Emerging Technique: Stag Beetle Knife for Zenker's Diverticulum - A Meta-Analysis of Safety and Efficacy

Abstract

Background and aim: The SB Knife, a unique scissor-shaped device with rotating insulated monopolar blades, is increasingly employed in the endoscopic management of ZD, and this systematic review and meta-analysis aims to evaluate its overall safety, efficacy, and feasibility. Methods A thorough search of electronic databases and conference abstracts was conducted until November 2023. Meta-analysis utilized the random-effects model, with I2% assessing heterogeneity. Subgroup analysis was based on sample size, employing SMD and a 95% confidence interval (CI) for continuous variables. Key outcomes included clinical success, recurrence rate, adverse events, and improvement in dysphagia score. Results Incorporating eight studies with 299 patients (60.5% males), mean age 72.75 ± 2.86 years, and ZD size 2.66 ± 0.52 cm, procedures lasted 23.06 ± 10.00 minutes. Clinical success was achieved in 86% (95% CI: [81–90; I2 0%]) after 10.98 sessions and 22.74% required multiple (up to 4) sessions. The recurrence rate was 15% [11–20; I2 0%]. Intraprocedural complications occurred in 9% [5–13; I2 = 29%], primarily minor bleeding (9.6%), micro-perforation (2%), odynophagia (1.3%), and fever (1.05%). Late-onset bleeding occurred in 3.2% after 1 week. Adverse events were conservatively managed, and subgroup analysis by sample size indicated a significant difference in mean sessions (p = 0.02). Dysphagia score improvement was SMD (95% CI) 1.59 [2.27–0.91; I2 97%], p < 0.01, with a mean 22.23 ± 11.47 months follow-up. Conclusion The meta-analysis confirms SB knife's success in ZD, displaying excellent safety and dysphagia improvement; however, further research is needed to define optimal patient cohorts and compare them with other management techniques.