Observational Study
Copyright ©The Author(s) 2017. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Mar 7, 2017; 23(9): 1657-1665
Published online Mar 7, 2017. doi: 10.3748/wjg.v23.i9.1657
Usefulness of a novel slim type FlushKnife-BT over conventional FlushKnife-BT in esophageal endoscopic submucosal dissection
Yoshiko Ohara, Takashi Toyonaga, Namiko Hoshi, Shinwa Tanaka, Shinichi Baba, Hiroshi Takihara, Fumiaki Kawara, Tsukasa Ishida, Yoshinori Morita, Eiji Umegaki, Takeshi Azuma
Yoshiko Ohara, Namiko Hoshi, Tsukasa Ishida, Yoshinori Morita, Eiji Umegaki, Takeshi Azuma, Division of Gastroenterology, Department of Internal Medicine, Graduate School of Medicine, Kobe University, Kobe 650-0017, Japan
Takashi Toyonaga, Shinwa Tanaka, Fumiaki Kawara, Department of Endoscopy, Kobe University Hospital, Kobe 650-0017, Japan
Shinichi Baba, Hiroshi Takihara, Department of Endoscopy, Kishiwada Tokushukai Hospital, Kishiwada 596-0042, Japan
Author contributions: Ohara Y, Toyonaga T and Hoshi N contributed mainly to this work; Tanaka S, Baba S, Takihara H, Kawara F and Ishida T participated in the analysis, and interpretation of the data; Morita Y, Umegaki E and Azuma T supervised the report.
Institutional review board statement: The study was reviewed and approved by the Ethics Committees of Kobe University Hospital No. 160051 and Kishiwada Tokushukai Hospital No. 28-10.
Informed consent statement: All study participants provided informed written consent prior to study enrollment.
Conflict-of-interest statement: Dr. Toyonaga invented FlushKnife-BT and FlushKnife-BTS in conjunction with Fujifilm and receives royalties from their sales.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Takashi Toyonaga, MD, PhD, Department of Endoscopy, Kobe University Hospital, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan. toyonaga@med.kobe-u.ac.jp
Telephone: +81-78-3825774 Fax: +81-78-3826309
Received: October 25, 2016
Peer-review started: October 26, 2016
First decision: December 1, 2016
Revised: December 28, 2016
Accepted: January 11, 2017
Article in press: January 11, 2017
Published online: March 7, 2017
Abstract
AIM

To investigated the usefulness of a novel slim type ball-tipped FlushKnife (FlushKnife-BTS) over ball-tipped FlushKnife (FlushKnife-BT) in functional experiments and clinical practice.

METHODS

In order to evaluate the functionality of FlushKnife-BTS, water aspiration speed, resistance to knife insertion through the scope, and waterjet flushing speed were compared between FlushKnife-BTS and BT. In clinical practice, esophageal endoscopic submucosal dissection (ESD) performed using FlushKnife-BTS or BT by an experienced endoscopist between October 2015 and January 2016 were retrospectively reviewed. The treatment speed and frequency of removing and reinserting the knife to aspirate fluid and air during ESD sessions were analyzed.

RESULTS

Functional experiments revealed that water aspiration speed by the endoscope equipped with a 2.8-mm working channel with FlushKnife-BTS was 7.7-fold faster than that with conventional FlushKnife-BT. Resistance to knife insertion inside the scope with a 2.8-mm working channel was reduced by 40% with FlushKnife-BTS. The waterjet flushing speed was faster with the use of FlushKnife-BT. In clinical practice, a comparison of 6 and 7 ESD using FlushKnife-BT and BTS, respectively, revealed that the median treatment speed was 25.5 mm2/min (range 19.6-30.3) in the BT group and 44.2 mm2/min (range 15.5-55.4) in the BTS group (P = 0.0633). However, the median treatment speed was significantly faster with FlushKnife-BTS when the resection size was larger than 1000 m2 (n = 4, median 24.2 mm2/min, range 19.6-27.7 vs n = 4, median 47.4 mm2/min, range 44.2-55.4, P = 0.0209). The frequency of knife replacement was less in the BTS group (median 1.76 times in one hour, range 0-5.45) than in the BT group (7.02 times in one hour, range 4.23-15) (P = 0.0065).

CONCLUSION

Our results indicate that FlushKnife-BTS enhances the performance of ESD, particularly for large lesions, by improving air and fluid aspiration and knife insertion during ESD and reducing the frequency of knife removal and reinsertion.

Keywords: Endoscopic submucosal dissection, Novel slim type ball-tipped FlushKnife, Ball-tipped FlushKnife, Resistance to knife insertion, Water aspiration speed

Core tip: Devices utilized in endoscopic submucosal dissection (ESD) play an important role in facilitating the safe and effective procedure. A novel slim type ball-tipped FlushKnife (FlushKnife-BTS) has been developed to enhance the performance of aspiration and insertion of the knife through the scope. We herein investigated the usefulness of FlushKnife-BTS over FlushKnife-BT in functional experiments and clinical practice. FlushKnife-BTS showed a faster water aspiration speed, reduced resistance to knife insertion, a faster treatment speed when the resection size was large, and low frequency of knife replacement. Our results indicate that FlushKnife-BTS supports the efficient performance of ESD, particularly for large lesions.