Dear Mrtrix experts,
I am trying to run the tckedit command with -maxlength option:
tckedit WB_tractogram.tck -include ROI1.nii.gz -include ROI2.nii.gz -maxlength 100 OUTPUT.tck -force
The problem is that this works with a whole brain tractogram (WB_sift.tck) file but not with another (WB_scil.tck).
When I run the previous command with “WB_sift.tck”, everything works fine: when I visualize the fibers, none of them exceeds the 100mm length.
However, when I run the same command with “WB_scil.tck”, I dont get any error but when I visualize the fibers, some of them are 130mm-long. So the maxlength option is not working.
I checked the difference between both tractograms and the main difference is the header information:
For WB_sift.tck (this is the one that works):
tckinfo WB_sift.tck
Tracks file: “/Users/adminuser/Desktop/ANE/Data/RAW_DATA/sub01/WB_sift.tck”
SIFT_mu: 0.0023769219808288207
act: sub_1/T1/5tt.nii
backtrack: 1
count: 1000000
crop_at_gmwmi: 1
downsample_factor: 3
fod_power: 0.25
init_threshold: 0.100000001
lmax: 6
max_angle: 45
max_dist: 200
max_num_attempts: 12530000
max_num_tracks: 12530000
max_seed_attempts: 5000
max_trials: 1000
method: iFOD2
min_dist: 2.29045677
mrtrix_version: 0.3.15-14-gfe1c8fff
output_step_size: 0.572614193
rk4: 0
samples_per_step: 4
sh_precomputed: 1
source: sub_1/DWI/FOD.mif
step_size: 0.572614193
stop_on_all_include: 0
threshold: 0.100000001
timestamp: 1488294706.9555587769
total_count: 10541097
unidirectional: 0
ROI: seed sub_1.mif
And for WB_scil.tck (the one not working):
tckinfo WB_sift.tck
Tracks file: “/Users/adminuser/Desktop/ANE/Data/RAW_DATA/sub01/WB_scil.tck”
count: 10541097
mrtrix_version: 0.3.15-14-gfe1c8fff
timestamp: 1490172345.8748898506
total_count: 10541097
Could this problem be related to the fact that there is no stepsize information in the header? How could I add info to the header of tck files? (mrconvert allows adding header info to .mif files but I dont think there is an analog for tck files)
Thank you and congratulations for your work. It is really helpful for a lot of people