Axonal integrity predicts cortical reorganisation following cervical injury.
File(s)
Author(s)
Type
Journal Article
Abstract
BACKGROUND: Traumatic spinal cord injury (SCI) leads to disruption of axonal architecture and macroscopic tissue loss with impaired information flow between the brain and spinal cord-the presumed basis of ensuing clinical impairment. OBJECTIVE: The authors used a clinically viable, multimodal MRI protocol to quantify the axonal integrity of the cranial corticospinal tract (CST) and to establish how microstructural white matter changes in the CST are related to cross-sectional spinal cord area and cortical reorganisation of the sensorimotor system in subjects with traumatic SCI. METHODS: Nine volunteers with cervical injuries resulting in bilateral motor impairment and 14 control subjects were studied. The authors used diffusion tensor imaging to assess white matter integrity in the CST, T1-weighted imaging to measure cross-sectional spinal cord area and functional MRI to compare motor task-related brain activations. The relationships among microstructural, macrostructural and functional measures were assessed using regression analyses. Results Diffusion tensor imaging revealed significant differences in the CST of SCI subjects-compared with controls-in the pyramids, the internal capsule, the cerebral peduncle and the hand area. The microstructural white matter changes observed in the left pyramid predicted increased task-related responses in the left M1 leg area, while changes in the cerebral peduncle were predicted by reduced cord area. CONCLUSION: The observed microstructural changes suggest trauma-related axonal degeneration and demyelination, which are related to cortical motor reorganisation and macrostructure. The extent of these changes may reflect the plasticity of motor pathways associated with cortical reorganisation. This clinically viable multimodal imaging approach is therefore appropriate for monitoring degeneration of central pathways and the evaluation of treatments targeting axonal repair in SCI.
Date Issued
2012-04-06
Date Acceptance
2012-03-06
Citation
Journal of Neurology Neurosurgery and Psychiatry, 2012, 83 (6), pp.629-637
ISSN
1468-330X
Publisher
BMJ Publishing Group
Start Page
629
End Page
637
Journal / Book Title
Journal of Neurology Neurosurgery and Psychiatry
Volume
83
Issue
6
Copyright Statement
© 2012 The Authors. This is an open-access article distributed under the terms of the Creative Commons Attribution Non-commercial License, which permits use, distribution, and reproduction in any medium, providing the original work is properly cited, the use is non-commercial and is otherwise in compliance with the license. See: https://creativecommons.org/licenses/by-nc/2.0/ and https://creativecommons.org/licenses/by-nc/2.0/legalcode.
Identifier
http://www.ncbi.nlm.nih.gov/pubmed/22492214
PII: jnnp-2011-301875
Subjects
Adult
Aged
Axons
Case-Control Studies
Cerebral Cortex
Cervical Vertebrae
Demyelinating Diseases
Diffusion Tensor Imaging
Humans
Magnetic Resonance Imaging
Male
Middle Aged
Nerve Degeneration
Nerve Fibers, Myelinated
Neural Pathways
Neuroimaging
Psychomotor Performance
Pyramidal Tracts
Spinal Cord Injuries
Neurology & Neurosurgery
11 Medical And Health Sciences
17 Psychology And Cognitive Sciences
Publication Status
Published
Coverage Spatial
England