FOD near the bone or air

Hi all MRtrix experts,

Are there any methods that can reduce the false-positive FOD lobes when voxels are near the bone or air regions?



Dear John,

Interesting question! To diagnose your problem, we need much more information:

  • What data are you using? (b-values, no. of directions, and spatial resolution)

  • How do you currently compute your FODs? (including preprocessing)

  • Screenshots of the erroneous FODs


Hi Ben,

Thanks for your reply!

I used HCP data (multi-shell data with b=1000/2000/3000 s/mm2, 288 dirs, and 1.25×1.25×1.25mm³ voxel size) to reconstruct FOD in the optic nerve region.
The data have already been well preprocessed, so I directly generate the FOD using msmt-csd algorithm.
Here is the visualization of the FODs in the optic nerve.