Motor cortex stimulation: functional magnetic resonance imaging–localized treatment for three sources of intractable facial pain

Abstract

Neuropathic facial pain can be a debilitating condition characterized by stabbing, burning, dysesthetic sensation. With a large range of causes and types, including deafferentation, postherpetic, atypical, and idiopathic, both medicine and neurosurgery have struggled to find effective treatments that address this broad spectrum of facial pain. The authors report the use of motor cortex stimulation to alleviate 3 distinct conditions associated with intractable facial pain: trigeminal deafferentation pain following rhizotomy, deafferentation pain secondary to meningioma, and postherpetic neuralgia. Functional MR imaging was used to localize facial areas on the precentral gyrus prior to surgery. All 3 patients experienced long-lasting complete or near-complete resolution of pain following electrode implantation. Efficacy in pain reduction was achieved through variation of stimulation settings over the course of treatment, and it was assessed using the visual analog scale and narrative report. Surgical complications included moderate postsurgical incisional pain, transient cerebral edema, and intraoperative seizure. The authors' results affirm the efficacy and broaden the application of motor cortex stimulation to several forms of intractable facial pain.