Review
Copyright ©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Endosc. May 16, 2020; 12(5): 138-148
Published online May 16, 2020. doi: 10.4253/wjge.v12.i5.138
Optical imaging technology in colonoscopy: Is there a role for photometric stereo?
Benjamin M Shandro, Khemraj Emrith, Gregory Slabaugh, Andrew Poullis, Melvyn L Smith
Benjamin M Shandro, Andrew Poullis, Department of Gastroenterology, St George's University Hospitals NHS Foundation Trust, London SW17 0QT, United Kingdom
Khemraj Emrith, Melvyn L Smith, Centre for Machine Vision, University of the West of England, Bristol BS16 1QY, United Kingdom
Gregory Slabaugh, Department of Computer Science, City, University of London, London EC1V 0HB, United Kingdom
Author contributions: Shandro BM was involved in project administration and writing the original draft; Shandro BM, Emrith K, Slabaugh G, Poullis A and Smith ML were involved in conceptualization and editing; Poullis A and Smith ML were involved in supervision; all authors have read and approved the final manuscript.
Conflict-of-interest statement: The authors have nothing to disclose.
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: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Benjamin M Shandro, MBBS, MRCP, Research Fellow, Department of Gastroenterology, St George's University Hospitals NHS Foundation Trust, Blackshaw Road, Tooting, London SW17 0QT, United Kingdom. bshandro@nhs.net
Received: January 29, 2020
Peer-review started: January 29, 2020
First decision: April 12, 2020
Revised: May 8, 2020
Accepted: May 12, 2020
Article in press: May 12, 2020
Published online: May 16, 2020
Processing time: 107 Days and 15.4 Hours
Core Tip

Core tip: Dye-based chromoendoscopy has a stronger evidence base than existing virtual chromoendoscopy techniques for improving adenoma detection. However, it is inconvenient, and a novel approach is needed. Photometric stereo is a machine vision technique that captures surface normals. It has been applied successfully to colonic tissue and could be utilized in emerging computer-aided adenoma detection algorithms. However, the optimal method for processing specular reflections from colonic mucosa is unknown, and integration into commercial colonoscopy operating systems has not yet been attempted. Although photometric stereo could have a significant impact on colonoscopy in the future, that future remains distant.