fixel-based analysis in stroke patients

Dear MRtrix experts,

I’m currently analyzing a dataset of stroke patients with 18 strokes and 17 controls. There are 5 patients with right-hemispheric and 13 with left-hemispheric stroke lesions. The main focus is on comparing the affected to the unaffected hemisphere (and the correlation with different behavioral measures). I am wondering if fixel-based analysis with statistical analysis of FD, FC, and FDC is possible in this cohort. How do I take the different sides of stroke lesions into account? Is it possible to flip the dwi images beforehand?

Thank you very much for your help,

Sabeth

Dear Stephanie,

Just my humble opinion, and also not a real expert ;-).
The biggest problem in stroke patients is the huge anatomical variations you will have in your images.
If you only want to compare healthy sides this is less of a problem, and mirroring your images (after FOD calculation seems handiest to me, as you don’t have to adjust your bvecs) will be quite feasible). However, If you want to make a comparison of all affected patients, the anatomical variation in your dataset might dominate your result.
Another strategy might be tracking some fibres and calculating FD, FC and FDC of these fibres and compare these between patients and hemispheres

For taking into account the effect of hemisphere, you might add this as a covariate in your analysis.

I hope this was of any help to you.

Cheers,
Jeroen