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Misawa, Masashi

https://orcid.org/0000-0002-8520-2036

Mayo Clinic

SHOWA Medical University Northern Yokohama Hospital

Citations 6

Environmental impact of computer-aided diagnosis in colonoscopy: a carbon footprint assessment of a prospective study cohort
Olabintan, Olaolu , Halvorsen, Natalie , Baddeley, Robin , Kudo, Shin-ei, Barua, Ishita , Misawa, Masashi , Hunt, Claire , Nilsen, Jens Aksel , Frigstad, Svein Oskar , Rastogi, Amit, Holme, Øyvind , Gulati, Shraddha , Hassan, Cesare , Hayee, Bu , Mori, Yuichi , Kudo, Shin-ei, Mori, Kensaku , Hunt, Claire, East, James E. , Hassan, Cesare , Kalager, Mette , Løberg, Magnus , Haji, Amyn , Bretthauer, Michael , Mori, Yuichi

Endoscopy | October 7, 2025 | Volume: 58 | Issue: 03 | Pages: 303-309

10.1055/a-2717-8365 Get It

Abstract The environmental impact of computer-aided diagnosis (CADx) in colonoscopy is unknown. The potential to reduce greenhouse gas emissions by limiting unnecessary polypectomies may be offset by emissions associated with CADx devices. We quantified and compared the carbon footprint of colonoscopy with and without CADx. Life-cycle carbon emissions associated with endoscopic snares, polyp traps, histopathology, and CADx devices were estimated using life-cycle assessment software. The effect of CADx was estimated by the carbon dioxide equivalent (CO2e) emissions related to outcomes from a prospective cohort of patients who underwent colonoscopy with optical diagnosis under a leave-in-situ strategy (i.e. rectosigmoid polyps ≤5 mm predicted as non-neoplastic were not removed) with and without CADx assistance. We analyzed 1134 individuals (median age 67 years, 59% male) with 1716 colorectal polyps. Colonoscopy with CADx reduced the number of snares and polyp traps from 567 to 543 (difference: 24) and histopathology submissions from 1343 to 1278 (difference: 65). However, the total carbon footprint increased from 832 kg CO2e (95%CI 815 to 847) without CADx to 946 kg CO2e (95%CI 927 to 965) with CADx, corresponding to an absolute increase of 114 kg CO2e (95%CI 80 to 150) or 0.10 kg CO2e per colonoscopy. Using CADx under a leave-in-situ strategy increased the environmental burden of colonoscopy.
Computer‐aided detection for esophageal achalasia (with video)
Shiwaku, Hironari , Misawa, Masashi , Inoue, Haruhiro , Boškoski, Ivo , Shimamura, Yuto , Ikebuchi, Yuichiro , Ominami, Masaki , Htet, Hein , Messmann, H, Colosso, Bianca Maria Quarta , Repici, Alessandro , Stavropoulos, Stavros N. , Bechara, Robert , Sethi, Amrita, Beyna, Torsten , Santi, Esperanza Grace , Sharma, Prateek , Eleftheriadis, Nikolas, Minami, Hitomi, Haber, Gregory , Seewald, Stefan , Shiwaku, Akio, Shiwaku, Yoshiyuki, Mori, Kensaku, Costamagna, Guido , Shimamura, Yuto , Ikebuchi, Yuichiro , Iwaya, Yugo , Htet, Hein Myat Thu , Colosso, Bianca Maria Quarta , Bechara, Robert , Kahaleh, Michel , Beyna, Torsten , Jiang, Kai, Oda, Masahiro , Familiari, Pietro , Hayee, Bu , Ho, Khek Yu , So, Jimmy Bok Yan , Bhandari, Pradeep , Grimes, Kevin L. , Maselli, Roberta , Hassan, Cesare , Fukami, Norio , Kahaleh, Michel , Sethi, Amrita , Neuhaus, Horst Ekkehard , Chiu, Philip Wai Yan , Eleftheriadis, Nikolas, Draganov, Peter V. , Mori, Kensaku , Kudo, Shin‐ei , Hasegawa, Suguru

