World Journal of Surgery

, Volume 42, Issue 1, pp 137–142 | Cite as

Development of a Novel Detachable Magnetic Nerve Stimulator for Intraoperative Neuromonitoring

  • Eui-Suk Sung
  • Jin-Choon Lee
  • Sung-Chan Shin
  • Sung-Won Choi
  • Da-Woon Jung
  • Byung-Joo LeeEmail author
Original Scientific Report



Recurrent laryngeal nerve (RLN) palsy is a serious complication of thyroid surgery. During intraoperative neuromonitoring (IONM) of the RLN in thyroid surgery, repeated shifting between surgical instruments and the nerve stimulator is cumbersome and time-consuming. Therefore, we developed a simple detachable magnetic nerve stimulator that may be connected to all metallic surgical instruments. This study aimed to investigate the feasibility and efficacy of this detachable magnetic nerve stimulator for IONM in a porcine model and humans.


Eight RLNs in four pigs and thirteen in nine patients that underwent thyroidectomy were examined. We developed a detachable nerve stimulator that combined surgical instruments with the nerve-stimulating probe. We evaluated the electromyography (EMG) amplitudes of the RLNs in pigs and patients using conventional nerve probes and surgical instruments with the novel detachable magnetic nerve stimulator attached.


The EMG amplitudes of the eight RLNs in pigs and thirteen in patients were analyzed. The detachable magnetic nerve stimulator was feasible and safe. There was no significant difference in the EMG amplitude between instruments (P = 0.423 in animals, P = 0.446 in humans).


The application of stimulating dissection using a detachable magnetic nerve stimulator during thyroidectomy with IONM is simple, convenient, and effective. It provides surgeons with real-time feedback of the EMG response during intermittent IONM. We propose that this novel device could be an essential guide for most surgeons, especially for less experienced head and neck surgeons.



The authors appreciate Prof. Jung- Hoon Ro at the Biomedical Engineering Department at Pusan National University Hospital for his help in developing the instrument.

Compliance with ethical standards

Conflict of interest

The authors have no conflicts of interest or financial ties to disclose.


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Copyright information

© Société Internationale de Chirurgie 2017

Authors and Affiliations

  • Eui-Suk Sung
    • 1
  • Jin-Choon Lee
    • 1
  • Sung-Chan Shin
    • 2
  • Sung-Won Choi
    • 2
  • Da-Woon Jung
    • 2
  • Byung-Joo Lee
    • 2
    Email author
  1. 1.Department of Otolaryngology - Head and Neck Surgery and Research Institute for Convergence of Biomedical Science and Technology, College of MedicinePusan National UniversityYangsanKorea
  2. 2.Department of Otolaryngology - Head and Neck Surgery, College of Medicine and Medical Research InstitutePusan National UniversityBusanKorea

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