Hi Snoopy,
This is something that was offered to me but scared me to death. Its done by a pain doc , usually in his/her office and basically they burn the nerve and reset it. Not specifically for dystonia like deep brain stimulation is. There are many injections that are done to the neck to help relieve pain but often for dystonic patients botox is used, in large amounts. There is also in person support groups , that are helpful to connect with others finding good docs, the key is to have a movement neurologist if you think its dystonia.