Once SAMSEG has finished segmenting T2 lesions, other than trying different --threshold flags, any way to manually modify them?

Can --eTIV be added to SAMSEG?

In Samseg, can brainstem be segmented into parts, such as medulla, pons, mid brain like through recon all? 

Can corpus callosum be segmented separately in Samseg?

Sorry for all the questions.

Many thanks.