Chemically assisted endoscopic mechanical submucosal dissection by using mesna

Background: A class of thiol compounds, mesna (sodium-2-mercaptoethanesulfonate), has been used to facilitate tissue dissection in surgical fields. Objectives: To evaluate the technical feasibility and efficacy of chemically assisted endoscopic mechanical submucosal dissection (CAEMSD) by using mesna. Design: An in vivo controlled blind trial by using porcine models. Settings: Nonsurvival study in an animal laboratory. Interventions: Six pigs were studied. Mucosal targets of about 2 cm (estimated) for treatment were created with a circle of cauterized spots along the greater curvature of the gastric body and the antrum. A mesna solution or the control hydroxypropyl methylcellulose solution was submucosally injected. The target mucosa was mechanically isolated with balloon dissection and removed by circumferential incision with a hook-knife inserted into the submucosal space. Necropsy and mucosal specimens from both groups were examined by histology. Results: En bloc resection of the target was achieved in all 8 attempts of the mesna group and in 7 of 8 attempts of the control group. Use of mesna significantly reduced tissue resistance to the initial balloon-catheter insertion into the submucosa and the technical difficulty of subsequent submucosal balloon dissection by using a subjective grading system (P < .05). There was no difference in histology between both groups. Conclusions: CAEMSD is a unique methodology to facilitate mucosal resection.