Optimizing Diffusion-Weighted MRI Using Electrostatic Repulsion
For optimal modeling of the tissue diffusion, the diffusion gradient directions need to be evenly distributed on a hemisphere (the signal attenuation in direction will be identical to directions ). This can be done using electrostatic repulsion of particles on a sphere . This method also allows for optimal multishell gradient distributions, where the shell weighting determines if the sub-shells are optimized () or the total number of directions is optimized () . Multiple shells are shown using points with different colors.
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