Hi Kent,
For what it's worth, when I reconstruct our Siemens Magnetom Trio DICOM
fieldmap images using MRIcron, I get 2 magnitude images and one phase map.
The phase map is scaled with slope of 2 and an intercept of -4096. To
convert that to radians per sec, I use the following command:
fslmaths fieldmapping64s006a201.nii.gz -mul 3.14159 -div 4096 -div .00246
fieldmap.nii.gz
fieldmapping64s006a201.nii.gz is the name of the phase map.
Multiplying the phase map by 3.14159 and dividing by 4096 converts the
image to -pi to pi. Dividing again by .00246 converts to
radians/sec. .00246 is the TE difference, in seconds. In my case, TE1 =
2.84 ms and TE2 = 5.3 ms, thus TE diff = 2.46 ms, or .00246 s.
fieldmap.nii.gz is the properly scaled fieldmap that is output by this
command. It's the one that I use for B0 unwarping in FEAT.
Hope this is helpful! Ignore if this isn't what you were looking for. :)
Cheers,
Heather
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