Quantitative magnetization transfer characteristics of the human cervical spinal cord in vivo: application to adrenomyeloneuropathy.

TitleQuantitative magnetization transfer characteristics of the human cervical spinal cord in vivo: application to adrenomyeloneuropathy.
Publication TypeJournal Article
Year of Publication2009
AuthorsSmith SA, Golay X, Fatemi A, Mahmood A, Raymond GV, Moser HW, van Zijl PCM, Stanisz GJ
JournalMagnetic resonance in medicine : official journal of the Society of Magnetic Resonance in Medicine / Society of Magnetic Resonance in Medicine
Volume61
Issue1
Pagination22-7
Date Published2009 Jan
Abstract

Magnetization transfer (MT) imaging has assessed myelin integrity in the brain and spinal cord; however, quantitative MT (qMT) has been confined to the brain or excised tissue. We characterized spinal cord tissue with qMT in vivo, and as a first application, qMT-derived metrics were examined in adults with the genetic disorder Adrenomyeloneuropathy (AMN). AMN is a progressive disease marked by demyelination of the white matter tracts of the cervical spinal cord, and a disease in which conventional MRI has been limited. MT data were acquired at 1.5 Tesla using 10 radiofrequency offsets at one power in the cervical cord at C2 in 6 healthy volunteers and 9 AMN patients. The data were fit to a two-pool MT model and the macromolecular fraction (M(ob)), macromolecular transverse relaxation time (T(2b)) and the rate of MT exchange (R) for lateral and dorsal column white matter and gray matter were calculated. M(ob) for healthy volunteers was: WM = 13.9 +/- 2.3%, GM = 7.9 +/- 1.5%. In AMN, dorsal column M(ob) was significantly decreased (P < 0.03). T(2b) for volunteers was: 9 +/- 2 micros and the rate of MT exchange (R) was: WM = 56 +/- 11 Hz, GM = 67 +/- 12 Hz. Neither T(2b) nor R showed significant differences between healthy and diseased cords. Comparisons are made between qMT, and conventional MT acquisitions.

DOI10.1242/jcs.031427
Alternate JournalMagn Reson Med