Nerve Stimulation or Gamma Knife (radiation)

I've been searching for relief since 2004. Doctors previously have treated me for migraine or trigeminal autonomic cephalalgia (TAC) (I've tried numerous abortive and preventive meds - but I am still in pain). However a new neurologist described at least part of my problem as atypical facial pain or a facial neuralgia - and that the problem is with my trigeminal nerve.

Is facial pain considered a headache? - Guess its not a migraine.

The doc is thinking that an implanted nerve stimulation device or a gamma knife procedure (highly focused radiation on part of the nerve) may help me. Anyone else have any experience with either of these procedures?

Thanks in advance for any replies.