Using `PhaseEncodingDirection` field to distinguish sequences about bidscoin HOT 6 CLOSED

The reason is that PhaseEncodingDirection is not a DICOM tag, but something that dcm2niix produces. As far as I know, there is nothing in the DICOM header that can be used directly, so the best one can do is to use a different protocol name when scanning the inverted read-out scan

from bidscoin.

Perhaps, if the dcm2niix PhaseEncodingDirection logic is not too complicated I could implement it in dcm2niix2bids. It would be great if @neurolabusc could give some guidance here :-)

from bidscoin.

For Siemens, you read the CSA header. For GE, modrn releases use Rectilinear Phase Encode Reordering (0018,9034). You can find concrete validation datasets for both manufacturers, see dcm_qa_nih. The phase encoding polarity is not recorded in the DICOM images created by Philips.

from bidscoin.

Thanks, that's helpful. So CSA it is, what do you say, any chance of finding this info in (future) Siemens XA headers?

from bidscoin.

@marcelzwiers you can find Siemens XA30 enhanced as well as classic interoperability validation datasets. For XA you can read Phase EncodingDirection directly from the private tag 0021,111C or parse the CSA header (0021,1019). Beware, as this dataset demonstrates, that the a Siemens XA scanner can export the same scan with different tags depending on whether the enhanced or classic output is selected (e.g. ImageType vs ImageTypeText).

from bidscoin.

Should work now with commit e85d1f3

from bidscoin.