A novel method of endoscopic submucosal dissection with blunt abrasion by submucosal injection of sodium carboxymethylcellulose: an animal preliminary study

BACKGROUND: Endoscopic submucosal dissection (ESD), particularly the process of submucosal incision with a knife, is technically difficult and carries a high risk of perforation. Submucosal injection of a viscous substance, eg, jelly, obviates the need of submucosal incision with a knife. Sodium carboxymethylcellulose (SCMC), known as cellulose gum, is highly viscous when dissolved in water. OBJECTIVE: To evaluate the efficacy and the safety of ESD by submucosal injection of SCMC solution in a porcine stomach. DESIGN AND SETTING: A prospective, single-center study. INTERVENTIONS: The viscosity of various concentrations (0.5%-3.5%) of SCMC was measured by a viscometry. First, we injected 10 mL of various concentrations of SCMC solution into the submucosal layer of resected porcine stomachs in vitro and examined whether the submucosal injection dissected the mucosal layer from the muscular layer by EUS. Second, we performed ESD by injecting, with an 18-gauge needle, the SCMC solution into the submucosal layer of the stomach in white domestic pigs in vivo to evaluate the efficacy and the safety of SCMC for ESD. MAIN OUTCOME MEASUREMENTS AND RESULTS: Submucosal injection of the SCMC solution dissected most of the mucosal layer from the muscular layer at the concentration above 2.0%. We, therefore, decided to use 2.5% SCMC for ESD with a 18-gauge needle to ensure dissection. Submucosal injection of 2.5% SCMC dissected the mucosal layer from the muscular layer without complications, such as massive bleeding or perforation, in white domestic pigs. Histologically, injection of 2.5% SCMC revealed no damage to the muscular layer and surrounding tissue. LIMITATIONS: Our novel injection technique was evaluated in an animal model with a normal stomach; it was relatively easy to approach the target mucosa. CONCLUSIONS: ESD by submucosal injection of viscous SCMC solution appeared to be an easy, safe, and technically efficient method for dissection of gastric lesions.