Dear experts, I read some previous answers about the thresholding of the paths obtained after tracula process, but I am not completely sure I had the right answer. I will need to get an roi from a path for example the cortico-spinal tract that will be consistent amongst patients. I will further use this roi to calculate the lesion volume (my subjects are patients with MS) within a specific path. My question is: is the path.pd.nii.gz file already threshold or should I threshold it to a specific value? If I use the same threshold for each subject for example at 10% of the maximum value, will I obtain an ROI that is consistent among subjects or is is possible that I would get a very thin CST in some subjects, or a very wide cst for example? Thanks for your help Celine