title: High-resolution human cervical spinal cord imaging at 7 T.
abstract: We present high-resolution anatomical imaging of the cervical spinal cord in healthy volunteers at the ultrahigh field of 7 T with a prototype four-channel radiofrequency coil array, in comparison with 3-T imaging of the same subjects. Signal-to-noise ratios at both field strengths were estimated using the rigorous Kellman method. Spinal cord cross-sectional area measurements were performed, including whole-cord measurements at both fields and gray matter segmentation at 7 T. The 7-T array coil showed reduced sagittal coverage, comparable axial coverage and the expected significantly higher signal-to-noise ratio compared with equivalent 3-T protocols. In the cervical spinal cord, the signal-to-noise ratio was found by the Kellman method to be higher by a factor of 3.5 with the 7-T coil than with standard 3-T coils. Cervical spine imaging in healthy volunteers at 7 T revealed not only detailed white/gray matter differentiation, but also structures not visualized at lower fields, such as denticulate ligaments, nerve roots and rostral-caudal blood vessels. Whole-cord cross-sectional area measurements showed good agreement at both field strengths. The measurable gray/white matter cross-sectional areas at 7 T were found to be comparable with reports from histology. These pilot data demonstrate the use of higher signal-to-noise ratios at the ultrahigh field of 7 T for significant improvement in anatomical resolution of the cervical spinal cord, allowing the visualization of structures not seen at lower field strength, particularly for axial imaging.
authors.affiliation: Department of Radiology, New York University Langone Medical Center, New York, NY, USA. eric.sigmund@nyumc.org
authors.forename: E E
authors.initials: EE
authors.lastname: Sigmund
authors.forename: G A
authors.initials: GA
authors.lastname: Suero
authors.forename: C
authors.initials: C
authors.lastname: Hu
authors.forename: K
authors.initials: K
authors.lastname: McGorty
authors.forename: D K
authors.initials: DK
authors.lastname: Sodickson
authors.forename: G C
authors.initials: GC
authors.lastname: Wiggins
authors.forename: J A
authors.initials: JA
authors.lastname: Helpern
mesh_terms: D000328:Adult; D002574:Cervical Vertebrae; D005260:Female; D006801:Humans; D007089:Image Enhancement; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D059629:Signal-To-Noise Ratio; D013116:Spinal Cord / Q000033:anatomy & histology*