Digestive Endoscopy | June 12, 2025 | Volume: 37 | Issue: 8 | Pages: 851-861

10.1111/den.15028 Get It

ObjectivesAchalasia is an esophageal motility disorder that impairs quality of life and is often missed (20–50%) on endoscopy. A newly developed computer‐aided detection (CAD) software has shown high accuracy for achalasia diagnosis in preclinical settings. However, its benefit in a clinical setting remains unclear.MethodsBetween February and August 2023, 83 endoscopists from 27 centers assessed 50 randomized endoscopic videos (25 achalasia, 25 nonachalasia) without and with CAD. Endoscopists assessed videos without CAD, then with CAD after 2 months. The primary end‐point was improvement in sensitivity for nonexperienced endoscopists (no endoscopic experience of achalasia). Sensitivity, specificity, and accuracy with and without CAD were compared using the McNemar test.ResultsSensitivity for diagnosing achalasia increased significantly with CAD, rising from 74.2% (95% confidence interval [CI] 72.2–76.0%) to 91.2% (95% CI 89.9–92.4%) for all readers, showing a difference of 17.1% (95% CI 15.1–19.0%). Specifically, sensitivity improved from 66.9% (95% CI 63.6–70.0%) to 91.9% (95% CI 89.9–93.6%) among nonexperienced endoscopists, resulting in a difference of 25.0% (95% CI 21.7–28.4%), and from 79.5% (95% CI 77.1–81.8%) to 90.8% (95% CI 89.0–92.3%) among experienced endoscopists (endoscopic experience of at least one achalasia case), with a difference of 11.3% (95% CI 8.9–13.6%). Accuracy and specificity improved significantly with CAD assistance, regardless of reader's experience.ConclusionCAD improves achalasia detection by 17%, confirming preclinical results. The benefit was higher for nonexperienced endoscopists. CAD assistance may lead to prompt and effective treatment, minimizing the risk of false‐negative diagnosis in clinical practice.Trial registrationThis study was registered in the University Hospital Medical Information Network Clinical Trial Registry (https://www.umin.ac.jp/ctr/) number: UMIN000053047.
Benefits and harms of optical diagnosis by artificial intelligence in colonoscopy: a multicentre cohort study
Halvorsen, Natalie , Kudo, S., Barua, Ishita , Misawa, Masashi , Gulati, Shraddha , Olabintan, Olaolu , Nilsen, J. A., Frigstad, Svein Oskar , Rastogi, A. , Holme, Øyvind , Yuichi, M., Mori, Kensaku , Hayee, Bu , East, James E. , Hassan, Cesare , Kalager, Mette , Løberg, Magnus , Haji, Amyn , Bretthauer, Michael , Yuichi, M.

Endoscopy | April 23, 2024 | Volume: 56 | Issue: S 02 | Pages: S55-S56

10.1055/s-0044-1782806 Get It

Benefits and challenges in implementation of artificial intelligence in colonoscopy: World Endoscopy Organization position statement
Hassan, Cesare , Halvorsen, Natalie , Berzin, Tyler M. , Renteln, Daniel von , Hewett, David G. , Repici, Alessandro , Ramchandani, Mohan , Khatry, Maryam Al , Yu, Honggang , Saito, Yutaka , Misawa, Masashi , Parasa, Sravanthi , Matsubayashi, Carolina Ogawa , Ogata, Haruhiko , Tajiri, Hisao, Ahmad, Omer F. , Rex, Douglas K. , Berzin, Tyler M , Hewett, David G , Wang, Pu , Saito, Yutaka , Misawa, Masashi , Matsubayashi, Carolina Ogawa , Hassan, Cesare , Mori, Yuichi , East, James E. , Byrne, Michael F. , Kudo, Shin‐ei , Wang, Pu , Pausawasdi, Nonthalee , Dekker, Evelien , Sharma, Prateek

Digestive Endoscopy | February 7, 2023 | Volume: 35 | Issue: 4 | Pages: 422-429

10.1111/den.14531 Get It

The number of artificial intelligence (AI) tools for colonoscopy on the market is increasing with supporting clinical evidence. Nevertheless, their implementation is not going smoothly for a variety of reasons, including lack of data on clinical benefits and cost‐effectiveness, lack of trustworthy guidelines, uncertain indications, and cost for implementation. To address this issue and better guide practitioners, the World Endoscopy Organization (WEO) has provided its perspective about the status of AI in colonoscopy as the position statement. WEO Position Statement: Statement 1.1: Computer‐aided detection (CADe) for colorectal polyps is likely to improve colonoscopy effectiveness by reducing adenoma miss rates and thus increase adenoma detection; Statement 1.2: In the short term, use of CADe is likely to increase health‐care costs by detecting more adenomas; Statement 1.3: In the long term, the increased cost by CADe could be balanced by savings in costs related to cancer treatment (surgery, chemotherapy, palliative care) due to CADe‐related cancer prevention; Statement 1.4: Health‐care delivery systems and authorities should evaluate the cost‐effectiveness of CADe to support its use in clinical practice; Statement 2.1: Computer‐aided diagnosis (CADx) for diminutive polyps (≤5 mm), when it has sufficient accuracy, is expected to reduce health‐care costs by reducing polypectomies, pathological examinations, or both; Statement 2.2: Health‐care delivery systems and authorities should evaluate the cost‐effectiveness of CADx to support its use in clinical practice; Statement 3: We recommend that a broad range of high‐quality cost‐effectiveness research should be undertaken to understand whether AI implementation benefits populations and societies in different health‐care systems.
Establishing key research questions for the implementation of artificial intelligence in colonoscopy: a modified Delphi method
Ahmad, Omer F. , Mori, Yuichi , Misawa, Masashi , Kudo, Toyoki , Anderson, J. , Bernal, Jorge , Bisschops, Raf , Chen, Peng‐Jen , Eelbode, Tom , Elson, Daniel S. , Gurudu, Suryakanth, Histace, Aymeric , Karnes, William E. , Repici, Alessandro , Singh, Rajvinder , Valdastri, Pietro , Wallace, Michael B. , Wang, Pu , Lovat, Laurence , Kudo, Shin-Ei , Anderson, John T , Bisschops, Raf , Chen, Peng-Jen , East, James E , Gurudu, Suryakanth R, Histace, Aymeric , Wallace, Michael B , Wang, Pu , Mori, Yuichi , Berzin, Tyler M. , Byrne, Michael F. , East, James E. , Stoyanov, Danail V.

