INTRAOPERATIVE MONITORING OF THE VAGUS NERVE DURING INTRACRANIAL GLOSSOPHARYNGEAL AND UPPER VAGAL RHIZOTOMY - TECHNICAL NOTE

INTRACRANIAL SECTION OF the glossopharyngeal and upper vagal rootlets for the treatment of vagoglossopharyngeal neuralgia may cause dysphagi a or vocal cord paralysis from injury to the motor vagal rootlets in 1 0% to 20% of cases. To minimize this complication, we recently applied a technique of intraoperative monitoring of the vagus nerve (previous ly described by Lipton and McCaffery to monitor the recurrent laryngea l nerve during thyroid surgery) in a patient undergoing intracranial r hizotomy for vagoglossopharyngeal neuralgia. By inserting an electrode in the ipsilateral false vocal cord and stimulating the rostral vagal rootlets intraoperatively under general anesthesia, we could differen tiate the rostral vagal motor rootlets from the sensory rootlets. In t his patient, the technique allowed us to preserve a rostral vagal root let, which if sectioned, could have caused dysphagia or vocal cord par alysis. We conclude that intraoperative monitoring of the rostral vaga l rootlets is an important technique to minimize complications of uppe r vagal rhizotomy.