Comparison of Robotic Versus Conventional Open Thyroidectomy for Recurrent Laryngeal Nerve Safety: A Systematic Review and Meta-Analysis.

This review aims to investigate the safety of recurrent laryngeal nerve (RLN) by comparing robotic thyroidectomy (RT) versus open thyroidectomy (OT) in Western and Asian populations. Two main outcomes of this review were (1) the safety of RLN comparing the robotic and OT assessing transient and permanent laryngeal nerve (PLN) palsy as a postoperative complication in each surgical procedure and (2) the safety of RLN comparing the robotic and OT assessing transient and permanent laryngeal nerve (PLN) palsy as a postoperative complication between studies conducted in USA/Europe and Asia. We searched relevant literature in electronic databases such as PubMed, MEDLINE, Cochrane CENTRAL, ScienceDirect, and Cumulative Index to Nursing & Allied Health (CINAHL) up to September 2022. Further research was performed during January 2024 in the Scopus database. Two primary outcomes were set: transient RLN palsy and permanent RLN palsy, comparing RT and OT. In this review, 18 non-randomized studies were included. A statistically significant difference between robotic and conventional OT was not observed either in transient RLN or in permanent RLN palsy. The odds ratio (OR) for the overall comparison of transient RLN palsy was 1.18, and the 95% confidence interval (95% CI) was 0.80-1.74. The subgroup analysis for transient RLN palsy between USA/Europe studies was OR 1.28, and the 95% CI was 0.64-2.58. The subgroup analysis for transient RLN palsy between Asian studies was OR 1.14, and the 95% CI was 0.72-1.82. The OR for the overall comparison of permanent RLN palsy was OR 0.90, and the 95% CI was 0.38-2.15. The subgroup analysis for permanent RLN palsy between USA/Europe studies was OR 0.45, and the 95% CI was 0.07-2.97. The subgroup analysis for permanent RLN palsy between Asian studies was OR 1.13, and the 95% CI was 0.42-3.05. Heterogeneity I2  was 0% in all outcomes. The Mantel-Haenszel method fixed effect was used. First, RT and open conventional thyroidectomy have comparable safety for RLN, although the analysis showed no statistically significant results. Second, no statistically significant results were found for RLN safety in either USA/Europe or Asian studies. Considering that there is not a statistically significant difference between the two approaches for RLN safety, and due to the limited number of studies from Western countries, the results should be considered with caution. Important factors such as the patient's body characteristics, the existing thyroid pathology, and the surgical approach should be kept in mind. More comparable studies are needed on the Western population.