Hi.
I'm trying to run an ASL analysis on my data. I have pcASL
control-tag data that for the most part are getting run through the
analysis without problems. However, there seems to be some
difficulties with the calibration.
I'm running the command as root in csh:
oxford_asl -i $INPUT/analysis/diffdata -o
$INPUT/analysis/KMI_data --tis 3.6 --bolus 1.8 --bat 1.8 --casl \
--t1b 1.6 --alpha 0.98 --artoff --fixbolus \
--infert1 -s $ANATFOLDER/anat_roi_brain
--report \
--regfrom $INPUT/PCASLmean_brain --spatial \
-c $INPUT/M0.nii.gz --tr 12
the error is such:
Number of voxels is:81920
Number of repeats in data is:70
Outputting ASL data mean at each TI
Done.
OXFORD_ASL - running
Creating output directory
Saving results in natve (ASL aquisition) space to
ASL/analysis/KMI_data/native_space
Saving results in structural space to
ASL/analysis/KMI_data/struct_space
Pre-processing
Creating mask
Performing registration
ASL_REG
Input file is: /ASL/PCASLmean_brain
Running FLIRT
Tidying up
ASL_REG - Done.
Segmenting the structural image
Calculating M0a - calling ASL_CALIB
ASL_CALIB
Tissue reference is: csf
Image Exception : #22 :: ERROR: Could not open image
/tmp/fsl_SsEGkZ_asl_calib/seg_bias
libc++abi.dylib: terminating with uncaught exception of type
RBD_COMMON::BaseException
/usr/local/fsl/bin/asl_calib: line 568: 58142 Abort trap:
6 ${FSLDIR}/bin/applywarp --ref=$calib
--in=$temp_calib/seg_bias --out=$temp_calib/biasfield
--premat=$temp_calib/high2low.mat --super --interp=spline
--superlevel=4
Cannot open volume /tmp/fsl_SsEGkZ_asl_calib/biasfield for
reading!
Image Exception : #22 :: ERROR: Could not open image
/tmp/fsl_SsEGkZ_asl_calib/sens
libc++abi.dylib: terminating with uncaught exception of type
RBD_COMMON::BaseException
/usr/local/fsl/bin/asl_calib: line 689: 58150 Abort trap:
6 fslmaths $temp_calib/calib -div $temp_calib/sens
$temp_calib/calib
M0:874.58000000000000000000
ASL_calib - DONE.
Best regards,
Athanasia Mowinckel