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Hello FreeSurfer Community!

I previously asked a question about volume quantification using an external atlas (in fact, there are 20 brain masks corresponding to the regions of interest). I managed to perform the quantification with the following commands and would like to know if everything is correct:

Use mri_vol2vol to upsample to 1mm:


/usr/local/freesurfer/subjects# mri_vol2vol --mov '/home/pedro/Downloads/Sallet_ROIs/Cluster1_L.nii'  --targ '/usr/local/fsl/data/standard/MNI152_T1_1mm_brain.nii.gz' --regheader --o Cluster1_L_1mm.nii --interp nearest


Use mri_vol2surf to create surface in XXX space:

/usr/local/freesurfer/subjects# mri_vol2surf --mov Cluster1_L_1mm.nii --mni152reg --hemi lh --surf white --o lh.ROIA.mgh


Visualize surface:

/usr/local/freesurfer/subjects# freeview -f $FREESURFER_HOME/subjects/fsaverage/surf/lh.inflated:overlay='/usr/local/freesurfer/subjects/lh.ROIA.mgh'


Convert surface to annotation file:


/usr/local/freesurfer/subjects# mris_seg2annot --seg lh.ROIA.mgh --s fsaverage --h lh --ctab-auto --o lh.ROIA.annot

Project the atlas to the subject's brain:

/usr/local/freesurfer/subjects# mri_surf2surf --srcsubject fsaverage --trgsubject bert --hemi lh --sval-annot fsaverage/label/lh.ROIA.annot --tval bert/label/lh.bert.ROIA.annot

Calculate the atlas statistics:

/usr/local/freesurfer/subjects# mris_anatomical_stats -th3 -mgz -cortex $SUBJECTS_DIR/bert/label/lh.cortex.label -f $SUBJECTS_DIR/bert/stats/lh.ROIA.stats -b -a $SUBJECTS_DIR/bert/label/lh.bert.ROIA.annot bert lh white


Some questions:

The projection of the mask volume in the MNI152 space onto the fsaverage space is fully matched. Are there any crucial differences between these spaces?

How to get volume or surface file from annot file?

Best regards,

--
Beatriz Araújo Cavendish, MSc

PhD student | Psychologist

University of São Paulo

São Paulo/SP - Brazil