afni.nimh.nih.gov

I'm not completely clear as to what you are trying to do. It may be useful to provide some example commands you have tried. To display an ROI in suma, you have some choices.

1. Map the ROI volume to the surface with 3dVol2surf.
2. Make a surface for the ROI volumes with IsoSurface
3. Show the ROI as a volume with "suma -vol myrois.nii"