Rotationally-invariant mapping of scalar and orientational metrics of neuronal microstructure with diffusion MRI.
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ABSTRACT:
SUBMITTER: Novikov DS
PROVIDER: S-EPMC5949281 | biostudies-literature | 2018 Jul
REPOSITORIES: biostudies-literature
Publications
Rotationally-invariant mapping of scalar and orientational metrics of neuronal microstructure with diffusion MRI.
Novikov Dmitry S DS Veraart Jelle J Jelescu Ileana O IO Fieremans Els E
NeuroImage 20180312
We develop a general analytical and numerical framework for estimating intra- and extra-neurite water fractions and diffusion coefficients, as well as neurite orientational dispersion, in each imaging voxel. By employing a set of rotational invariants and their expansion in the powers of diffusion weighting, we analytically uncover the nontrivial topology of the parameter estimation landscape, showing that multiple branches of parameters describe the measurement almost equally well, with only on ...[more]
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