if your scanner is SIEMENS and you use the Diffusion II toolbox to
estimate the tensors, then you should be fine. This toolbox explicitly
assumes the gradient vectors to be encoded in "world" space, which is
what you seem to describe.
Otherwise, you can also use the world-to-voxel mapping to reorient your
gradients. To reorient the tensor images, you would have to do this
voxelwise for 6 images simultaneously. This is quite time consuming.
Am Montag, den 23.03.2009, 16:41 +0100 schrieb Peter Erhard:
> Hi all DTI experts,
> I am obviously no expert.
> We acquired data with a DTI sequence, but did align our slices with AC-PC,
> which in all cases was not exactly transversal.
> Now I checked the DTI gradients and found out, that these are not being
> rotated when rotating the imaging slice plane.
> Is there a way to rotate the tensors, or gradient values to correct for
> this problem?
> Can this be done in one of the DTI toolboxes?
> All advices are welcome.
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