Dear FSL experts,
I was looking at the asl_calib code and I was wondering if anyone could explain me where does the pcsf=1.15 come from? Because in that article the pcwm and pcgm are mentioned but the pccsf isn't.
"# partition coeffs
# based on Herscovitch and Raichle 1985
pccsf=1.15 # a blood water density of 0.87
pcwm=0.82
pcgm=0.98"
I also don't quite get this normalization process because this way, the equilibrium M0 blood is lower than M0_ref and I think it should be the other way around. Can anyone explain me this?
"# use equation to get the M0 value that is needed
#echo "$Moval $te $T2r $cgain $T2bl"
Moval=`echo "$Moval / e(- $te / $T2r )" | bc -l` # T2 correction for M0 reference
#echo $Moval
Moval=`echo "scale=2;$Moval*$cgain / $pc" | bc` # this is M0 blood (at TE=0)
#echo $Moval
Moval=`echo "$Moval * e(- $te / $T2b )" | bc -l` # get M0 blood at TE used
echo "M0:$Moval""
All the best,
Gonçalo
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