Comparative Validation of Polyp Detection Methods in Video Colonoscopy: Results from the MICCAI 2015 Endoscopic Vision Challenge

Colonoscopy is the gold standard for colon cancer screening though still some polyps are missed, thus preventing early disease detection and treatment. Several computational systems have been proposed to assist polyp detection during colonoscopy but so far without consistent evaluation. The lack of publicly available annotated databases has made it difficult to compare methods and to assess if they achieve performance levels acceptable for clinical use. The Automatic Polyp Detection subchallenge, conducted as part of the Endoscopic Vision Challenge (http://endovis.grand-challenge.org) at the international conference on Medical Image Computing and Computer Assisted Intervention (MICCAI) in 2015, was an effort to address this need. In this paper, we report the results of this comparative evaluation of polyp detection methods, as well as describe additional experiments to further explore differences between methods. We define performance metrics and provide evaluation databases that allow comparison of multiple methodologies. Results show that convolutional neural networks (CNNs) are the state of the art. Nevertheless it is also demonstrated that combining different methodologies can lead to an improved overall performance

Biopsy Sampling in Upper Gastrointestinal Endoscopy : A Survey from 10 Tertiary Referral Centres across Europe

Funding Information: A. Link reports grants from European Commission “Eu-ropäischer Fond für regionale Entwicklung” (EFRE), outside the submitted work. In Lithuania the work was partly supported by Lithuanian Research Council Grant no APP-2/2016. In Latvia, the methodological support was made available from the project lzp-2018/1-0135. This work was also supported by the NIHR Oxford Biomedical Research Centre (The views expressed are those of the authors and not necessarily those of the NIHR or the Department of Health and Social Care). In Barcelona, we thank the CERCA Programme/Generalitat de Catalunya for the support. Publisher Copyright: © 2020 The Author(s) Published by S. Karger AG, Basel.Background: Guidelines give robust recommendations on which biopsies should be taken when there is endoscopic suggestion of gastric inflammation. Adherence to these guidelines often seems arbitrary. This study aimed to give an overview on current practice in tertiary referral centres across Europe. Methods: Data were collected at 10 tertiary referral centres. Demographic data, the indication for each procedure, endoscopic findings, and the number and sampling site of biopsies were recorded. Findings were compared between centres, and factors influencing the decision to take biopsies were explored. Results: Biopsies were taken in 56.6% of 9,425 procedures, with significant variation between centres (p < 0.001). Gastric biopsies were taken in 43.8% of all procedures. Sampling location varied with the procedure indication (p < 0.001) without consistent pattern across the centres. Fewer biopsies were taken in centres which routinely applied the updated Sydney classification for gastritis assessment (46.0%), compared to centres where this was done only upon request (75.3%, p < 0.001). This was the same for centres stratifying patients according to the OLGA system (51.8 vs. 73.0%, p < 0.001). More biopsies were taken in centres following the MAPS guidelines on stomach surveillance (68.1 vs. 37.1%, p < 0.001). Biopsy sampling was more likely in younger patients in 8 centres (p < 0.05), but this was not true for the whole cohort (p = 0.537). The percentage of procedures with biopsies correlated directly with additional costs charged in case of biopsies (r = 0.709, p = 0.022). Conclusion: Adherence to guideline recommendations for biopsy sampling at gastroscopy was inconsistent across the participating centres. Our data suggest that centre-specific policies are applied instead.publishersversionPeer reviewe

Indications of endoscopic ultrasonography-guided fine needle aspiration (EUS FNA) in subepithelial tumors

s), nous aborderons ici uniquement ces tumeurs

Endoscopic ultrasound-guided celiac plexus neurolysis using a reverse phase polymer

AIM: To assess the feasibility of endoscopic ultrasound (EUS)-guided celiac plexus neurolysis (CPN) using a poloxamer.METHODS: in this prospective evaluation, six Yorkshire pigs underwent EUS-guided CPN. Three received an injection of 10 mL of 0.25% Lidocaine plus methylene blue (group 1) and three received an injection of 10 mL of 0.25% Lidocaine plus blue colored poloxamer (PS137-25) (group 2). Necropsy was performed immediately after the animals were sacrificed. the abdominal and pelvic cavities were examined for the presence of methylene blue and the blue colored poloxamer.RESULTS: EUS-guided CPN was successfully performed in all 6 pigs without immediate complication. Methylene blue was identified throughout the peritoneal and retroperitoneal cavity in group 1. the blue colored poloxamer was found in the retroperitoneal cavity immediately adjacent to the aorta, in the exact location of the celiac plexus in group 2.CONCLUSION: EUS-guided CPN using a reverse phase polymer in a non-survival porcine model was technically feasible. the presence of a poloxamer gel at the site of the celiac plexus at necropsy indicates a precise delivery of the neurolytic agent. (C) 2010 Baishideng. All rights reserved.Generalitat de Catalunya (AGAUR)Brigham & Womens Hosp, Div Gastroenterol, Boston, MA 02115 USAUniversidade Federal de São Paulo, BR-04023062 São Paulo, BrazilHosp Clin Barcelona, Dept Gastroenterol, Endoscopy Unit, E-08036 Barcelona, SpainUniversidade Federal de São Paulo, BR-04023062 São Paulo, BrazilGeneralitat de Catalunya (AGAUR): BE-100022Web of Scienc