Clinical and Translational Research
Copyright ©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Jul 14, 2020; 26(26): 3767-3779
Published online Jul 14, 2020. doi: 10.3748/wjg.v26.i26.3767
SpyGlass application for duodenoscope working channel inspection: Impact on the microbiological surveillance
Tao-Chieh Liu, Chen-Ling Peng, Hsiu-Po Wang, Hsin-Hung Huang, Wei-Kuo Chang
Tao-Chieh Liu, Wei-Kuo Chang, Division of Gastroenterology, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei 114, Taiwan
Chen-Ling Peng, Department of Integrated Diagnostics & Therapeutics, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei 10002, Taiwan
Hsiu-Po Wang, Division of Gastroenterology and Hepatology, Department of Internal Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei 114, Taiwan
Hsin-Hung Huang, Division of Gastroenterology, Cheng Hsin General Hospital, National Defense Medical Center, Taipei 114, Taiwan
Author contributions: Liu TC, Peng CL and Chang WK contributed to design of the study, making critical revisions related to important intellectual content of the manuscript, and final approval of the version of the article to be published; Wang HP and Huang HH contributed to analysis and interpretation of data.
Supported by the Ministry of Defense-Medical Affairs Bureau, Tri-Service General Hospital, No. TSGH-D-109182.
Institutional review board statement: This study was reviewed and approved by the Ethics Committee of the Tri-Service General Hospital, National Defense Medical Center, Taiwan.
Informed consent statement: Patients were not required to give informed consent to the study because the analysis used anonymous clinical data that were obtained after each patient agreed to treatment by written consent.
Conflict-of-interest statement: All authors declare that they have no conflicts of interest.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (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:
Corresponding author: Wei-Kuo Chang, MD, PhD, Associate Professor, Division of Gastroenterology, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, No. 325, Chengong Road, Sec.2, Neihu, Taipei 114, Taiwan.
Received: February 16, 2020
Peer-review started: February 16, 2020
First decision: May 1, 2020
Revised: May 28, 2020
Accepted: June 23, 2020
Article in press: June 23, 2020
Published online: July 14, 2020
Processing time: 147 Days and 5.2 Hours
Research background

The working channels of endoscopes are subjected to wear and tear. Damaged channels allow bacteria to adhere and hide, and the biofilms that form are subsequently difficult to remove. Visual channel inspection has been proposed as a quality control measure for endoscope reprocessing.

Research motivation

Endoscopes with damaged working channels have been considered as sources of microbiological contamination. The FDA recommended returning duodenoscopes to the manufacturer for inspection, servicing, and maintenance at least once a year. Visual inspection may identify certain abnormalities and improve endoscopic quality and care of duodenoscope reprocessing. However, many questions have been raised regarding the visual inspection findings on working channels in real-world situations. Studies related to such situations are too limited to provide sufficient information.

Research objectives

We aimed to investigate the type, severity, location, and clinical significance of visual inspections inside patient-ready duodenoscopes.

Research methods

Visual inspection of channels was performed in 19 duodenoscopes. Inspections were recorded and reviewed to evaluate for channel damage (scratches, buckling, and stains), debris (dark-colored debris, light-colored debris, and other debris), and fluids (clear fluid and opaque fluid). Visual inspection findings were used to analyze the relevance of microbiological surveillance.

Research results

We found 72 abnormal visual inspection findings in the 19 duodenoscopes viewed in our study, including scratches (n = 10, 52.6%), buckling (n = 15, 78.9%), stains (n = 14, 73.7%), debris (n = 14, 73.7%), and fluids (n = 6, 31.6%). Duodenoscopes > 12 mo old had a significantly higher number of abnormal visual inspection findings than those ≤ 12 mo old (46 findings vs 26 findings, P < 0.001). Multivariable regression analyses demonstrated that the bending section had a significantly higher risk of being scratched, buckled, and stained, and accumulating debris than the insertion tube. Debris and fluids showed a significant positive correlation with microbiological contamination (P < 0.05).

Research conclusions

In patient-ready duodenoscopes, scratches, buckling, stains, debris, and fluids inside the working channel are common. Presence of debris and fluids increases the susceptibility to microbiological contamination. The presence of fluids was found to be an independent factor for bacterial culture positivity. Visual channel inspection using the SpyGlass visualization system may be added to the existing visual inspection recommendations to identify suboptimal reprocessing or endoscopes requiring repair or replacement.

Research perspectives

Endoscopists should routinely or intermittently visualize the working channel during working hours. Early detection of these abnormal visual inspection findings may allow timely reporting to the manufacturers and promote prompt performance of quality assurance interventions before the channel lumen becomes comprised, which could impair manual cleaning.