Hi FSL Experts,
I used "dcm2nii" to convert a set of PAR/REC (v3) DTI data acquired from 3T Philips
Gyroscan at the F.M. Kirby Research Center to NIFTI format. dcm2nii did not
automatically output the bvecs and bvals data, so I use a free matlab script
(dti_gradient_table_creator.m) to create the gradient direction data.
Suggested by the previous threads, I also eliminate the last entry of the gradient table
[100,100,100], which left me with 33 entry (b0+32 directions). I also used fslroi to
eliminate the last volume which said to be a diffusion traced image.
However, when I run dtifit, I got the following error message:
ysheu$ dtifit -k data.nii.gz -o dti -m nodif_brain_mask.nii.gz -r bvecs -b bvals
"terminate called after throwing an instance of 'NEWMAT::IndexException'
Abort trap"
I really don't know what went wrong. The number of volumes matched to the bvecs and
bvals, so it should not be the problem. Is there something wrong with my DTI data?
Any input is appreciated.
Thanks.
Yi-Shin
PS. I attached my bvecs and bvals and below is the info related to my data.nii.gz 4D DTI
image:
ysheu$ fslinfo data.nii.gz
data_type FLOAT32
dim1 256
dim2 256
dim3 60
dim4 33
datatype 16
pixdim1 0.8281250000
pixdim2 0.8281250000
pixdim3 2.2000000477
pixdim4 6.0850000381
cal_max 0.0000
cal_min 0.0000
file_type NIFTI-1+
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