Tu1541 The Usefulness of a Newly Developed It Knife for Rectal Endoscopic Submucosal Dissection in an Established Experimental Simulation Model

Abstract

Figure 1. Survival Curves of all 283 Patients who Underwent Colorectal ESD Tu1541 The Usefulness of a Newly Developed It Knife for Rectal Endoscopic Submucosal Dissection in an Established Experimental Simulation Model Yunho Jung*, IL-Kwun Chung, Young Sin Cho, Tae Hoon Lee, Sang-Heum Park, Sun-Joo Kim Gastroenterology, Soon Chun Hyang Cheonan Hospital, Cheonan, Republic of Korea Background/Aims: Colorectal endoscopic submucosal dissection (ESD) is still challenging because it has some dsadvantages such as technical difficulty, a long procedure time and higher complication rate such as bleeding (about 10%) and perforation (4w10%). The newly developed IT knife (IT-knife nano, Olympus Optical Co., Tokyo, Japan) was designed for colorectal ESD. It has a smaller insulation tip and small disk blade perpendicular to the main blade for improving the movability in small lumen and safety with reducing burning effect on muscle layer. The aim of this study was to evaluate the efficacy of newly developed IT knife for the rectal ESD in comparison with conventional ESD. Methods: This study was designed as a prospective, controlled, and ex-vivo study. A total of 40 standardized artificial lesions measuring 3 x 3 cm was created approximately 10 cm from anal verge in fresh ex vivo porcine colorectal specimens using the EASIE-R simulator platform (Endosim LLC, Berlin, MA). An experienced endoscopist completed each 20 cases of ESD with conventional ESD knifes such as dual and hook knife (Conventional knife group) and 20 cases with newly developed IT knife (New knife group). Independent observer recorded circumferential resection time, submucosal dissection time, total procedure time, injection amount, En bloc and perforation rate. Results: The mean size of resected specimen was 4.1 0.6 cm (Long axis) x 3.7 0.4 cm (Short axis). The mean submucosal dissection time (6.4 2.9 vs 10.5 3.8 minutes; PZ0.01) and total procedure time (13.2 4.5 vs 18.0 6.2 minutes; PZ0.008) were significantly shorter in the new knife group in comparison with the conventional knife group. The mean injection frequency of new knife group was significantly smaller than conventional knife group (2.1 0.3 vs 2.6 0.6, PZ0.006). There was only one perforation (1/20) in conventional knife group. The en bloc rate was 95% (19/20) in both groups. Conclusion: Newly developed IT knife seems to be safe and reduce the time for rectal ESD in ex-vivo setting. Further animal or clinical trial needed for proving the new knife’s clinical benefit. Results of conventional knife group and new knife group AB578 GASTROINTEST Conventional Knife group (20) INAL ENDOSCOPY Vo New knife group (20) lume 79, No. 5 P value Circumferential cutting (minutes) 3.9 1.5 3.4 1.4 0.275 Submucosal dissection (minutes) 10.5 3.8 6.4 2.9 0.001 Total procedure time (minutes) 18.0 6.2 13.2 4.5 0.008 Injection amount (cc) 27.3 11.1 24.8 7.9 0.416 Injection frequency 2.6 0.6 2.1 0.3 0.006 S : 2014 Conventional Knife group (20) New knife