Hi, on the fsl practical page, there is a step on preparing phase
difference map to a fieldmap in rad/sec with the following command
"fslmaths phasemap -sub 2048 -div 2048 -mul 3.14159 phase_rad -odt float".
When I look at the histogram of the intensity of the phasedif map, the
dicom file has a range of intensity from -4096 to 4092. In nifti format,
it's intensity range is 0 to 4094. May I ask if it is more accurate to
keep to 2048 or to substitute 2048 to 2047 in the above calculation?
Thanks
Siewmin
|