Magnetization Transfer and Diffusion-Weighted Magnetic Resonance Imaging in Multiple Sclerosis and Other White Matter Diseases

Abstract

In white matter diseases, 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 these lesions. Other quantitative MR techniques have the potential to overcome this limitation. Among these techniques, MR spectroscopy (MRS), magnetization transfer imaging (MTI), and diffusion-weighted imaging (DWI) are those which have been most extensively applied to the assessment of white matter diseases. Since the role of MRS in the assessment of white matter diseases is discussed elsewhere in this book, the present review will summarize the major contributions given by MTI and DWI for the understanding of the evolution of white matter diseases, with a special focus on multiple sclerosis (MS). The application of these two quantitative MR techniques to the study of MS is dramatically changing our understanding of how MS causes irreversible deficits and can serve as an useful model to be applied to other white matter diseases.