Large colorectal mucosal defect closure post-endoscopic submucosal dissection using the reopenable clip over line method and modified locking-clip technique

Mucosal defects during extensive colorectal endoscopic submucosal dissection (ESD) cause post-ESD bleeding [1], and a method to close these defects has not yet been established. In recent years, the usefulness of a method for closing mucosal defects after colorectal ESD using a line and clips has been reported [2]. Therefore, we invented a new clip-line closure method called the "reopenable clip over line method" (ROLM), which uses a line (0.23-mm nylon line) and reopenable clips (SureClip; 8 or 16 mm; MC Medical, Tokyo, Japan) to close large colorectal mucosal defects. We also proposed a method of fixing the line to the first and second clips after the mucosal defect had been closed with thread-assisted mucosal defect closure using the locking-clip technique (LCT) [3]. However, LCT is difficult technically because it requires fixation by threading a line through the gap between the teeth at the base of the clip (EZ clip, HX-610-90S; Olympus) in the intestinal tract [4]. Therefore, we proposed a modified LCT (M-LCT) that involves performing the LCT by inserting the line through the gap between the teeth at the base of the clip before it is passed through the accessory channel of the endoscope.