title: Clinical Significance of Invasive Motor Cortex Stimulation for Trigeminal Facial Neuropathic Pain Syndromes.
abstract: BACKGROUND
  Invasive neuromodulation of the cortical surface for various chronic pain syndromes has been performed for >20 years. The significance of motor cortex stimulation (MCS) in chronic trigeminal neuropathic pain (TNP) syndromes remains unclear. Different techniques are performed worldwide in regard to operative procedure, stimulation parameters, test trials, and implanted materials.
  
  
  OBJECTIVE
  To present the clinical experiences of a single center with MCS, surgical approach, complications, and follow-up as a prospective, noncontrolled clinical trial.
  
  
  METHODS
  The implantation of epidural leads over the motor cortex was performed via a burr hole technique with neuronavigation and intraoperative neurostimulation. Special focus was placed on a standardized test trial with an external stimulation device and the implementation of a double-blinded or placebo test phase to identify false-positive responders.
  
  
  RESULTS
  A total of 36 patients with TNP were operated on, and MCS was performed. In 26 of the 36 patients (72%), a significant pain reduction from a mean of 8.11 to 4.58 (on the visual analog scale) during the test trial was achieved (P < .05). Six patients were identified as false-positive responders (17%). At the last available follow-up of 26 patients (mean, 5.6 years), active MCS led to a significant pain reduction compared with the preoperative pain ratings (mean visual analog scale score, 5.01; P < .05).
  
  
  CONCLUSIONS
  MCS is an additional therapeutic option for patients with refractory chronic TNP, and significant long-term pain suppression can be achieved. Placebo or double-blinded testing is mandatory.
  
  
  BACKGROUND
  MCS, motor cortex stimulationNRS, numeric pain rating scaleTNP, trigeminal neuropathic or deafferentation painVAS, visual analog scale.
authors.affiliation: Department of Neurosurgery, University Hospital of Schleswig-Holstein, University of Lübeck, Lübeck, Germany.
authors.forename: Dirk
authors.initials: D
authors.lastname: Rasche
authors.forename: Volker M
authors.initials: VM
authors.lastname: Tronnier
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004599:Electric Stimulation Therapy / Q000379:methods*; D004824:Epidural Space / Q000601:surgery; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009044:Motor Cortex; D038361:Neuronavigation; D019635:Neurosurgical Procedures; D010147:Pain Measurement; D011446:Prospective Studies; D019919:Prosthesis Implantation; D013577:Syndrome; D016896:Treatment Outcome; D014277:Trigeminal Neuralgia / Q000628:therapy*