Notes from call on Nov 20

[KirstieJane]

All field maps all the time!

Current specification is only focused on B0 mapping. There are 4 techniques listed so far, but none that include B1+ or B1- maps.

👉 Update current specification to include other types of field maps. Work underway in the fieldmaps branch (see: 01-magnetic-resonance-imaging-data.md#b1-fieldmaps).

• A map is something with units - don't call something that has not yet been calculated into a map.
• Do we want to have multiple sufficies to separate the different sequences that can generate B1+ or B1- maps?
• If you want to scrape OpenNeuro for any of the acquisitions used to calculate field maps you'd hae to go into the metadat to know what sequences were used for them. That's the same for the B0 mapping files now. But the MAPS (could) have standard units and they could be compared.
• acq flag is available for the fieldmap folder - because it is free text then the user can put whatever they want in there.....but that means developers can't rely on the text in the acq flag.
  • We do currently restrict the use of acq for some of the qMRI sequences (see: 01-magnetic-resonance-imaging-data.md#allowedacq)
  • This opened up a big old 80/20 problem - it becomes much harder to search the metadata than just read the files.
  • We had a vote at the end of the call to 1) allow acq to be totally free and add in additional indexable_metadata to disambiguate certain sequences, 2) keep what we have and limit acq for some purposes or 3) sleep on it 💤 - we voted 3 😆
  • This doesn't solve the problem of what to do with certain field map sequences. So we need some example fieldmap data to start to build up specific indexable_metadata in the file names

NEXT MEETING: Monday 9 December at 8am PST / 11am EST / 4pm GMT / 5pm CET / 7pm TRT

These are not the greatest notes, but hopefully they help @ChristophePhillips extend the fieldmaps branch with some clearer usecases 💖