Utility of intraoperative nerve monitoring in thyroid surgery: 20-year experience with 1418 cases

The efficacy of intraoperative nerve monitoring is controversial in the literature. This study of a single surgeon's experience seeks to determine if the use of intraoperative nerve monitoring influences recurrent laryngeal nerve injury during thyroid surgery.

Six hundred fifty-seven patients with normal pre-operative vocal fold function underwent thyroid surgery without the use of intraoperative nerve monitoring from September 1997 to January 2007, while 761 patients underwent thyroid surgery from February 2007 to February 2016 with routine use of nerve monitoring. Patients were followed for a minimum of 6 months after surgery, and postoperative nerve function was determined by fiberoptic laryngoscopy. A Fisher test was used to determine if nerve injury was statistically different between both groups.

In patients operated on without nerve monitoring, 21 patients were found to have postoperative vocal fold paralysis with nine regaining functioning. In patients operated on with nerve monitoring, 27 were found to have vocal fold dysfunction with 17 regaining function. Fisher test analysis, both with and without patients regaining function, showed no difference in nerve injury between groups (p > 0.05, p > 0.05).

Intraoperative monitoring during thyroidectomy may not prevent injury to the recurrent laryngeal nerve.