Introduction: Recurrent laryngeal nerve (RLN) identification is the gold standard in thyroidectomy. However, due to the anatomical variation of the RLN, it can be difficult to be identified especially by the less experienced surgeon. Meta-analysis showed that IONM did not significantly reduce the number of permanent RLN injuries but may be helpful in difficult or more complicated cases. Most of the studies were performed at the established centre with experienced surgeons. This study aims to find out whether the IONM will be helpful to junior, less experienced surgeons.
Objective: This study aimed to demonstrate that the IONM system does help a junior surgeon in identifying RLN compared to visualization alone (VA).
Methodology: A total of 40 nerve-at-risks from 25 patients who underwent thyroidectomies were randomized into IONM and VA group. Intraoperatively, the IONM system was set according to the guideline set by International Neural Monitoring Study Group, and standard thyroidectomy was performed. After medial rotation, the junior surgeon will start searching for the RLN with IONM or VA according to patient's group within 8 minutes. If the nerve was not found, a senior surgeon will proceed accordingly.
Results: There was no difference in the demographic data (age, gender, ethnicity, and thyroid pathology) within both groups. The junior surgeon was able to find 90% of RLN using IONM compared to 60% by VA (p = 0.028). There was no RLN injury
Conclusion: Intraoperative nerve monitoring does help junior surgeons to identify RLN compared to VA within the test duration. This can be used as a teaching tool without compromising the safety of the patient.
Clinical significance: Intraoperative nerve monitoring is a useful tool not only to identify the RLN, hence reducing injury to it but also helps junior surgeons practicing to identify the nerve. It is more important when dealing with an anatomical variation of the nerve.
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