[Freesurfer] combining a stroke lesion label with aseg.presurf.mgz

Hello FreeSurfer expert,

I have a binarized stroke masks of 200 stroke patients that were hand traced. Since, we have a lot of patients, it will take a lot of time to edit the aseg.presurf.mgz. The stroke masks were drawn in the native space and I want to bring them into the freesurfer space, and combine with the aseg.presurf.mgz/stamp it onto the aseg.presurf.mgz and then run recon-all -autorecon2-noaseg -autorecon3.

I have done the first part: 1) mri_convert -rl /subject/mri/brainmask.mgz -rt nearest stroke.nii stroke.mgz (use freeview to check the accuracy)

I want to combine the stroke.mgz with the aseg.presurf.mgz in order to create a new ROI. what command should I use to accomplish this? Thanks

Best,

Paul