Hi everyone,
I’m using diffusion MRI data that has been preprocessed with Micapipe and I couldn’t figure out whether in the case of multi-shell data all shells are being used when the diffusion tensor model is fitted, or whether only one shell is selected for this step. In the paper it only says “A diffusion tensor model (Basser et al., 1994) is then fitted to the corrected DWI and the fractional anisotropy and mean diffusivity images are computed (Veraart et al., 2013).” and I didn’t see any step in the code that selects a shell but maybe someone could confirm this?
I’m wondering this because I’ve seen in some papers that only one shell was picked because DTI is not a good model for multi-shell data and especially for higher b-values the assumption of Gaussian diffusion doesn’t hold.
Thanks in advance!
Tanja