Double-diffusion-encoding (DDE) or double-wave-vector (DWV)
experiments show a signal behavior that is specific for restricted diffusion. Thus,
these experiments could provide more direct insight into tissue microstructure
than conventional experiments, especially when targeting axon diameters. In
this study, a previous DDE-based approach to estimate axon diameters is
extended (i) to be applicable without prior knowledge of the fiber
orientation, (ii) by considering a more complex tissue composition
including spherical cells and an unrestricted compartment to model glial cells
and extracellular space, and (iii) using the multiple correlation function
framework that provides a more accurate approximation of the MR signal.
