Underwater and traction-assisted endoscopic submucosal dissection in the gastric fundus using a multibending endoscope

The gastric fundus is the most challenging site for endoscopic submucosal dissection (ESD) because accessing the fundus with the tip of the endoscope is difficult. Furthermore, the wall of the fundus is thin and the knife-edge is pointed towards the muscle layer. A combination of the previously reported effective methods, namely, a multibending endoscope [1], multiloop traction [2], and underwater technique [3] may offer safe treatment in the fundus. Herein, we report a successful ESD performed by a trainee using these three methods. A 58-year-old woman presented with a 10-mm type 0-IIa gastric adenocarcinoma (fundic gland type) in the gastric fundus (▶Fig. 1). ESD was performed using a multibending endoscope (GIF-2TQ260M; Olympus, Tokyo, Japan) and a DualKnife J (KD-655L; Olympus, Tokyo, Japan) by an endoscopist who was inexperienced in fundal surgery, under the supervision of an experienced surgeon (▶Video 1). Although a conventional endoscope cannot reach the fundus, this area can be easily accessed with a multibending endoscope, so enabling an easy peripheral incision. Dissection of the submucosa was complicated because the stomach was tense with air and the knife-edge was facing the muscle layer. Once the stomach had been sufficiently degassed, the knife-edge was nearly parallel to the muscle layer; however, the resulting field of view for the procedure was unsatisfactory. Therefore, underwater ESD was performed, which enables safe dissection in the nondilated stomach, with the knife nearly parallel to the muscle layer, but with a good field of view (▶Fig. 2). Furthermore, the respiratory movement was suppressed using this method. After the flap had been created, a multiloop traction device (Boston Scientific, Marlborough, Massachusetts, USA) was attached, and traction was applied in the E-Videos