Diffusion MRI is a powerful tool to characterize tissue micro structure and to identify and differentiate disease processes. Diffusion is a process describing the motion of water molecules in biological tissue. Diffusion MRI makes use of sequences developed to reveal differences in tissue characteristices with the parameters mean diffusivity D and the anisotropy FA.

Diffusion MR imaging has demonstrated its value for the early detection of stroke. Diffusion imaging also promises to further our understanding of brain disorders and abnormalities such as tumors, multiple sclerosis, and schizophrenia.

Advanced mathematical algorithms can be applied to reveal the connectivity of white matter fibres from multi-directional diffusion tensor measurements. Since the diffusion across fibres is restricted and almost free along the fibres, this property can be used to compute three-dimensional representations of fibre structures. The image below is an example to reveal the directional characteristics of the corpus callosum.