hello all,
I was wondering what is the best way to analyse the fiber tracking results when running the probabilistic tractography. I have two group (trainings and conrols). Probabilistic tractography were performed. The seed region was defined from the FSLVBM analysis. I want to test if the training affect the FA values in the fiber tracts connecting the seed region. I can't sure if my statistic processing was right as following:
1. performed probabilistic tractography from seed mask to all other voxels in the brain
2. tractography in individual subjects was threshold (at least 50 streamlines had passed out of 5000)
3. individual tracts was then binarized, transformed to standand space, summed across subjects to produce group probability maps
4.these group probabilistic maps were threshold (present in a minimum of one-third of subjects) and then both group probabilistic maps were combined together as a mask
5. voxel-by-voxel-based comparison of FA values were performed between groups. The mask produce from step 4 was used as explicit mask.
The validity of the step 4 is my major point want to verify .
Thank you for your help!
YX Li
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