Hi,
In Analyze you cannot store orientation information reliably (that's why
we prefer nifti). FSL has historically adopted the same conventions for
all Analyze images and these are the same as used in the avg152 images,
which can be described as "radiological" but that sometimes has different
interpretations by different people. See our FAQ for the precise
definition.
What I advise is to check the image by looking at it in FSLView, as this
will show you the labels such as L, R, A, P, S, I. If these are correct
then
everything is fine. If the acquisition is not axial then these will be
wrong
but check the example_func2standard image and see if that is correct.
If in doubt, run a test by doing something to the input image, inside
the brain,
such as manually editing some voxels to make them very dark which
you can then use to mark left and right and see if that is propagated
correctly.
All the best,
Mark
Vina Goghari wrote:
> Hello,
> I'm working on a dataset collected a while back, where all the data
> was stored as Analyze, but none of the orientation information was
> stored in .hdr file. However, the data was stored in radiological
> convention (right first then left). I was just wondering how FSL
> handles this data with out info in the header and whether I have to
> worry about the data being flipped. In the end the FSL post-stat maps
> appear to also be in radiological convention.
>
> I hope this makes sense!
>
> Thanks,
> Vina
>
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