Osamu Dohi

Dr. Osamu Dohi

Molecular Gastroenterology and Hepatology
orcid

Research Focus & Metrics

Academic Career Length

18Years (2009-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 January 2021 in Annals of Internal Medicine
Verified
Journal Article
Closed access
SOShoko Ono
Shoko Ono
KKKenro Kawada
Kenro Kawada
ODOsamu Dohi
Osamu Dohi
SKShinji Kitamura
Shinji Kitamura
TKTomoyuki Koike
Tomoyuki Koike
MKMototsugu Kato
Mototsugu Kato
Linked color imaging (LCI), a new image-enhanced endoscopy technique, allows users to recognize slight differences in mucosal color. This trial compared the performance of LCI with white light imag... Visual Linked Color Imaging for Neoplasm Detection in Upper GI Tract Linked color imaging (LCI), a new image-enhanced endoscopy technique, allows users to recognize slight differences in m... Background: Linked color imaging (LCI) is a new image-enhanced endoscopy technique that allows users to recognize slight differences in mucosal color. Objective: To compare the performance of LCI w...

19 July 2016 in Endoscopy International Open
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Journal Article
Open access
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ODOsamu Dohi
Osamu Dohi
NYNobuaki Yagi
Nobuaki Yagi
YOYuriko Onozawa
Yuriko Onozawa
RKReiko Kimura-Tsuchiya
Reiko Kimura-Tsuchiya
AMAtsushi Majima
Atsushi Majima
YIYoshito Itoh
Yoshito Itoh
Background and study aims: Linked color imaging (LCI) is a new image-enhanced endoscopy technique using a laser light source to enhance slight differences in mucosal color. The aim of this study was to compare the usefulness of LCI and conventional white light imaging (WLI) endoscopy for diagnosing Helicobacter pylori (H. pylori). Patients and methods: We retrospectively analyzed images from 60 patients examined with WLI and LCI endoscopy between October 2013 and May 2014. Thirty patients had H. pylori infections, and other thirty patients tested negative for H. pylori after eradication therapy. Four endoscopists evaluated the 2 types of images to determine which was better at facilitating a diagnosis of H. pylori infection. Results: H. pylori infection was identified with LCI by enhancing the red appearance of the fundic gland mucosa. The accuracy, sensitivity, and specificity for diagnosing H. pylori infection using WLI were 74.2 %, 81.7 %, and 66.7 %, respectively, while those for LCI were 85.8 %, 93.3 %, and 78.3 %, respectively. Thus, the accuracy and sensitivity for LCI were significantly higher than those for WLI (P = 0.002 and P = 0.011, respectively). The kappa values for the inter- and intraobserver variability among the 4 endoscopists were higher for LCI than for WLI. Conclusions: H. pylori infection can be identified by enhancing endoscopic images of the diffuse redness of the fundic gland using LCI. LCI is a novel image-enhanced endoscopy and is more useful for diagnosing H. pylori infection than is WLI.

13 June 2016 in Gastric Cancer
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Journal Article
Open access
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ODOsamu Dohi
Osamu Dohi
NYNobuaki Yagi
Nobuaki Yagi
AMAtsushi Majima
Atsushi Majima
YHYusuke Horii
Yusuke Horii
TKTomoko Kitaichi
Tomoko Kitaichi
YIYoshito Itoh
Yoshito Itoh
Background Blue laser imaging (BLI) is a new image-enhanced endoscopy technique that utilizes a laser light source developed for narrow-band light observation. The aim of this study was to evaluate the usefulness of BLI for the diagnosis of early gastric cancer. Methods This single center prospective study analyzed 530 patients. The patients were examined with both conventional endoscopy with white-light imaging (C-WLI) and magnifying endoscopy with BLI (M-BLI) at Kyoto Prefectural University of Medicine between November 2012 and March 2015. The diagnostic criteria for gastric cancer using M-BLI included an irregular microvascular pattern and/or irregular microsurface pattern, with a demarcation line according to the vessel plus surface classification system. Biopsies of the lesions were taken after C-WLI and M-BLI observation. The primary end point of this study was to compare the diagnostic performance between C-WLI and M-BLI. Results We analyzed 127 detected lesions (32 cancers and 95 non-cancers). The accuracy, sensitivity, and specificity of M-BLI diagnoses were 92.1, 93.8, and 91.6 %, respectively. On the other hand, the accuracy, sensitivity, and specificity of C-WLI diagnoses were 71.7, 46.9, and 80.0 %, respectively. Conclusions M-BLI had improved diagnostic performance for early gastric cancer compared with C-WLI. These results suggested that the diagnostic effectiveness of M-BLI is similar to that of magnifying endoscopy with narrow-band imaging (M-NBI).

14 December 2018 in Radiation Oncology
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Journal Article
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GSGen Suzuki
Gen Suzuki
Hideya YamazakiHideya Yamazaki
Hideya Yamazaki
NANorihiro Aibe
Norihiro Aibe
KMKoji Masui
Koji Masui
NSNaomi Sasaki
Naomi Sasaki
KYKei Yamada
Kei Yamada
The standard treatment for superficial esophageal cancer (SEC) involving muscularis mucosal (T1a-MM) or submucosal (T1b) invasion has been the surgical resection of the esophagus. However, esophagectomy with extended lymph node dissection is highly invasive. Recent reports have shown that endoscopic submucosal dissection (ESD) followed by chemoradiotherapy (CRT) has promising results and might become a new therapeutic approach. This retrospective study aimed to elucidate the efficacy and safety of this new treatment. Patients with clinical stage T1b tumor without apparent metastasis treated with ESD followed by CRT from 2014 to 2017 (the CRT group) were included. The outcomes on disease-free survival (DFS) of this group were compared with those of consecutive patients in a historical control group who underwent ESD followed by esophagectomy (the esophagectomy group) between 2008 and 2015. Of 32 patients analyzed, 16 were in the CRT group and 16 with similar stage cancer were in the esophagectomy group. Radiotherapy was completed in all patients, and the incidence of grade ≥ 3 nonhematologic adverse events was 6%. The 2-year overall survival rates were 100%, and locoregional control was achieved in all patients in the CRT group, and the 2-year DFS rates were 88 and 100% for the CRT and esophagectomy groups, respectively, without significant differences. Our data confirmed our new approach as being safe and effective for locoregional control and may provide a nonsurgical treatment option for patients with clinical stage T1b tumors.

13 March 2018 in Digestive Endoscopy
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Journal Article
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NINaoto Iwai
Naoto Iwai
ODOsamu Dohi
Osamu Dohi
YNYuji Naito
Yuji Naito
YIYutaka Inada
Yutaka Inada
AFAkifumi Fukui
Akifumi Fukui
YIYoshito Itoh
Yoshito Itoh

27 December 2019 in Digestive Endoscopy
Verified
Journal Article
Closed access
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ODOsamu Dohi
Osamu Dohi
Naohisa YoshidaNaohisa Yoshida
Naohisa Yoshida
YNYuji Naito
Yuji Naito
TYTakuma Yoshida
Takuma Yoshida
TITsugitaka Ishida
Tsugitaka Ishida
YIYoshito Itoh
Yoshito Itoh