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shimming-toolbox / rf-shimming-7t

Repository for the paper "B1+ shimming in the cervical spinal cord at 7T"
https://shimming-toolbox.github.io/rf-shimming-7t/
MIT License
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TFL B1+ maps are not corrected for gradient non-linearity distortions #11

Closed jcohenadad closed 9 months ago

jcohenadad commented 9 months ago

This is problematic, because the values of the map are biased by the distortion (due to the Jacobian of the distortion field), hence it needs to be corrected.

image

Suggestion: apply off-line correction after finding the correct grad file for the gradients.

jcohenadad commented 9 months ago

After giving it additional thoughts, the quantitative map should not be corrected, because that correction would induce a bias in the corrected map. This is probably why the qMap output is not computed by Siemens.