Neuromonitoring of the recurrent laryngeal nerve--a critical analysis of patients with postoperative nerve palsy

Abstract

The transligamental intraoperative neuromonitoring of the recurrent nerve is established in many surgical clinics as an useful and reliable technique. It is especially suitable to identify the recurrent nerve and to monitor its function during thyroid operation. We have analysed 14 early postoperative recurrent nerve palsies between June 1997 and December 2000 (1,23 % related to nerves at risk). As a result of complete follow up we found 4 permanent nerve palsies (0,35 % related to nerves at risk). In 11 out of 14 cases the neuromonitoring revealed a dysfunction of the recurrent nerve. The following long distance microsurgical preparation showed no interruption of the continuity of the nerve. Knowing the fact of unilateral negative monitoring signal we adapted our operative strategy. Therefore we did not observe bilateral nerve palsies. In 3 patients we found a positive nerve signal but nevertheless these patients showed postoperative unilateral recurrent palsies. The possible reasons are discussed. We are convinced that the neuromonitoring of the recurrent laryngeal nerve is an important progress in thyroid surgery.