Retrograde axonal tracing using manganese enhanced magnetic resonance imaging

Ken Matsuda, Gary F. Egan

Research output: Chapter in Book/Report/Conference proceedingChapter (Book)Researchpeer-review

Abstract

The rat sciatic nerve model combined with manganese-enhanced magnetic resonance imaging (MEMRI) was used to investigate retrograde axonal transport to assess its clinical potential to examine peripheral nerve injury without sacrificing the animals. The right sciatic nerve was exposed and crushed. After each recovery period, the distal part of the right sciatic nerve was injected with manganese solution. After allowing 3 days for manganese transport the animals were subsequently scanned to visualize the sciatic nerve and its corresponding spinal cord and dorsal root ganglia with T1-weighted MRI. The animals were randomly divided into 4 experimental groups according to their recovery period post-crush injury: 3 days, 2 weeks, 4 weeks and 12 weeks; and two control groups: a non-crushed group and a nerve cut group. In the no-injury group, the right sciatic nerve tract including its corresponding spinal cord and dorsal root ganglia showed significant T1 signal enhancement. In the animals with crush injury, the MR signal intensity was significantly reduced proximal to the injured site but gradually reappeared with increasing recovery period. The signal intensity of the sciatic tract was compared to the results of behavioral functional testing, retrograde axonal tracing with neural tracer fluorogold and histomorphometric analysis of the distal nerve. Significant correlations were observed between the MR signal intensity and the behavioral functional test and the retrograde axonal tracing with fluorogold. These results from rat sciatic nerve model show that retrograde neuronal tract tracing with MEMRI can be used for the assessment of peripheral nerve damage and regeneration and also suggest the clinical potential as a specific, sensitive and noninvasive assessment of peripheral nerve injury and regeneration.

Original languageEnglish
Title of host publicationThe Sciatic Nerve: Blocks, Injuries and Regeneration
EditorsDavid J. Fonseca, Joanne L. Martins
Place of PublicationHauppauge NY USA
PublisherNova Science Publishers
Chapter7
Pages157-174
Number of pages18
Edition1
ISBN (Print)9781611229165
Publication statusPublished - Apr 2011
Externally publishedYes

Keywords

  • Manganese-enhanced magnetic resonance imaging
  • Rat.
  • Retrograde tract tracing
  • Sciatic nerve

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