I would like to apply FSL’s
topup to a dMRI dataset that I have from a Siemens Prisma 3T scanner. In order to figure out waht my
datain parameter values should be. Supposedly I was given an AP and PA acqusition, together with a pair of fieldmap volumes, which I believe are phase-encoding polarity volumes.
My DICOM metadata shows that the
-j (AP) and
j (P). Is there a way to know what these correspond to for the
Additionally, I am unable to find the the EPI factor value in the metadata. Attached are the anonymized JSON sidecar data obtained when converting the DICOM data into BIDS format. Is there a particular name for the EPI factor that I ignore for this type of scanner?
Here, despite being a thread about Philips data,
they say "(…) “EchoTrainLength”, which I believe corresponds to (EPI factor + 1) after taking into account acceleration.”
In my dMRI data “MultibandAccelerationFactor” is 4, but I am not sure how that affects the EPI factor computation.
Finally, I am not very familiar with the possibilities of
topup or susceptibility correction details, so I am not sure if there are ways in which the PE polarity volumes can be otherwise used together with the AP/PA dMRI data. Pointers are welcome.
sub-0001_acq-dir99_dir-ap_dwi_anon.json.txt (17.4 KB)
sub-0001_acq-dir99_dir-ap_run-01_epi_anon.json.txt (6.6 KB)
sub-0001_acq-dir99_dir-pa_dwi_anon.json.txt (17.4 KB)
sub-0001_acq-dir99_dir-pa_run-02_epi_anon.json.txt (6.6 KB)