Diffusion tensor imaging in the human spinal cord: development, limitations, and clinical applications

Diffusion tensor imaging (DTI) is currently the only non-invasive in vivo assessment of white matter tract integrity. Capitalizing on the diffusion properties of water within an axon, DTI enables the visualization of tissue structure at a microscopic scale. Furthermore, measurements of anisotropy and diffusivity enable the detection of subtle details of the effects of injury that cannot be detected using conventional magnetic resonance techniques. Recently, DTI has been applied to the spinal cord, and results have demonstrated it to be a valuable tool for assessing the extent of white matter damage in numerous spinal cord-related conditions including multiple sclerosis, spinal cord injury, amyotrophic lateral sclerosis, myelitis, and spinal cord tumors. The purpose of this review is to discuss the technical limitations of the imaging method within the spinal cord, review possible solutions, and highlight the current uses and the potential clinical application of this technique.