Multiexponential T2 and magnetization transfer MRI of demyelination and remyelination in murine spinal cord

Neuroimage. 2009 May 1;45(4):1173-82. doi: 10.1016/j.neuroimage.2008.12.071. Epub 2009 Jan 21.

Abstract

Identification of remyelination is important in the evaluation of potential treatments of demyelinating diseases such as multiple sclerosis. Local injection of lysolecithin into the brain or spinal cord provides a murine model of demyelination with spontaneous remyelination. The aim of this study was to determine if quantitative, multicomponent T(2) (qT(2)) analysis and magnetization transfer ratio (MTR), both indicative of myelin content, could detect changes in myelination, particularly remyelination, of the cervical spinal cord in mice treated with lysolecithin. We found that the myelin water fraction and geometric mean T(2) value of the intra/extracellular water significantly decreased at 14 days then returned to control levels by 28 days after injury, corresponding to clearance of myelin debris and remyelination which was shown by eriochrome cyanine and oil red O staining of histological sections. The MTR was significantly decreased 14 days after lysolecithin injection, and remained low over the time course studied. Evidence of demyelination shown by both qT(2) and MTR lagged behind the histological evidence of demyelination. Myelin water fraction increased with remyelination, however MTR remained lower after 28 days. The difference between qT(2) and MTR may identify early remyelination.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Demyelinating Diseases / chemically induced*
  • Demyelinating Diseases / pathology*
  • Image Enhancement / methods
  • Image Interpretation, Computer-Assisted / methods*
  • Lysophosphatidylcholines*
  • Magnetic Resonance Imaging / methods*
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Nerve Fibers, Myelinated / drug effects
  • Nerve Fibers, Myelinated / pathology*
  • Nerve Regeneration*
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Spinal Cord / drug effects
  • Spinal Cord / pathology*

Substances

  • Lysophosphatidylcholines