Advanced Techniques for Imaging the Human Spinal Cord: Review of Literature

Despite the high sensitivity of magnetic resonance imaging (MRI) in detecting a wide spectrum of various pathological processes, the specificity of the method to differentiate among these pathologies and its ability to predict clinical outcomes has been rather below initial expectations. The main problem arises from the fact that most of the pathologies of the spinal cord manifest with a rather nonspecific increase of water protons, reflecting local oedema or gliosis. This is a common finding in most myelopathies, which does not allow a further differential diagnostic distinction in most cases. The use of contrast media improved the specificity of the method; however, it is still challenging to differentiate types of myelopathies. Advanced imaging methodologies such as functional MRI (fMRI), diffusion-weighted and -tensor imaging (DWI/DTI), Magnetic Resonance Spectroscopy (MRS) have been used in the evaluation of neurologic diseases in the brain and have gained increased acceptance among the clinicians for improving the specificity of MR technology and for their ability to better correlate with functional disabilities and clinical symptoms thus providing predictive information about potential outcome. Preliminary results show that, quantitative parameters extracted by these techniques from the spinal cord can provide surrogate markers of disability for determining prognosis as well. In this review, we focus on implementing advanced neuroimaging methodologies (DWI/DTI, fMRI and MRS) in imaging of the human spinal cord for better clinical assessment. Additionally, we review the recent imaging literature advances in this topics and their clinical applications.