Hi
You can use probtrackx for deterministic tracking, e.g. if you use orientation distributions that have only one sample. You will need to convert your V1 orientation file to theta/phi angles.
Note however that probtrackx is not designed to do deterministic tractography. Using probtrackx this way is sub-optimal for two reasons: (1) The results are stored as spatial histogram counts rather than individual streamlines; and (2) probtrackx performs "probabilistic interpolation".
If you still want to use probtrackx, then you can use fslroi/fslmaths to transform V1 to theta/phi by inverting these transformations:
V1x = sin(theta)cos(phi)
V1y = sin(theta)sin(phi)
V1z=cos(theta)
Cheers
Saad
On 20 Apr 2013, at 09:29, Gabor Perlaki <[log in to unmask]> wrote:
> Dear all,
>
> Can I use streamline tractography on diffusion data generated with FSL's dtifit or is it any program capable to use
>
> <basename>_V1 and <basename>_FA data for streamline tractography.
>
>
> Thanks,
> Gabor
>
--
Saad Jbabdi
University of Oxford, FMRIB Centre
JR Hospital, Headington, OX3 9DU, UK
(+44)1865-222466 (fax 717)
www.ndcn.ox.ac.uk/team/researchers/saad-jbabdi
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