Dear all,
I have two MRI images, one T1 and one FLAIR image. I have been using
the "New Segment" tool on the T1 image, which gave me a _seg8.mat. I
then coregistered the T1 image on the FLAIR image using the coreg
function.
What I would like to do now is to be able to find corresponding
coordinates in MNI space of a voxel of the FLAIR image. I found the
spm_get_orig_coord function, which seems to do something quite
similar. However, the spm_get_orig_coord function only works with
_sn.mat and not with seg8.mat.
When trying to convert seg8.mat to a _sn.mat with the function
spm_prep2sn, I got the error:
??? Error using ==> spm_invdef
Too many voxels inside a tetrahedron
Error in ==> spm_prep2sn at 21
[Y1,Y2,Y3] = spm_invdef(Y1,Y2,Y3,VG(1).dim(1:3),eye(4),eye(4));
Does anyone have an idea how to solve that error so I can use
spm_get_orig_coord with a _seg8.mat ? Or is there an other way to
obtain voxel correspondance ?
The next step is to find the correspondance between the T1 coordinates
and the FLAIR coordinates. Since that should only be an Affine
transform, I guess I can use spm_get_orig_coord again but I would need
the transform matrix computed by the coreg function. Is there another
way to get it than the spm_matrix function, which would require to
relaunch the spm_coreg function ?
Thank you for your help and advice
Best regards,
Thomas
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