Dear FSL list (and Michael),
I have a question regarding the calibration of ASL images using a
voxel wise approach (M0a). In the BASIL guide the authors write
“Voxelwise calculation of M0a cannot be carried out using Asl_gui, use
the asl_calib tool directly”, unfortunately I could not find the
parameters in ASL_calib for the voxel-wise approach. Thus before I
used (in asl_calib) the perfusion image as input, the CSF as tissue
reference with the corresponding values, the structural image, the
M0-image and a CSF mask for the M0 image (I have no calibration image
for coil sensitive correction). I found the formula CBF= (perfusion
/Moa)*6000. Thus it mean that each voxel will be divided with its
specific M0 value (not one global value). Or is it enough to divide
the M0 image with lambda 0.9 and use a global M0-value?
Why do I need ASL_calib, because perfusion image is already created
during oxford_asl. It would be nice if someone could give me the exact
approach for the voxel wise approach (which parameters I need).
Best
Ralf
Ralf Veit PhD
Institute of Medical Psychology and Behavioral Neurobiology
Otfried-Müller str. 47
72076 Tübingen
phone: +49-7071-2987703
fax: +49-7071-295706
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