title: High-resolution multi-parametric quantitative magnetic resonance imaging of the human cervical spinal cord at 7T.
abstract: Quantitative MRI techniques have the potential to characterize spinal cord tissue impairments occurring in various pathologies, from both microstructural and functional perspectives. By enabling very high image resolution and enhanced tissue contrast, ultra-high field imaging may offer further opportunities for such characterization. In this study, a multi-parametric high-resolution quantitative MRI protocol is proposed to characterize in vivo the human cervical spinal cord at 7T. Multi-parametric quantitative MRI acquizitions including T1, T2*relaxometry mapping and axial diffusion MRI were performed on ten healthy volunteers with a whole-body 7T system using a commercial prototype coil-array dedicated to cervical spinal cord imaging. Automatic cord segmentation and multi-parametric data registration to spinal cord templates enabled robust regional studies within atlas-based WM tracts and GM horns at the C3 cervical level. T1value, cross-sectional area and GM/WM ratio evolutions along the cervical cord were also reported. An original correction method for B1+-biased T1mapping sequence was additionally proposed and validated on phantom. As a result, relaxometry and diffusion parameters derived from high-resolution quantitative MRI acquizitions were reported at 7T for the first time. Obtained images, with unmatched resolutions compared to lower field investigations, provided exquisite anatomical details and clear delineation of the spinal cord substructures within an acquisition time of 30min, compatible with clinical investigations. Regional statistically significant differences were highlighted between WM and GM based on T1and T2* maps (p<10-3), as well as between sensory and motor tracts based on diffusion tensor imaging maps (p<0.05). The proposed protocol demonstrates that ultra-high field spinal cord high-resolution quantitative MRI is feasible and lays the groundwork for future clinical investigations of degenerative spinal cord pathologies.
authors: Aix Marseille Université, CNRS, CRMBM UMR 7339, 13385 Marseille, France; AP-HM, Hôpital de la Timone, Pôle d'imagerie médicale, CEMEREM, 13005 Marseille, France; iLab-Spine - Laboratoire international - Imagerie et Biomécanique du rachis, France/Canada.
authors: Aurélien
authors: A
authors: Massire
authors: Aix Marseille Université, CNRS, CRMBM UMR 7339, 13385 Marseille, France; AP-HM, Hôpital de la Timone, Pôle d'imagerie médicale, CEMEREM, 13005 Marseille, France; iLab-Spine - Laboratoire international - Imagerie et Biomécanique du rachis, France/Canada; Aix-Marseille Université, IFSTTAR, LBA UMR T24, 13015 Marseille, France.
authors: Manuel
authors: M
authors: Taso
authors: Aix Marseille Université, CNRS, CRMBM UMR 7339, 13385 Marseille, France; AP-HM, Hôpital de la Timone, Pôle d'imagerie médicale, CEMEREM, 13005 Marseille, France.
authors: Pierre
authors: P
authors: Besson
authors: Aix Marseille Université, CNRS, CRMBM UMR 7339, 13385 Marseille, France; AP-HM, Hôpital de la Timone, Pôle d'imagerie médicale, CEMEREM, 13005 Marseille, France.
authors: Maxime
authors: M
authors: Guye
authors: Aix Marseille Université, CNRS, CRMBM UMR 7339, 13385 Marseille, France; AP-HM, Hôpital de la Timone, Pôle d'imagerie médicale, CEMEREM, 13005 Marseille, France.
authors: Jean-Philippe
authors: JP
authors: Ranjeva
authors: Aix Marseille Université, CNRS, CRMBM UMR 7339, 13385 Marseille, France; AP-HM, Hôpital de la Timone, Pôle d'imagerie médicale, CEMEREM, 13005 Marseille, France; iLab-Spine - Laboratoire international - Imagerie et Biomécanique du rachis, France/Canada. Electronic address: virginie.callot@univ-amu.fr.
authors: Virginie
authors: V
authors: Callot
mesh_terms: D000328:Adult; D066193:Cervical Cord / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D056324:Diffusion Tensor Imaging / Q000379:methods; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D055815:Young Adult
keywords: Diffusion tensor imaging; Quantitative MRI; Relaxometry mapping; Spinal cord; Template-based segmentation; Ultra-high field