Related Experiment Video
Updated: May 28, 2025
Intra-Operative Neural Monitoring of Thyroid Surgery in a Porcine Model
Published on: February 11, 2019
Feasibility of Cricothyroid Muscle Needle Electrode for Monitored Thyroidectomy
Wen Liang Joel Lau1, Che-Wei Wu2, Man Hon Tang3
1Department of Head and Neck Surgery, Division of Surgery and Surgical Oncology, Singapore General Hospital, National Cancer Centre Singapore, Singapore, Singapore.
Objectives:
Preservation of the recurrent laryngeal nerve (RLN) and external branch of the superior laryngeal nerve (EBSLN) is essential to maintain voice function after thyroidectomy. Intraoperative neuromonitoring (IONM) assists in nerve preservation. This study compares three IONM modalities, endotracheal surface electrode (ETSE), thyroid cartilage needle electrodes (TCNE), and cricothyroid muscle needle electrode (CTNE), in their monitoring of laryngeal muscle electromyographic (EMG) amplitude.
Methods:
An observational prospective cohort study included 29 patients (21F:8M) undergoing thyroidectomy for Bethesda III-VI nodules or benign nodules >4 cm. EMG amplitudes were recorded via ETSE, TCNE, and CTNE following stimulation of the EBSLN, RLN, and vagus nerve (VN).
Results:
A total of 105 nerves at risk were assessed, including 35 EBSLNs, 35 VNs, and 35 RLNs. The recorded amplitudes at S1 for the ETSE, TCNE, and CTNE were 45.6 ± 60.7 μV, 403.7 ± 865.4 μV, and 3049.4 ± 2749.8 μV. The CTNE demonstrate significantly higher S1 amplitudes and positive signal rates compared with both the TCNE and ETSE (p < 0.001). For V1, the recorded amplitudes for the ETSE, TCNE, and CTNE were 453.7 ± 406.7 μV, 1363.9 ± 1063.6 μV, and 700 ± 375.1 μV. For R1, the recorded amplitudes for the ETSE, TCNE, and CTNE were 567.1 ± 556 μV, 1544.6 ± 1269.6 μV, and 720.4 ± 363.1 μV. With a threshold of 100 μV to determine positive signal, CTNE detected all EBSLN, VN, and RLN signals, whereas TC missed 13 cases (37.1%) of EBSLN.
Conclusion:
The CTNE showed a higher positive signal rate than ETSE and TCNE in detection of EBSLN, whereas it showed similar performance with TCNE in detection of VN and RLN. CTNE is a viable option for IONM during thyroidectomy.
Level Of Evidence:
2 Laryngoscope, 135:1843-1849, 2025.
