How many gradients are required for tractography?


Can you tell me how many gradients are required for tractography?

Thank you so much for your help!

Hi @suhnyoung.jun,

Optimally, I reckon you’d want to aim for 45 ~ 60 gradient directions at a reasonably high b-value of e.g. 2500 s/mm^2 or higher. I haven’t seen results improve much, if at all, beyond that. That said, minimally, in our lab and collaborators’ experience, you can “get away” with 30 directions and b = 1000 s/mm^2, though results won’t be as good of course! For targeted tractography of well-known major structures, this might still be sufficient though.


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Thank you so much! It really helped a lot!! :slight_smile:


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No worries! :+1: