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Hello all,

I have a series of fMRI images collected with a spiral in-out sequence. They are .nii files, which is the format I receive them in Because of the nature of the spiral in-out acquisition, I don't have dicom files to convert to nifti, but we have some sort of in-house conversion process. I am afraid I am foggy on those details, as I have more or less simply been given the data set to work with.

When loaded into fslview, all images are displayed the same way. Also, the x,y,z coordinates appear to be correct, in that +X goes to the right, +Y goes anterior, and +Z goes superior.

However, the labels in fslview are not correct for most images. I am referring to the L/R/A/P/S/I labels for orientation. In this case, for example, the 'L' label is actually positioned on the anterior of the brain.

I need to know how I can fix this. I read the wiki entry on orientation, but i am not sure I followed it completly.

 I would appreciate any specific help people can give on what procedure I should use to correct the labels. I am of course very concerned about maintaining L/R orientation.

I do have a couple of images with the labels correct in fslview. For reference, I used fslorient to get qform and sform for the correctly labelled and incorrectly labelled images. The sform is the same, qform is different.

Correctly labelled image:
sform: -3.4375 0 0 0 0 3.4375 0 0 0 0 5 0 0 0 0 1
qform: -3.4375 0 0 111.6 0 -3.4375 0 139.2 0 0 5 -48.3 0 0 0 1

incorrectly labelled image:
sform: -3.4375 0 0 0 0 3.4375 0 0 0 0 5 0 0 0 0 1
qform: 1.17661e-07 3.4375 0 -109.1 -3.4375 1.17661e-07 -0 137.9 -0 0 5 -77 0 0 0 1

Thanks a lot all.
Colin