J Endocr Surg.  2021 Dec;21(4):103-110. 10.16956/jes.2021.21.4.103.

The Use of Intermittent Intra-Operative Neural Monitoring in Reducing the Recurrent Laryngeal Nerve Palsy Rate in High-Risk Thyroidectomy

• Cheng KY
• Bryant Chan SY

• KMID: 2525965
• DOI: http://doi.org/10.16956/jes.2021.21.4.103

Abstract

Purpose
To determine if intra-operative neural monitoring (IONM) is effective in lowering the rate of recurrent laryngeal nerve (RLN) injury, when selectively applied in thyroidectomy for certain diagnoses which carry a higher risk of nerve injury.
Methods
A retrospective study of 175 patients (262 nerves at risk) undergoing ‘high-risk’ thyroidectomy, namely those for carcinoma, Graves’ disease, re-operations and retrosternal goitres, was performed using data extracted from the public hospitals electronic system. RLN palsy rates of those with IONM used or with visual identification of nerve alone (VA) were compared. RLN palsies were confirmed on flexible laryngoscopy.
Results
In the VA group, the rate of endoscopically confirmed temporary and permanent RLN palsy were 1.3% and 4.5%, respectively. There were no endoscopically confirmed RLN palsy in the IONM group. IONM use was associated with significantly less endoscopically confirmed RLN palsies (0 vs. 9, P=0.012). Permanent RLN palsies diagnosed either clinically and endoscopically were both significantly less in the IONM group (0 vs. 7, P=0.044). There was no significant reduction in the number of RLN palsy with the use of IONM in each highrisk subgroup.
Conclusion
In this study focusing on high-risk thyroidectomy, IONM has been shown to significantly reduce the permanent RLN palsy rate. The selective use of IONM presents a potential approach to demonstrate the beneficial effect of IONM in avoiding RLN injuries.

Keyword

Thyroidectomy; Thyroidectomy; Recurrent laryngeal nerve palsy; Recurrent laryngeal nerve palsy; Thyroid cancer; Thyroid cancer; Graves disease; Graves disease