Diffusion Tensor Imaging of the Spinal Cord: Insights From Animal and Human Studies

1Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, WI 2Department of Biomedical Engineering, Marquette University, Milwaukee, WI 3Department of Radiology, Medical College of Wisconsin, Milwaukee, WI.
Neurosurgery (Impact Factor: 3.62). 09/2013; 74(1). DOI: 10.1227/NEU.0000000000000171
Source: PubMed


Diffusion tensor imaging (DTI) provides a measure of the directional diffusion of water molecules in tissues. The measurement of DTI indices within the spinal cord provides a quantitative assessment of neural damage in various spinal cord pathologies. DTI studies in animal models of spinal cord injury indicate that DTI is a reliable imaging technique with important histological and functional correlates. These studies demonstrate that DTI is a non-invasive marker of microstructural change within the spinal cord. In human studies, spinal cord DTI shows definite changes in subjects with acute and chronic spinal cord injury, as well as cervical spondylotic myelopathy. Interestingly, changes in DTI indices are visualized in regions of the cord, which appear normal on conventional MRI and are remote from the site of cord compression. Spinal cord DTI provides data that can help us understand underlying microstructural changes within the cord, and assist in prognostication and planning of therapies. In this article, we review the use of DTI to investigate spinal cord pathology in animals and humans, and describe advances in this technique that establish DTI as a promising biomarker for spinal cord disorders.

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