Efficacy of scissor-type knives for endoscopic mucosal dissection of superficial gastrointestinal neoplasms.

Endoscopic submucosal dissection (ESD) for superficial gastrointestinal neoplasms has become widespread. However, certain aspects of the procedure remain difficult to manage, such as intraoperative bleeding and perforation. There are two kinds of scissor-type knife: the Clutch Cutter (Fujifilm Co., Tokyo, Japan) and the SB knife (Sumitomo Bakelite Co., Tokyo, Japan). These knives have different features from other types of ESD knives and enable the performance of all ESD procedures, including mucosal incision, submucosal dissection, and hemostasis. The standard approach with scissor-type knives involves first grabbing the tissue and then incising or dissecting it. Theoretically, perforation as a result of unintentional movement should never happen with scissor-type knives compared to needle- or blade-type knives, which may induce perforation through unintentional movement. Moreover, the rates of severe bleeding and self-completion of ESD with scissor-type knives by non-experts were reported to be significantly better than for other knives. Thus, scissor-type knives can resolve these problems and help to further standardize ESD globally. In this review, we summarize reports on the efficacy of such scissor-type knives for ESD of gastrointestinal tumors. We also present the pocket-creation method and the application of traction devices, such as dental floss and S-O clips (Zeon Medical Co., Tokyo, Japan) for improving the performance of ESD with a Clutch Cutter.

Safety and Efficacy of a Same-Day Low-Volume 1 L PEG Bowel Preparation in Colonoscopy for the Elderly People and People with Renal Dysfunction.

INTRODUCTION: A same-day low-volume 1 L polyethylene glycol (PEG) for bowel preparation before colonoscopy was developed to improve patients' compliance. We aimed to evaluate the efficacy and safety of this regimen especially for the elderly and patients with renal dysfunction. METHODS: All consecutive patients who underwent colonoscopy in our center from November 2014 to September 2015 were included. Patients undertook a low-residue diet with 10 mL sodium picosulfate 1 day before colonoscopy. Subsequently, they had 1 L low-volume PEG (MoviPrep) and 0.5 L water 4 h before the examination. Clinical outcomes, including cleansing level using the Boston bowel preparation score (BBPS), in the elderly and special-elderly (65-79 and ≥80 years old) were analyzed and compared with the non-elderly (18-64 years old). Additionally, patients with renal dysfunction were analyzed with respect to both complications and changes in blood parameters. RESULTS: A total of 5427 patients (mean age: 64.5 ± 13.8) were analyzed. The rate of BBPS ≥ 6 in the elderly (2761 patients), special-elderly (565 patients), and non-elderly (2101 patients) was 94.1, 91.8, and 94.6 %, respectively. In the special-elderly, the rate of renal dysfunction was 14.8 %, and no severe complications were detected after colonoscopy. Additionally, there were no severe complications in 86 patients with renal dysfunction, though elevation of hematocrit was shown after intake of 1 L PEG (before, 36.7 ± 6.1 vs. after, 39.0 ± 5.7, P = 0.006). CONCLUSIONS: Our study shows the safety and efficacy of same-day low-volume 1 L PEG bowel preparation in colonoscopy for the elderly and patients with renal dysfunction.