Troubleshooting Distrotion correction and Co-registration stpes

[wageeshaWLW]

I am encountering a common preprocessing issue where the co-registration between my functional (EPI) and anatomical (T_1w) data is failing. Despite attempting Susceptibility Distortion Correction (SDC) with field maps (fmaps), the alignment remains incorrect. My current pipeline uses a 6 Degrees of Freedom (DOF) transformation for this step. I suspect that increasing the transformation to 12 DOF might resolve the misalignment, and I am also interested in exploring options for performing fieldmap-less distortion correction.

During the SDC process, the following files were also generated.

sub-003_ses-001_fmapid-auto00000_desc-preproc_fieldmap.json
sub-003_ses-001_fmapid-auto00000_desc-preproc_fieldmap.nii.gz
sub-003_ses-001_fmapid-auto00000_desc-epi_fieldmap.nii.gz
sub-003_ses-001_fmapid-auto00000_desc-coeff_fieldmap.nii.gz

And here I attached the corresponding report of one subject in the dataset.

sub-003.html.zip