Kd 655l

Full-thickness resection was performed by employing a standard single-channel endoscope (GIT-H290, Olympus). A transparent cap (D-201-11304; Olympus) was attached to the front of the endoscope. An IT knife (KD-611 L; Olympus, Tokyo, Japan) and a Dual Knife (KD-655 L; Olympus) were used for incision and dissection. A clip (ROCC-D-26-195, Microtech Nanjing, China) and a snare (Snare Master; Olympus; Japan) were used to assist in the traction of lesions. A high frequency generator (ICC-200, ERBE, Erbe Elektromedizin GmbH, Tübingen, Germany) and hot biopsy forceps (FD-410LR, Olympus) were used to achieve intraoperative haemostasis. Other equipment consisted of injection needles (NM-4L-1, Olympus), endoloops (LeCampTM, Changzhou, China), and carbon dioxide insufflation (Olympus).

ER was defined as endoscopic mucosal resection with a cap-fitted panendoscope (EMRC) and ESD. The decision to resect with ESD or EMRC depended on the size of the lesion, and the final decision was made by the endoscopist.
The video processor unit EVIS LUCERA SPECTRUM, EVIS LUCERA ELITE, or EVIS X1 (Olympus Corporation, Tokyo, Japan) and a single-channel upper gastrointestinal endoscope (GIF-Q260J, GIF-H290T; Olympus Co.) were used.
For ESD, hyaluronic acid (MucoUP; Boston Scientific, Tokyo, Japan or Ksmart; Olympus Co.) was used for submucosal injection. A DualKnife (KD-655Q or KD-655L, Olympus Co.), IT-nano knife (KD-612L, Olympus Co.), and Splash M-knife (Pentax Medical, Japan) were used for submucosal dissection.
For EMRC, snare (SD-221L-25, Olympus Co) was used for resection.

A Tibet miniature pig (16–22 kg) was provided by Dongguan Songshanhu Experimental Animal Technology Co., Ltd., China. All the experimental procedures in this study were approved by the guidelines of the Animal Ethics Committee for Yin She Guangzhou Medical Technology Co., Ltd., China. The pig was treated following the Laboratory Animal Care and Use Guidelines strictly. The pig was only allowed to drink water at 2 d before experiment. The pig was anesthetized by xylazine hydrochloride and propofol, endotracheal intubation was performed with continuous oxygen intake of 2 L/min. An endoscope was entered into the pig's stomach for observation. Subsequently, 3.0 mL of GGH-E or NS-E was injected into submucosa with an endoscopic needle (NET2422-C4, Endo-Flex, Germany) at front wall or back wall of the gastric antrum. Thereafter, shape change of submucosal cushion was observed by the endoscope at 0, 10 and 30 min after endoscopic injection, and the obtained images were recorded and analyzed. On the other hand, 5.0 mL of NS-E, GGH or GGH-E was injected into submucosa and then mucosa was resected by an electrosurgical knife (KD-655L, Olympus, Japan). The obtained images were recorded to observe the hemostatic effect.