Motor cortex stimulation for neuropathic facial pain.

Facial neuralgia is the last common pathway for a variety of pathological conditions with different etiology. Neuropathic facial pain is often refractory to routine medical or surgical treatments. We present here a long-term follow-up of two patients with unilateral facial neuropathic pain due to idiopathic trigeminal neuropathy or to surgical trauma to the glossopharyngeal nerve, respectively. These patients have been treated by other modalities for several years without obtaining satisfactory pain relief. Electrical stimulation of the motor cortex (MCS) with a quadripolar electrode contralateral to the painful area of the face was attempted in both cases for control of the facial pain, and resulted in immediate analgesia with more than 50% pain reduction. During a follow-up period of 72 months, a sufficient (> 50%) and stable analgesic effect of MCS was observed. These cases are discussed and the recent literature on MCS is reviewed in an attempt to identify indications for MCS as well as key structures in the brain for mediating the MCS effect.