Trigeminal nerve stimulation for epilepsy

Epilepsy in many patients remains poorly controlled despite the introduction of new antiepileptic drugs (AEDs).1 Neurostimulation, including vagus nerve stimulation (VNS), is a promising alternative to AEDs.2 The mechanism of VNS involves the locus ceruleus (LC) and nucleus solitarius (NTS).3,4⇓ As the LC and NTS project to the trigeminal nucleus, stimulation of the trigeminal nerve may also activate similar pathways to VNS.4-6⇓⇓ The trigeminal nerve, via cutaneous branches, offers a noninvasive method of neurostimulation. Recently, infraorbital trigeminal nerve stimulation (TNS) reduced pentylenetetrazol-induced seizures in rats.7 Given the potent antiepileptic effect in animals, we initiated a pilot study of infraorbital TNS for epilepsy. Research committee approval was obtained for a pilot study of TNS. Inclusion criteria were age of 18 to 65 years, four or more complex partial seizures (CPS) or secondarily generalized seizures per month, no significant cardiac or medical conditions, EEG demonstrating focal epileptic discharges, ability to maintain accurate seizure calendars, no trigeminal neuralgia, …