Int J Thyroidol.  2018 Nov;11(2):109-116. 10.11106/ijt.2018.11.2.109.

Development of the Novel Intraoperative Neuromonitoring for Thyroid Surgery

  • 1Department of Otolaryngology-Head and Neck Surgery, Pusan National University Yangsan Hospital, Pusan National University School of Medicine, Yangsan, Korea.
  • 2Department of Otolaryngology-Head and Neck Surgery, Pusan National University Hospital, Pusan National University School of Medicine, Busan, Korea.


It is very important to identify recurrent laryngeal nerve (RLN) and prevent RLN injury during thyroid surgery. The intraoperative neuromonitoring (IONM) for the prevention of RLN injury is a useful method because it can identify the location and status of RLN and predict postoperative vocal cord function easily. The IONM consists of a stimulating side that applies electrical stimulation to the nerve and a recording side that measures the surface electromyography (EMG) of the vocal cord muscle through electrode endotracheal tube. The nerve stimulator and surgical dissector are separate instruments. So, during IONM for the prevention of the RLN injury in conventional, endoscopic, or robotic thyroid surgery, repeated exchanging between surgical instruments and the nerve stimulator is inconvenient and time consuming. On the recording side, the accuracy of the electrode endotracheal tube which measures the EMG of the vocalis muscle can be affected by contact with between electrode and vocal fold and position change of patient. We would like to introduce recent several researches to overcome the current limitations of IONM.


Thyroid surgery; Intraoperative neuromonitoring; Recurrent laryngeal nerve; Attachable nerve stimulator; Surface bio-pressure sensor

MeSH Terms

Electric Stimulation
Laryngeal Muscles
Recurrent Laryngeal Nerve
Surgical Instruments
Thyroid Gland*
Vocal Cords


  • Fig. 1 This is a photograph that automatic periodic stimulation (APS) wraps the left vagus nerve. It can periodically stimulate the vagus nerve to check the laryngeal nerve status in real-time.

  • Fig. 2 A nerve probe composed of magnets. The developed nerve probe (below), which is a magnetically deformed conventional nerve probe (top), can be easily attached to and detached from a metallic surgical instrument.

  • Fig. 3 Endoscopic or robotic nerve probe. A conventional nerve probe was deformed (A) and connected to an endoscopic or robotic surgical instrument (B) to the site where the electrocautery was connected.

  • Fig. 4 A nerve probe attached to an energy based devices. Authors attached a nerve probe to the inactive blade of the harmonic focus (A) and the lower blade of the LigaSure (B).

  • Fig. 5 A laryngeal electromyography electrodes. (A) Medtronic electrode endotracheal tube. (B) Inomed laryngeal adhesive electrode.

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Clin Exp Otorhinolaryngol. 2019;12(4):420-426.    doi: 10.21053/ceo.2019.00423.

Intraoperative Neuromonitoring System Using Needle and Skin Electrode during Thyroid Surgery
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Int J Thyroidol. 2022;15(1):17-22.    doi: 10.11106/ijt.2022.15.1.17.


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