Laryngeal Motor Evoked-potentials as a Biomarker of Vagus Nerve Stimulation in Epileptic Patients

The goal of this study is to record and characterize larynx evoked motor potentials induced by vagus nerve stimulation. This study will include 10 adult patients implanted with a Vagus nerve stimulator, followed at the Center for Refractory Epilepsy at Cliniques St Luc. The inclusion criteria are: (1) patient aged between 18 and 65 years ; (2) cervical VNS device (Cyberonics, Houston, TX, USA) implanted for at least 6 months, (3) normal electrode impedance of the electrode. Exclusion criteria are (1) presence of a concomitant laryngeal pathology or recurrent laryngeal nerve damage, independent from VNS ; (2) important VNS side effects reported by the patient, such as severe dyspnea (grade III-IV) or severe pain in the neck/ear region.