename: Tian
authors.initials: T
authors.lastname: Liu
authors.forename: Ludovic
authors.initials: L
authors.lastname: de Rochefort
authors.forename: James
authors.initials: J
authors.lastname: Ledoux
authors.forename: Ildar
authors.initials: I
authors.lastname: Khalidov
authors.forename: Weiwei
authors.initials: W
authors.lastname: Chen
authors.forename: A John
authors.initials: AJ
authors.lastname: Tsiouris
authors.forename: Cynthia
authors.initials: C
authors.lastname: Wisnieff
authors.forename: Pascal
authors.initials: P
authors.lastname: Spincemaille
authors.forename: Martin R
authors.initials: MR
authors.lastname: Prince
authors.forename: Yi
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000328:Adult; D000465:Algorithms; D001930:Brain Injuries / Q000473:pathology; D001931:Brain Mapping / Q000379:methods*; D003198:Computer Simulation; D017352:Echo-Planar Imaging; D004574:Electromagnetic Fields; D005583:Fourier Analysis; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D007091:Image Processing, Computer-Assisted; D020300:Intracranial Hemorrhages / Q000473:pathology; D019047:Phantoms, Imaging; D015203:Reproducibility of Results