Intraoperative Neuromonitoring in Thyroid Surgery: A Systematic Review

Area of Science:

• Otolaryngology
• Surgical Neurology
• Endocrinology

Background:

• Recurrent laryngeal nerve palsy (RLNP) is a risk in thyroid surgery.
• Intraoperative neurophysiologic monitoring (IONM) is used to detect nerve function during surgery.
• Factors contributing to false positives in IONM require evaluation.

Purpose of the Study:

• To assess the efficacy of IONM in preventing RLNP during thyroidectomy.
• To evaluate the predictive power of IONM for recurrent laryngeal nerve (RLN) function.
• To identify factors contributing to false-positive IONM results.

Main Methods:

• Systematic review of MEDLINE, EMBASE, and PubMed databases.
• Inclusion of 17 studies comparing thyroid surgery with and without IONM (30,926 patients).
• Pooled analysis of data to determine specificity and positive predictive power (PPP) of IONM.

Main Results:

• Mean specificity of IONM was 90.24% for identifying functional nerves.
• Mean positive predictive power (PPP) was low, with substantial variation.
• No statistically significant difference in RLNP rates between IONM and control groups (3.18% vs 3.83%).

Conclusions:

• IONM is not recommended as the standard of care for thyroidectomies.
• Low PPP and potential complications may stem from lack of standardized negative-signal cutoff or intubation injury.
• Further research needed to refine IONM protocols and interpret signals.