Neither reason really holds up. The surface vertex does not have a
volume associated with it. The extra vertices just look like smoothness
in the correction for multiple comparisons (which you will have
regardess), so there is no penalty. Bottom line is that you should stick
to fsaverage ico7
On 2/17/2020 5:35 AM, Marina Fernández wrote:
External Email - Use Caution
Hi Doug,
We thought it would be better to use 5th order icosahedron tesselation
for PET because the resolution of the volume is lower: If, for
thickness analysis, we carry the structural volumes with a resolution
of 1x1x1 to ico7 on the surface, with PET-volumes or connectivity maps
(resolution of 2x2x2 or 3x3x3) we thought it would be more appropriate
to use ico5 on the surface because in the surface transformation the
interpolation of the data is lower.
In addition the number of statistical comparisons is greatly reduced.
Regards,
Marina.
Marina.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Hi experts,
This is a question related to PetSurfer steps.
I would like to know if it is correct to sample the mgx volume onto the
surface of the average subject of my dataset (created with 5th order
icosahedron tesselation) instead of the fsaverage (created with 7th order
icosahedron tesselation) or if there is any problem in the next steps
following this procedure.
We would like to do that because the volume PET resolution is more
proportional to this number of vertex (10242). Do you think it is correct?
Best wishes,
Marina.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
You could do it, but I would just use fsaverage. I don't understand
what the relationship would be between the number of vertices on the
surface and the number of voxels in the PET volume or the rational for
using the 5th order ico
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