Julien Cohen-Adad1,2, Henrik Lundell3,4, Serge Rossignol2
1INSERM, Univ Paris 6, Pitie Salpetriere Hospital, Paris, France; 2GRSNC, Physiology department, Univ Montreal, Montreal, QC, Canada; 3Danish Research Center for MR, Copenhagen University Hospital, Hvidovre, Denmark; 4Inst. Neurosci & Pharmacol, Univ Copenhagen, Copenhagen N, Denmark
Susceptibility artifacts induced by B0-field inhomogeneities are particularly problematic in spinal cord EPI, inducing large geometric and intensity distortions. There exists a variety of approaches to correct for distortions a posteriori. In this study, we compare some of them, including the phase field map, the reversed gradient, the point spread function (PSF) and the co-registration methods. We show that the reverse gradient and PSF approaches yield best results towards large (lower cervical cord) and small (inter-vertebral disks) distortion patterns. This study also investigates the impact of distortion correction on diffusion tensor imaging of the human spinal cord.
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