D 201 12704

Of the 395 lesions removed by colorectal ESD performed between April 2018 and March 2022, 6 lesions with insufficient description of data on preoperative and/or pathological tumor diameter and 12 lesions with incomplete resection were excluded. Finally, we collected 377 lesions in this study (Figure 1).
ESD indication criteria were based on the Japanese Colorectal ESD/EMR guidelines[4 (link)]. We mainly used the PCF-290ZI endoscope (Olympus Co., Ltd., Tokyo, Japan) with a transparent straight hood (D-201-12704; Olympus) under carbon dioxide insufflation. A 0.4% sodium hyaluronate solution (Ksmart; Olympus) diluted five times with normal saline, which included a small amount of indigo carmine, was used for submucosal injection. A mucosal incision was made around the tumor, and submucosal dissection for en bloc removal was performed using the DualKnife (KD-655Q; Olympus). A high-frequency generator (VIO 3; Erbe Elektromedizin GmbH, Tübingen, Germany) was used during ESD. ST-hood (DH-29CR; Fujifilm Co., Ltd., Tokyo, Japan), hemostatic forceps (FD-411QR; Olympus), or other endoscopic devices were used according to the situation. The transanally retrieved specimen was promptly spread, pinned on a sponge board, and immersed into 10% neutral buffered formalin for fixation for histological evaluation by pathologists.

Colon pretreatment was performed using 0.15-L magnesium citrate on the night before the ESD and using 1.2 to 2-L low-volume polyethylene glycol solution (Moviprep, EA Pharma Co. Tokyo, Japan) on the day of ESD. When the stool became clear, colon preparation was considered complete. If the stools were not clear after taking 2 L of low-volume polyethylene glycol solution, 120-mL glycerine enema or isotonic magnesium citrate solution was used.
ESD was performed using a colonoscope with a waterjet instrument (PCF-H290, CF-HQ290 or PCF-H290T; Olympus, Tokyo, Japan) and an attachment (D-201-12704; Olympus) fitted to the tip. Incision and dissection were performed with a FlushKnife BTS (DK2620 J -B15S-; Fujifilm) or a DualKnifeJ (KD-655Q; Olympus, Tokyo, Japan). Precut-coagulation of vessel or hemostasis was performed with Coagrasper (FD-411QR; Olympus, Tokyo, Japan). In addition, hyaluronic acid (MucoUp; Boston scientific Tokyo, Japan) with a small volume of epinephrine and indigo carmine was injected.
High-frequency power supply (VIO300D; Erbe, Tübingen, Germany) was used. The endocut I mode (effect 3, duration 2, interval 2) was used for mucosal incision and submucosal dissection. The forced coagulation mode 45 W (effect 2) was used for submucosal dissection, and the soft coagulation mode 80 W (effect 5) was used for precut-coagulation and hemostatic treatment.

Considering the general condition of the patients, the operators decided to perform bowel preparation using either polyethylene glycol or an enema, and in some cases, no specific bowel preparation was performed. In most cases colonoscopy was performed using a PCF-Q260JI or PCF-H290I scope (Olympus Medical Systems, Tokyo, Japan). Other scopes (CF-Q260AI, PCF-H290Z, PCF-H290TI, or PCF-PQ260L, Olympus Medical Systems; EC-590MP, FUJIFILM, Saitama, Japan) were also used for colonoscopy. The scope was used with a soft cap (D201-10704, D201-11804, D201-12704, or D201-13404; Olympus Medical Systems) and water jet device in all colonoscopies. Endoscopic treatment for CDB with SRH was performed at the discretion of the individual operators. Clipping was predominantly conducted using hemoclips (HX-610-135S or HX-610-135, Olympus Medical Systems; ROCC-D-26-195-C, Micro-Tech, Nanjing, China). These hemoclips were used for the so-called direct method (Fig. 2d), where they were placed on the vessel as close to the bleeding as possible (23 (link)). In contrast, indirect clipping was performed in the Zipper fashion when either the source of the bleeding could not be confirmed due to massive bleeding or it was difficult to insert the clip into the diverticulum (23 (link)).

All patients with ALGIB, except those with renal dysfunction or contrast medium allergy, underwent contrast-enhanced computed tomography (CT). For the remaining patients, the decision to perform plain CT was left to the physicians' discretion.
Colonoscopy was performed with a water-jet scope (PCF- Q260AZI, PCF-Q260JI, PCF-H290I, or GIF-Q260J; Olympus Medical Systems, Tokyo, Japan) with a soft hood (D201-12704; Olympus Medical Systems) attached after bowel preparation using polyethylene glycol, unless the patient was hemodynamically unstable. Colonoscopy was performed by expert or nonexpert endoscopists under supervision. Expert endoscopists were defined as institutional teaching staff of St. Luke's International Hospital who were also board-certified members of the Japanese Society of Gastroenterology and had performed more than 5,000 routine colonoscopies. Nonexpert endoscopists were not board-certified but had performed more than 500 routine colonoscopies before performing endoscopic hemostasis. The most frequently performed initial therapy for CDB was EC with Hemoclips (HX-600-090 L, HX-600-135, HX-610-090 L, or HX-610-135; Olympus Optical, Tokyo, Japan) from January 2008 to May 2009, and EBL with a band ligator device (MD-48710 EVL Device or MD-48912B EBL Device; Sumitomo Bakelite, Tokyo, Japan) from June 2009 to December 2019.