Dear Chantal,
Most likely what you are describing is a result of how DARTEL moves
the data to MNI space, and is not something to be concerned about.
See a number of previous posts (try searching for "functional DARTEL"
or something similar). For example:
https://www.jiscmail.ac.uk/cgi-bin/wa.exe?A2=ind0908&L=SPM&P=R895
or
https://www.jiscmail.ac.uk/cgi-bin/webadmin?A2=ind0910&L=SPM&P=R3826&1=SPM
Hope this helps!
Jonathan
On Wed, May 18, 2011 at 10:36 AM, Chantal Roggeman
<[log in to unmask]> wrote:
> Dear SPMmers,
>
> I have a problem with Dartel - normalise to MNI space. It runs all right, but my images are distorted after the Dartel normalisation.
>
> For the whole preprocessing, I followed basically the manual: realignment (estimate and reslice), coregistration (estimate), New Segment, run Dartel (create Template), then Dartel normalize to MNI space.
>
> Everything ran without errors, but my functional images are distorted after the last step. The original and realigned images were all right, so it must happen in a later stage. It looks like some part of the brain is stretched out. The distortion looks different in different sessions, but is the same for all images in the same session.
>
> Is this a known problem? Does anybody know why it happens and how I can avoid it? Since everything ran smoothly without errors, I have no idea what the problem could be...
>
> thanks a lot!
> Chantal
>
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