IntendedFor with fieldmaps for all EPIs

[sajjad]

Hi All,

After running heudiconv, I did not add IntendedFor in my fieldmap JSONs, so at the beginning of fMRIPrep (which finished successfully) I got:
“None of the available B0 fieldmaps are associated to </data/sub-01/ses-01/func/sub-01_ses-01_task-physoc_run-1_bold.nii.gz>”
and
“Setting-up fieldmap “auto_00000” (EstimatorType.PEPOLAR) with <sub-01_ses-01_acq-opphase_dir-AP_epi.nii.gz, sub-01_ses-01_acq-opphase_dir-PA_epi.nii.gz>”

My question is 1) are there any issues with continuing with no IntendedFor, as I want to use my AP and PA fieldmaps to correct all EPIs and I don’t need to point to specific ones?

2. If, for some reason, I want to point my fieldmaps to a specific EPI, should I add IntendedFor under both sub-01_ses-01_acq-opphase_dir-AP_epi.json and sub-01_ses-01_acq-opphase_dir-PA_epi.json?

Thanks a lot for the help!

[Steven]

@sajjad

1. are there any issues with continuing with no IntendedFor, as I want to use my AP and PA fieldmaps to correct all EPIs and I don’t need to point to specific ones?

Yes, you need the IntendedFor field, and should explicitly state which EPIs each fmap is associated with, even if it all of them.

@sajjad

If, for some reason, I want to point my fieldmaps to a specific EPI, should I add IntendedFor under both sub-01_ses-01_acq-opphase_dir-AP_epi.json and sub-01_ses-01_acq-opphase_dir-PA_epi.json?

Yes, the IntendedFor field should be in each json file corresponding to an fmap you want to use.

[sajjad]

Great, thanks for the help!