Demyelinating plaques, as seen in multiple sclerosis,  cause destruction of white matter fibers which is manifested on diffusion tensor imaging (DTI) as increased diffusivity of water molecules. This can be demonstrated by comparing fractional anisotropy (FA) and ADC values at the plaque site, normal appearing white matter (which may be affected but to less degree) and far normal appearing white matter. Tractography can illustrate the affected white matter tract.

FA and ADC values can be used to assess progress on follow-up.