Endoscopy | November 10, 2020 | Volume: 53 | Issue: 09 | Pages: 893-901

10.1055/a-1306-7590 Get It

Abstract Background Artificial intelligence (AI) research in colonoscopy is progressing rapidly but widespread clinical implementation is not yet a reality. We aimed to identify the top implementation research priorities. Methods An established modified Delphi approach for research priority setting was used. Fifteen international experts, including endoscopists and translational computer scientists/engineers, from nine countries participated in an online survey over 9 months. Questions related to AI implementation in colonoscopy were generated as a long-list in the first round, and then scored in two subsequent rounds to identify the top 10 research questions. Results The top 10 ranked questions were categorized into five themes. Theme 1: clinical trial design/end points (4 questions), related to optimum trial designs for polyp detection and characterization, determining the optimal end points for evaluation of AI, and demonstrating impact on interval cancer rates. Theme 2: technological developments (3 questions), including improving detection of more challenging and advanced lesions, reduction of false-positive rates, and minimizing latency. Theme 3: clinical adoption/integration (1 question), concerning the effective combination of detection and characterization into one workflow. Theme 4: data access/annotation (1 question), concerning more efficient or automated data annotation methods to reduce the burden on human experts. Theme 5: regulatory approval (1 question), related to making regulatory approval processes more efficient. Conclusions This is the first reported international research priority setting exercise for AI in colonoscopy. The study findings should be used as a framework to guide future research with key stakeholders to accelerate the clinical implementation of AI in endoscopy.
Artificial intelligence for polyp detection during colonoscopy: a systematic review and meta-analysis
Barua, Ishita , Jodal, Henriette C. , Holme, Øyvind , Misawa, Masashi , Mori, Yuichi , Vinsard, Daniela Guerrero , Mori, Yuichi , Løberg, Magnus , Kalager, Mette , Bretthauer, Michael

Endoscopy | June 17, 2020 | Volume: 53 | Issue: 03 | Pages: 277-284

10.1055/a-1201-7165 Get It

Abstract Background Artificial intelligence (AI)-based polyp detection systems are used during colonoscopy with the aim of increasing lesion detection and improving colonoscopy quality. Patients and methods: We performed a systematic review and meta-analysis of prospective trials to determine the value of AI-based polyp detection systems for detection of polyps and colorectal cancer. We performed systematic searches in MEDLINE, EMBASE, and Cochrane CENTRAL. Independent reviewers screened studies and assessed eligibility, certainty of evidence, and risk of bias. We compared colonoscopy with and without AI by calculating relative and absolute risks and mean differences for detection of polyps, adenomas, and colorectal cancer. Results Five randomized trials were eligible for analysis. Colonoscopy with AI increased adenoma detection rates (ADRs) and polyp detection rates (PDRs) compared to colonoscopy without AI (values given with 95 %CI). ADR with AI was 29.6 % (22.2 % – 37.0 %) versus 19.3 % (12.7 % – 25.9 %) without AI; relative risk (RR] 1.52 (1.31 – 1.77), with high certainty. PDR was 45.4 % (41.1 % – 49.8 %) with AI versus 30.6 % (26.5 % – 34.6 %) without AI; RR 1.48 (1.37 – 1.60), with high certainty. There was no difference in detection of advanced adenomas (mean advanced adenomas per colonoscopy 0.03 for each group, high certainty). Mean adenomas detected per colonoscopy was higher for small adenomas (≤ 5 mm) for AI versus non-AI (mean difference 0.15 [0.12 – 0.18]), but not for larger adenomas (> 5 – ≤ 10 mm, mean difference 0.03 [0.01 – 0.05]; > 10 mm, mean difference 0.01 [0.00 – 0.02]; high certainty). Data on cancer are unavailable. Conclusions AI-based polyp detection systems during colonoscopy increase detection of small nonadvanced adenomas and polyps, but not of advanced adenomas.