Whole brain tractogram

Dear All,
I have ran the anatomically contrained tractography on my DTI data with bvalue =1000 and bvecs= 56 directions. where I get the attached SIFT corrected tractogram but I am not sure it is correct or not.
So plaese have a look and let me know your point of views.


Hi Neeraj,

The data look basically as expected:

  • Streamlines stringently constrained within WM and SGM due to the use of ACT.

  • Spatial distribution of streamlines density (gauged by the amount of “empty space” in between the streamlines) is approximately equal across the white matter; this is not explicitly a constraint in SIFT, but tends to be what the FOD data suggest, and also makes sense from a physical perspective (if one can fit a certain density of fibres within a given volume of white matter in one area of the brain, why would the density of fibres be grossly smaller or larger than this elsewhere in the WM?).

The low-ish b-value means that the interpretation of FOD amplitude (and concomitantly streamline count post-SIFT) can’t be interpreted as being proportional to intra-cellular volume / cross-sectional area with confidence… but applying SIFT nevertheless is likely still preferable to omitting that step.


Thanks Smith for your response.
I have created a dentato-rubro-thalamo-cortical tract using the Same data but avoiding the ACT as I was not getting any streamlines after applying the ACT (I am not sure what is the region).
Now I want to calculate the fiber count reaching from dentate to thalamus. Could you please guide me How I can achieve this Goal.
Please guide me in further analysis.
Attached an image of the tract

Once you have created a track file containing only those streamlines of interest, examining the header of the track file using the tckinfo command will tell you how many streamlines are present in that file.