In-vivo tissue characterization of multiple sclerosis and other white matter diseases using magnetic resonance based techniques.

In several white matter diseases of the central nervous system (CNS), and in particular in multiple sclerosis (MS), conventional magnetic resonance imaging (MRI) has proved to be sensitive for detecting lesions and their changes over time. However, conventional MRI is not able to characterize and quantify the tissue damage within and outside such lesions. Other quantitative MR techniques, including proton MR spectroscopy (1H-MRS), magnetization transfer MRI (MT-MRI) and diffusion-weighted MRI (DW-MRI) have the potential to overcome this limitation and, as a consequence, to provide additional information about the nature and the extent of tissue damage, which would be inevitably lost when only conventional MRI is obtained. Metrics derived from MT- and DW-MRI can quantify the structural changes occurring within and outside lesions visible on conventional MRI scans. 1H-MRS could add information on the biochemical nature of such changes. The application of these MR techniques to the study of MS is increasing dramatically our understanding of how MS causes irreversible disability and it is likely to provide useful insights into the pathophysiology of other diseases of the CNS in the near future.