Dear Saad and others!
We notice a strange behavior in our probtrackx result of FSL 4.1.2.
We used a seed sphere in the corpus callosum and applied another
sphere about 3 cm lateral in the splenium as both a waypoint and a
termination mask.
My understanding is that we only should get those regions where fibers
start form the seed and travel to the termination/waypoint.
The resulting fdt_path however shows areas in both hemispheres and
largely behind the termination mask, similar to the use of NO
termination/waypoint.
I read about the minor bugfix in version 4.1.3. about the termination
mask behavior.
We would like to know if the waytotal counting actually only contains
the right numbers or if it is including the wrong superfluous paths.
However the waytotal calculation gives me 33 seedvoxels* 5000 samples
= 165000 for without waypoint
and fslstats fdt_path -M = 2789. 2789 * 33 = 92037 for the use with
waypoint/termination.
So it seems it somewhat respects the waypoint/termination. But does it
respect both or only the waypoint mask but not the termination?
As on our server are currently about 4 studies running I would not
update when not absolutely necessary in this particulary case!
Thanks so much for your help!
Best, Markus
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