Dear FS experts,
I am trying to extract values for cortical thickness, surface area and volumes, from different functional ROIs. These cortical ROIs have been defined using SPM tools, and are in .nii format. My scans have been processed using FS v5.3.
Although the conversion seems to go well, the “end product” does not really look good, some of the extracted ROI for some subjects are empty. Does anyone have a clue of why?
Here is what I have done:
1) transform .nii file to .mgz file
$FREESURFER_HOME/bin/mri_convert $MASKS_DIR/ROI.nii $MASKS_DIR/L_ROI.mgz $FREESURFER_HOME/bin/mri_convert $MASKS_DIR/ROI.nii $MASKS_DIR/R_ROI.mgz
2) to make sure our masks from SPM will match fsaverage templates, I did
tkmedit -f $MASKS_DIR/avg152T1.mgz -overlay $MASKS_DIR/L_ROI.mgz -fthresh 0.5 tkmedit -f $MASKS_DIR/avg152T1.mgz -overlay $MASKS_DIR/R_ROI.mgz -fthresh 0.5
It was fine.
3) I created a .dat file containing the registration matrix from avg152T1 onto fsaverage
cd $SUBJECTS_DIR/fsaverage/surf spmregister --s fsaverage --mov $MASKS_DIR/avg152T1.nii --reg $REG_DIR/avg152T1_to_fsaverage.dat
4) Visualisation of the registration
tkregister2 --mov $MASKS_DIR/avg152T1.nii --targ $SUBJECTS_DIR/fsaverage/mri/brainmask.mgz --reg $REG_DIR/avg152T1_to_fsaverage.dat --surf orig
The registration was bad, so… I manually relocate the TAL template onto the fsaverage template and saved a new avg152T1_to_fsaverage.dat file called avg152T1_to_fsaverage_edited.dat. This file is used for the next steps.
5) Visualisation of the registration of our mask onto fsaverage T1
cd $SUBJECTS_DIR/fsaverage/surf tkmedit fsaverage T1.mgz \ -overlay $MASKS_DIR/L_ROI.mgz \ -overlay-reg $REG_DIR/avg152T1_to_fsaverage_edited.dat \ -fthresh 0.5 \ -surface lh.white -aux-surface rh.white
tkmedit fsaverage T1.mgz \ -overlay $MASKS_DIR/R_ROI.mgz \ -overlay-reg $REG_DIR/avg152T1_to_fsaverage_edited.dat \ -fthresh 0.5 \ -surface lh.white -aux-surface rh.white
Up to this sep, everything looks good.
6) Transformation of the ROI mask to surface and thickness
mri_vol2surf --src $MASKS_DIR/L_ROI.mgz --reg $REG_DIR/avg152T1_to_fsaverage_edited.dat --hemi lh --o $MASKS_DIR/L_ROI.mgh mri_vol2surf --src $MASKS_DIR/R_ROI.mgz --reg $REG_DIR/avg152T1_to_fsaverage_edited.dat --hemi rh --o $MASKS_DIR/R_ROI.mgh
mri_cor2label --i $MASKS_DIR/L_ROI.mgh --surf fsaverage lh --id 1 --l $MASKS_DIR/L_ROI.label mri_cor2label --i $MASKS_DIR/R_ROI.mgh --surf fsaverage rh --id 1 --l $MASKS_DIR/R_ROI.label
7) Extraction of the ROI surface and thickness for analyses
mris_anatomical_stats -l $MASKS_DIR/L_ROI.label -f $OUT_DIR/results_L_ROI_SubjID SubjID lh mris_anatomical_stats -l $MASKS_DIR/R_ROI.label -f $OUT_DIR/results_R_ROI_SubjID SubjID rh
Thanks to anyone who will be able to help me with that!
Yann