MRtrix3 / mrtrix3

MRtrix3 provides a set of tools to perform various advanced diffusion MRI analyses, including constrained spherical deconvolution (CSD), probabilistic tractography, track-density imaging, and apparent fibre density
http://www.mrtrix.org
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New command: dirrotate #2943

Closed Lestropie closed 2 months ago

Lestropie commented 4 months ago

Closes #2749.

Have had a lot of issues locally with getting DWI protocols to execute reliably without yielding scanner hardware complaints or outright termination. One of many contributing factors was the presence of volumes for which the direction of diffusion sensitisation aligns very closely with one of the scanner physical axes. This maximises power amplifier & cooling load, and risks exceeding peak amplitude capability once gradient pre-emphasis is added.

This command finds (via brute force) an axis & angle of rotation for which its application results in the minimum of maximum cosines across the direction set. By integrating this into my scheme generation script, I was able to reduce the maximal requested gradient amplitude from 0.995 to 0.980. There is zero consequence to other aspects of the scheme such as nearest neighbour angles and SH transform condition number.