INTRAOPERATIVE NEUROMONITORING DOES NOT DECREASE THE RISK OF VOCAL CORD PALSY ASSOCIATED WITH THYROID CANCER SURGERIES, BUT CUMULATIVE EXPERIENCE OVER TIME MAY

AUTHORS:
M.Y. Oh (Seoul, Korea, Republic of) , H.L. Bae (Seoul, Korea, Republic of) , M. Han (Seoul, Korea, Republic of) , C. Wu (Kaohsiung, Taiwan) , Y.J. Chai (Seoul, Korea, Republic of)
Background:
This study aimed to evaluate the influence of intraoperative neuromonitoring (IONM) on vocal cord palsy (VCP) rates, identify risk factors, and assess the trend of VCP rates over time.
Methods:
Consecutive patients who underwent thyroidectomy for thyroid cancer between March 2014 and June 2022 were retrospectively reviewed. VCP rates were compared between non-IONM and IONM groups stratified by the date of surgery. Univariate and multivariate analyses were conducted to identify risk factors of VCP, and prevalence of VCP was observed over time.
Results:
A total of 712 patients (485 females and 227 males) were included in the analysis. The rates of transient and permanent VCP did not significantly differ between non-IONM and IONM groups. Transient VCP occurred in 4.6% patients and 4.3% patients in the non-IONM and IONM groups, respectively (p = 0.878). Permanent VCP occurred in 0.7% and 0.4% patients in the non-IONM and IONM groups, respectively (p = 0.607). Among the nerves at risk in the non-IONM and IONM groups respectively, transient damage occurred in 2.8% and 3.0% cases (p = 0.901), and permanent damage occurred in 0.4% and 0.3% cases (p = 0.688). Multivariate analysis revealed no significant risk factors for VCP. There was a statistically significant decreasing trend in VCP rates over time as the cumulative number of cases increased (p = 0.017).
Conclusions:
IONM did not significantly reduce the risk of VCP. However, the surgeon's experience may have a role in reducing risk, as evidenced by the decreasing trend of VCP rates over time.