Hi Rodrigo,
The bvecs need to be specified in the frame of the imaging axes, which
in the typical case on a Siemen's scanner would mean that the bvecs as
stored in the DICOMs need to be rotated.
See Item 8 under Sample Datasets (and the Word document linked therein)
at the following website for details:
http://www.mccauslandcenter.sc.edu/mricro/mricron/dcm2nii.html
cheers,
-MH
On Thu, 2012-05-31 at 22:59 +0100, Rodrigo Perea wrote:
> So I am working with diffusion images and I was wondering if the head orientation will matter. My DWIs look as if the person was looking at the ceiling so about 45 degrees from the x-plane. DWIs were acquired like these and thus the bvecs should not change. However, after doing the DTIFIT on these images, the V1 is not clear with clear up-down left-right colors. Could this be because of the orientation of the head? Any help, any advice?
>
> Thanks,
> Rodrigo
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