Double
diffusion encoding experiments with two weighting periods applied
successively in the same acquisition offer access to microscopic
tissue properties. Rotationally invariant measures of the so-called
microscopic diffusion anisotropy as a marker for cell or compartment
shape have reliably been determined in brain white matter. In this
study, it is demonstrated that microscopic diffusion anisotropy can also
be detected in cortical gray matter in vivo and measures of it can be
determined extending first evidences presented recently. However, an
inversion recovery pulse is required to null white matter signals and
avoid partial volume effects.
