Hi all,
I've been trying to construct a ROI of putamen that includes all voxels that
have a 25% probability of belonging to the putamen according to the Harvard-
Oxford subcortical atlas
I've used the following command to get this ROI:
fslmaths /fsl/data/atlases/HarvardOxford/HarvardOxford-sub-maxprob-thr25-
1mm.nii.gz -uthr 51 -thr 51-bin 25_prob_r_putamen
This works fine, however, when overlaying the generated mask on the 1mm
MNI Template brain in fslview and having the atlas switched on, I noticed that
some voxels just 1mm outside of the mask (i.e. where the mask is zero) had a
probability of belonging to the right putamen that was substantially higher
than 25%, I've seen values up to 47%.
I would have expected that everyting outside the mask should have values for
right putamen that are below 25%. Does anyone have an idea what could
have gone wrong here?
Thank you very much,
Gerhard
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