ABSTRACT
BACKGROUND AND OBJECTIVES: ObjectivesZZRecurrent laryngeal nerve (RLN) injury is a potentially debilitating complication of thyroid surgery. In re-operative thyroid surgery, the risk of vocal fold paralysis increases significantly. This study evaluated the efficiency of intraoperative RLN monitoring using an electromyography (EMG) tube in an re-operative thyroid surgery and the prediction of postoperative neural function from the relationship between the intraoperative neuromonitoring response and postoperative vocal fold function. SUBJECTS AND METHOD: Sixty-nine patients undergoing reoperative thyroid surgery were divided into two groups: 37 patients underwent reoperative thyroid surgery with intraoperative neuromonitoring (EMG group) and 32 patients underwent reoperative thyroid surgery without intraoperative neuromonitoring (no EMG group). The prevalence of transient and permanent vocal fold paralysis was evaluated in each group. In addition, the sensitivity, specificity, and negative and positive predictive values of intraoperative neuromonitoring were evaluated. RESULTS: Transient and permanent vocal fold paralysis occurred in 8.1% (3/37) and 2.7% (1/37) of the EMG group and 12.5% (4/32) and 6.3% (2/32) of the no EMG group, respectively. The negative and positive predictive values of intraoperative neuromonitoring using an EMG tube in predicting postoperative vocal fold function were 100% and 57.1%, respectively. CONCLUSION: Although the differences were not significant, intraoperative neuromonitoring using the EMG tube resulted in shorter operating time, and less transient and permanent vocal fold paralysis during reoperative thyroid surgery. Intraoperative neuromonitoring using an EMG tube for reoperative thyroid surgery may be useful for preserving the postoperative vocal fold function.