Society: ASGE

Background: Endoscopic defect closure have been applied to reduce the adverse events rate after colorectal endoscopic submucosa dissection (ESD). As for the suturing device, the closure has usually been performed using through-the-scope clips (TTSC). However, suturing of large defects is challenging because clips are usually small and insufficient for closing mucosal defects. In addition, closure of a large wound by simple clipping usually results in suturing only the mucosal layer, which could be unreliable. Suturing all layers of the colorectal wall, like surgical suturing, is important for achieving robust closure. Although closure with over-the-scope clips or over-the-scope sutures allows robust closure, even for large defects, these methods require expensive dedicated devices. In addition, delivery to the proximal colon is sometimes difficult and time-consuming. Therefore, a suturing method using only TTSC, which can perform robust closure even for large mucosal defects, is necessary. Endoscopic double-layered suturing was reported to be a method that involves suturing not only the mucosal layer, but also the submucosal layer. In this method, TTSCs are applied on the submucosal layer at the center of the ulcer to shrink the defect and suture the mucosa and submucosa together. We noticed that introducing reopenable clips enabled us to gently fold muscle layers as well as the submucosal layer. Making a few folded muscle layers allowed complete closure of even extremely large defects. This modified double layered suturing is like folding origami which is the Japanese traditional art of folding paper. We speculated that this method, origami method (OGM), achieved reliable closure of even large defects, like surgical suturing. This study aimed to evaluate the feasibility of OGM for colorectal post-ESD defects. Methods: This retrospective observational study was conducted at a tertiary care hospital. We reviewed the cases of OGM attempted after colorectal ESD at our institute between October 2021 and October 2022, and measured the clinical characteristics and outcomes of enrolled cases. Results: The OGM was attempted in 47 cases after colorectal ESD. Thirty-one cases (66%) were in the proximal colon; five (11%) in the distal colon; six (13%) in the upper rectum; and five (10%) in the lower rectum. The median resected specimen size was 38 mm, the largest being 85 mm. Complete closure was achieved in 44 cases (94%), including the largest case and all lower rectum cases. There were no perforations caused by clips during closure, and delayed perforation and bleeding were not observed. Conclusions: This new suturing method, like surgical all layer suturing, is feasible and recommended. The OGM could achieve reliable closure of large defects in any location, including the proximal colon and thick-walled lower rectum, using only TTSC.

<b>Modified double layered suturing, origami method (OGM)</b>

Modified double layered suturing, origami method (OGM)

Noriko Matsuura

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