Hi - yes you do need to adjust your bvecs before feeding them into
DTIfit or bedpostx.
Cheers.
On 22 May 2009, at 09:57, <ERIK> <O'Hanlon> wrote:
> Dear FSL experts,
>
> We are just starting to acquire DTI data in 60 directions on a
> Philips 3T system. The images
> are acquired in the axial plane but are angled by about 20 degrees
> to remove the nasal
> cavity artefacts as much as possible and also to capture the entire
> cerebellum with out
> adding more slices (and hence increasing time which is already at 22
> mins). Will this
> angulation cause a problem during the analysis and do I need to
> correct for this before I
> process the data? If so how do I go about changing the bvec file to
> reflect the angle? and at
> what stage in the pipeline (initially , after eddy correction, after
> DTI fit , before bedpost?).
>
> Thanking you in advance and any advice would be much appreciated.
>
> Erik
>
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Stephen M. Smith, Professor of Biomedical Engineering
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FMRIB, JR Hospital, Headington, Oxford OX3 9DU, UK
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