Hi,
don't bedpost MDDW data with less than about 30 directions! See previous posts on this.
For the bvecs, they will depend on whether [xyz] or [qrs] coordinates are used. The former are fixed to the magnet, the latter to the angulation. If you use the former but angulate your slices the bvecs have to be adjusted. Jolindas MRIconvert (http://lcni.uoregon.edu/~jolinda/MRIConvert/) will extract proper (unnormalized) bvecs for you.
Cheers-
Andreas
________________________________
Von: FSL - FMRIB's Software Library im Auftrag von Robert Terwilliger
Gesendet: Do 27.07.2006 23:29
An: [log in to unmask]
Betreff: [FSL] Siemens Allegra MDDW6/12
Hi,
I have run bedpost on a DTI set acquired with the
stock MDDW12 sequence provided by Siemens.
I created the bvecs, bvals and other files according
to instructions. The resulting images, however,
suggest a problem with my bvecs file.
Has someone successfully run bedpost using the Siemens
protocols (6 and/or 12 encodings)? If so, could you
send me the bvecs file(s) that you used?
Regards,
Robert Terwilliger
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