Irreversible electroporation of the bile duct in swine: A pilot study.

Abstract

541 Background: Irreversible electroporation (IRE) is a relatively new ablative method. However, the application of IRE ablation has not been attempted for the treatment of biliary disease. Minimally invasive approach using endoscopic retrograde cholangio-pancreatography (ERCP) can be a novel therapeutic modality for IRE ablation. In this study, we investigated the feasibility and effect of endoscopic IRE for biliary tract in animal model. Methods: A new catheter electrode was developed for endoscopic IRE ablation of biliary tract. The electrode for IRE ablation has two band-shaped electrodes on catheter tip. We performed ERCP and endoscopic IRE ablations on normal common bile duct in 6 Yorkshire pigs. Experimental parameters of IRE were 500V/cm, 1000V/cm and 2000V/cm (under 50 pulses, 100 µs length). Animals were sacrificed after 24 hours and ablated bile duct were collected. H & E stain, immunohistochemistry and western blot were performed. Results: Well-demarcated focal color changes were observed on the mucosa of the common bile duct under all experimental parameters. After IRE ablation, bile duct epithelium was disappeared around ablated area and it showed fibrotic change in H&E stain. Depth of change after IRE was different between each experimental parameters. Apoptotic change of bile duct was localized around mucosa in 500V. Diffuse transmural fibrosis of bile duct was shown after IRE ablation with 2000V. TUNEL immunohistochemistry showed the cell death of bile duct mucosa and submucosa along the electrode. Within 24 hours, no complication was observed in pigs after endoscopic IRE ablation. Conclusions: Endoscopic IRE ablation using ERCP was successfully performed on common bile duct by using catheter-shaped electrode. It can be a potential therapeutic option as minimally invasive ablation for treatment of biliary tumors.