Modeling diffusion of intracellular metabolites in the mouse brain up to very high diffusion-weighting: Diffusion in long fibers (almost) accounts for non-monoexponential attenuation.

ABSTRACT:

Purpose

To investigate how intracellular metabolites diffusion measured in vivo up to very high q/b in the mouse brain can be explained in terms of simple geometries.

Methods

10 mice were scanned using our new STE-LASER sequence, at 11.7 Tesla (T), up to q_max = 1 μm^-1 at diffusion time t_d = 63.2 ms, corresponding to b_max = 60 ms/µm². We model cell fibers as randomly oriented cylinders, with radius a and intracellular diffusivity Dintracyl, and fit experimental data as a function of q to estimate Dintracyl and a.

Results

Randomly oriented cylinders account well for measured attenuation, giving fiber radii and Dintracyl in the expected ranges (0.5-1.5 µm and 0.30-0.45 µm²/ms, respectively). The only exception is N-a

SUBMITTER: Palombo M 

PROVIDER: S-EPMC5326576 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature