S5: Distortion Correction

Susceptibility artifact correction for spinal cord fMRI.

Purpose

S5 corrects geometric distortions caused by magnetic susceptibility differences near the spinal cord.

Algorithm

1. Fieldmap Processing - Prepare fieldmaps if available
2. Unwarping - Apply distortion correction
3. Fallback Methods - Use SyN registration if no fieldmap

Approaches

• Fieldmap-based correction (preferred)
• Reverse phase-encode (TOPUP)
• Fieldmap-less registration

Implementation in progress