LAUSR

Clipping closure of large mucosal defects in the gastrointestinal tract can be difficult and time consuming, and sometimes requires many clips as the mucosa surrounding the defect stretches following endoscopic mucosal resection (EMR). Techniques utilizing the underwater method have been increasingly used in various endoscopic procedures [1–3]. Its application in clipping has been reported in large colonic and duodenal endoscopic submucosal dissection [4]. Here, we demonstrate the use of underwater clipping after EMR in the colon (▶Video 1). A 72-year-old man underwent a screening colonoscopy in which a 15-mm sessile elevated polyp (laterally spreading tumor, nongranular type) was discovered in the ascending colon (▶Fig. 1). Narrow-band imaging revealed adenoma with no invasive findings (▶Fig. 2). En bloc underwater EMR was performed using a bipolar snare (Dragonare; Zeon Medical Inc., Tokyo, Japan) (▶Fig. 3). After the defect had been examined, and confirmation had been obtained with carbon dioxide that there was no perforation, the lumen was filled with saline. The tension of themucosa around the defect decreased and the mucosa floated (▶Fig. 4). The defect size decreased, making it easier to catch the mucosa with the clips (SureClip; Micro-Tech, Nanjing, China). The defect was completely closed with four clips (▶Fig. 5). Underwater clipping was easier than the conventional under-gas method; it reduced both the procedure time and the number of clips.