Dear SPMers:
My question is regarding usage “create(N)” (line # 570,716,188) in
spm_dicom_convert while spm_write_vol uses spm_create vol (line #196)
I’m using
spm_write_vol.m 800 2007-04-27 07:35:27Z
spm_dicom_convert.m 810 2007-05-07 14:38:54Z
MRI scanner: Siemens Allegra
Sequence: PASL(perfusion) weighted image in standard format(no mosaic).
After converting dicom files using spm_dicom_convert I typically fill in
with zeroes near the edges using combination of spm_vol and spm_write_vol
just to ensure I don’t have strange values around there.
I noticed intensity scaling in nifti headers (pinfo) changed during the
process of dicom->nitfti->fill in with zeroes using spm_write_vol.m. It
doesn’t effect image intensity with rescaling but I’m just wondering why
spm_write_vol.m modifies scaling constant. Does it have something to do the
difference between spm_create_vol vs create(N)?
It’s actually important for my purpose as I need to recover true image
intensity at the dicom level(before rescaling with nifti header), so if
scaling constants change during the operation I can’t recover the true
intensity.
Thanks in advance
Hedok.
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