A Novel Bipolar Polypectomy Snare Can Be an Alternative Choice for Endoscopic Resection

Objective: Endoscopic resection (ER) is more difficult and has a higher rate of complications, such as perforation and bleeding. The aim of this study was to evaluate the safety and feasibility of a bipolar polypectomy snare for ER.Methods: Initial ER procedures in live pigs were carried out. Then, a human feasibility study was performed in patients with colorectal polyps. Finally, the finite element method was used to evaluate the safety and effectiveness of the new bipolar snare.Results: In the live animal model, there were no significant differences in wound size and cutting time between monopolar and bipolar groups. The histological results (histological scores) of the two groups in porcine experiments were almost the same except that the incision flatness of bipolar group was better than that of the monopolar group. Incidence of bleeding and perforation was similar between the two groups in pigs' and patients' study. At last, the finite element model showed that the vertical thermal damage depth produced by bipolar snare system was approximately 71–76% of that produced by monopolar snare system at the same power.Conclusions: The novel bipolar snare is feasible in patients with colorectal polyps and can be an alternative choice for ERs.

Safety of Endoscopic Mucosal Resection Using a Bipolar Snare for Superficial Nonampullary Duodenal Epithelial Tumors and the Predictive Factors of Piecemeal Resection

<b><i>Introduction:</i></b> Endoscopic mucosal resection for small superficial nonampullary duodenal epithelial tumors is a noninvasive treatment; however, perforations can occur. Bipolar snares can reduce the risk of perforation due to small tissue damage. Currently, only few studies have reported endoscopic mucosal resection for small superficial nonampullary duodenal epithelial tumors using a bipolar snare and the effect of preoperative findings. <b><i>Objective:</i></b> To investigate (1) resectability and adverse events of endoscopic mucosal resection using a bipolar snare for small superficial nonampullary duodenal epithelial tumors and (2) the predictions of piecemeal resection. <b><i>Methods:</i></b> Between 2007 and 2017, 89 patients with 107 lesions underwent endoscopic mucosal resection using a bipolar snare. Among them, 88 lesions of 77 patients were evaluated. The primary outcome was the incidence of en bloc resection and R0 resection and adverse events. Risk factors associated with piecemeal resection, including preoperative lesion findings, were also examined. <b><i>Results:</i></b> The incidence rates of en bloc and R0 resections were 85.2 and 48.9%, respectively. Neither intraoperative or delayed perforations nor procedure-related mortality was noted. The nonlifting sign after submucosal injection was associated with an increase in piecemeal resection (odds ratio: 20.3, 95% confidence interval: 2.53–162; <i>p</i> = 0.005). <b><i>Conclusion:</i></b> Endoscopic resection for small superficial nonampullary duodenal epithelial tumors can cause perforation; however, endoscopic mucosal resection using a bipolar snare can be a safe treatment option as it does not cause perforations. The nonlifting sign after submucosal injection is a predictive factor for piecemeal resection.