Dear FSL list,
I got two different results with two slightly different command lines for extracting mean FA in the region of the right hippocampus based on the tbss skeleton. I'm wondering the reason of the differences and which one is right.
(1) fslmaths R_Hippocampus.nii.gz -thr 25 -mas mean_FA_skeleton_mask -bin RHippo_mask
fslmeants -i all_FA_skeletonised.nii.gz -m RHippo_mask -o meants_RHippo
(2)fslmaths R_Hippocampus.nii.gz -thr 25 -bin bin_RHippo_mask
fslmeants -i all_FA_skeletonised.nii.gz -m bin_RHippo_mask -o meants_RHipp_try
the first set of commands used mean_FA_skeleton_mask to mask the right hippocampus while the second set of commands whithout this. The result from the former was much larger than the latter. For example, 0.2645, 0.0072 for the same subject. I guess this was because the former had a much smaller denominator.
Would you give me some comments , and which command line in fslmaths is right?
Thanks in advance.
Best,
Qin
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