Sa2045 MAGNETIC ANCHORING ASSISTED ENDOSCOPIC IRREVERSIBLE ELECTROPORATION FOR GASTRIC MUCOSAL ABLATION: A PRECLINICAL FEASIBILITY STUDY IN CANINE MODEL

Abstract

Irreversible electroporation (IRE) is an emerging non-thermal ablation technique which can achieve focal tissue ablation without thermal effects. Several preclinical studies have demonstrated the safety and efficacy of endoscopic IRE for common bile duct, gastrointestinal tract and peri-bronchial tissue ablation. The aim of this study was to evaluate the feasibility and safety of magnetic anchoring assisted endoscopic IRE for gastric mucosal ablation. The novel magnetic anchoring endoscopic ablation catheter and external magnetic anchoring device were developed with the support of numerical analysis and additive manufacturing. The catheter was 1800mm in length and 2.8mm in diameter. The tip of the catheter was round in shape with a couple of circle and donut electrode to form the bipolar electrode. A round magnet was fixed on the tip of catheter, so that the catheter can be controlled by the magnetic anchoring device. The endoscopic IRE for gastric mucosal ablation were performed by standard endoscopy in eight Beagle’s canines. Two to four lesions were performed in each animal. The experimental parameter of one set of IRE were 500V in voltage, 100μs in duration and 99 in pulse number. Magnetic anchoring time (MAT), total operation time (TOT) and other operation-related factors were evaluate for each ablation. Endoscopic examination were routine performed at 1 day, 3 days, 7 days, 14 days and 28 days post-IRE. Full-thickness gastric tissue were harvested by partial gastrectomy at 1 day and 7 days post-IRE for histopathological examination. H&E staining and TUNEL were performed to evaluate the efficacy of endoscopic IRE on gastric wall. Totally, 30 lesions were successfully performed by endoscopic IRE. Among them. 15 lesions were in anterior wall, 7 lesions were in posterior wall, 7 lesions were in greater curvature and 1 lesion was in lesser curvature. The median MAT was 300s (120-422.5s). The median TOT was 491.5s (358.3-632.5s). There was no difference in operation time between different parts of stomach. The catheter was fallen off in one case and minor displaced in six cases during IRE. No perforation or massive bleeding was observed during operation and follow-up days post IRE. Ulceration was observed starting from 3 days post-IRE. The injured mucosa was repaired within 14 to 28 days post-IRE. H&E staining showed inflammatory infiltration, edema and congestion in ablated mucosa. TUNEL showed diffuse positive cells in ablated mucosa, which indicating cell death. Magnetic anchoring assisted endoscopic IRE for gastric mucosal ablation is feasible and safe. It can be a potential therapeutic option for minimally invasive treatment of early gastric cancer or neoplasm.Operation time and histopathology examinationView Large Image Figure ViewerDownload Hi-res image Download (PPT)