Compute contrast agent concentration time-course from signal time-course for each voxel and for spinal muscle (reference region)
1. Compute actual (B1-corrected) flip angle at voxel using α=B1∗αnom .
2. Normalize signal time course by mean signal prior to bolus injection
3. Compute T1 time-course using equation
T1(t)=−TR/ln(A−SR(t)cosαA−SR(t)) , where
A=1−e−TR/T1,01 − e−TR/T1,0cosα and
T1,0 is the baseline T1, obtained from the previously generated T1 map (step 3)
4. Estimate contrast agent concentration time-course using equation
C(t)=(T1(t)1−T1,01)/RGd , where
RGd=4.6/s⋅mM (check for your specific contrast agent)