Dmitry S. Novikov1, Jens H. Jensen1, Joseph A. Helpern1
1Radiology, NYU Medical Center, New York, NY, USA
Diffusion of water in tissues is strongly restricted on the cellular length scale. The consequence of such a restriction is a ubiquitous non-Gaussian shape of the diffusion-weighted imaging (DWI) signal. We demonstrate how a non-Gaussian shape of the DWI signal can originate solely due to the presence of cell membranes, with no diffusivity difference between the intra- and extra-cellular compartments. We find that the effective diffusivity acquires frequency dependence. We relate the cell membrane permeability and surface-to-volume ratio to experimentally relevant parameters, such as dispersive diffusivity and time-dependent kurtosis.