Intraoperative neuromonitoring of the recurrent laryngeal nerve during thyroid and parathyroid surgery

Czech version

Authors: Jan Mejzlík ^1,2; Michal Homoláč ^1,2; L. Školoudík ^1,2; P. Kordač ¹; Z. Dufek ¹; K. Néma ^1,2; E. Tusay ¹; V. Chrobok ^1,2
Authors‘ workplace: Klinika otorinolaryngologie a chirurgie hlavy a krku, FN Hradec Králové ¹; Lékařská fakulta v Hradci Králové, UK, Praha ²
Published in: Otorinolaryngol Foniatr, 75, 2026, No. 3, pp. 231-237.
Category: Original Article
doi: https://doi.org/10.48095/ccorl2026231

Overview

Introduction: Recurrent laryngeal nerve (RLN) injury is among the most serious complications of thyroid and parathyroid surgery. It may result in dysphonia, dysphagia, and, in bilateral cases, respiratory insufficiency. Intraoperative neuromonitoring (IONM) enables functional assessment of the RLN during surgery and serves as an important adjunct to visual nerve identification. Cohort: The retrospective study included 544 patients (431 women, 79.2%; 113 men, 20.8%) who underwent surgery at the Department of Otorhinolaryngology and Head and Neck Surgery, University Hospital Hradec Králové, between 2022 and 2025 using IONM. Benign thyroid disorders accounted for 61.4% of cases, thyrotoxicosis for 14.2%, parathyroid diseases for 7.5%, and malignant tumours for 10.7%. Methods: IONM was performed using the NIM Vital system with an endotracheal tube equipped with integrated surface electrodes and intermittent RLN stimulation at 1 mA. Electromyographic responses and signal latencies were evaluated at initial nerve identification and after completion of dissection. Results were analysed according to diagnosis and compared with a historical control cohort comprising 2,965 thyroid procedures performed between 2010 and 2025. Results: In the control cohort, implementation of systematic IONM was associated with a reduction in the overall incidence of RLN paresis from 5.22 to 3.72% (P = 0.0423). The incidence of permanent paresis decreased from 2.08 to 0.91% (P = 0.0113). These findings are consistent with published data and suggest a beneficial effect of IONM on functional outcomes in high-risk procedures. Conclusion: Intraoperative neuromonitoring represents an important tool for improving the safety of thyroid and parathyroid surgery. The results of our cohort are consistent with international experience and suggest that systematic use of IONM may contribute to reducing the incidence of recurrent laryngeal nerve injury, particularly in high-risk surgical procedures.

Keywords:

thyroid gland – Electromyography – thyroidectomy – nerve injury – parathyroidectomy – parathyroid glands – recurrent laryngeal nerve – intraoperative neuromonitoring

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