shunsuke omoto

shunsuke omoto

orcid

Research Focus & Metrics

Academic Career Length

14Years (2013-Present)

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

Representative Publications

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1 July 2020 in Diagnostics
Verified
Journal Article
Open access
PDF file
KYKentaro Yamao
Kentaro Yamao
Mamoru TakenakaMamoru Takenaka
Mamoru Takenaka
RIRei Ishikawa
Rei Ishikawa
AOAyana Okamoto
Ayana Okamoto
TYTomohiro Yamazaki
Tomohiro Yamazaki
Masatoshi KudoMasatoshi Kudo
Masatoshi Kudo
Background: This study aimed to evaluate and identify the specific CT findings by focusing on abnormalities in the main pancreatic duct (MPD) and pancreatic parenchyma in patients with small pancreatic cancer (PC) including carcinoma in situ (CIS). Methods: Nine CT findings indicating abnormalities of MPD and pancreatic parenchyma were selected as candidate findings for the presence of small PC ≤ 10 mm. The proportions of patients positive for each finding were compared between small PC and benign MPD stenosis groups. Interobserver agreement between two independent image reviewers was evaluated using kappa statistics. Results: The final analysis included 24 patients with small PC (including 11 CIS patients) and 28 patients with benign MPD stenosis. The proportion of patients exhibiting partial pancreatic parenchymal atrophy (PPA) corresponding to the distribution of MPD stenosis (45.8% vs. 7.1%, p < 0.01), upstream PPA arising from the site of MPD stenosis (33.3% vs. 3.6%, p = 0.01), and MPD abrupt stenosis (45.8% vs. 14.3%, p = 0.03) was significantly higher in the small PC group than in the benign MPD stenosis group. Conclusions: The presence of partial PPA, upstream PPA, and MPD abrupt stenosis on a CT image was highly suggestive of the presence of small PCs including CIS.

20 June 2017 in Digestive Endoscopy
Verified
Journal Article
Open access
PDF file
KKKen Kamata
Ken Kamata
Mamoru TakenakaMamoru Takenaka
Mamoru Takenaka
MKMasayuki Kitano
Masayuki Kitano
SOshunsuke omoto
shunsuke omoto
TMTakeshi Miyata
Takeshi Miyata
MKMasatoshi Kudo
Masatoshi Kudo
Background and Aim: Differential diagnosis of localized gallbladder lesions is challenging. The aim of the present study was to evaluate the utility of contrast‐enhanced harmonic endoscopic ultrasonography (CH‐EUS) for diagnosis of localized gallbladder lesions.Methods: One hundred and twenty‐five patients with localized gallbladder lesions were evaluated by CH‐EUS between March 2007 and February 2014. This was a single‐center retrospective study.Utilities of fundamental B‐mode EUS (FB‐EUS) and CH‐EUS in the differentiation of gallbladder lesions and sludge plug were initially compared. Thereafter, these two examinations were compared with respect to their accuracy in the diagnosis of malignant lesions. Five reviewers blinded to the clinicopathological results evaluated microcirculation patterns in the vascular and perfusion images.Results: In the differentiation between gallbladder lesions and sludge plug, FB‐EUS had a sensitivity, specificity, and accuracy of 82%, 100%, and 95%, respectively, whereas CH‐EUS had a sensitivity, specificity, and accuracy of 100%, 99%, and 99%, respectively. FB‐EUS‐based diagnosis of carcinomas based on tumor size and/or shape had a sensitivity, specificity, and accuracy of 61–87%, 71–88%, and 74–86%, respectively. Additional information regarding irregular vessel patterns in the vascular image and/or heterogeneous enhancement in the perfusion image on CH‐EUS increased the sensitivity, specificity, and accuracy for the diagnosis of carcinomas to 90%, 98%, and 96%, respectively. There was a significant difference between FB‐EUS and CH‐EUS in terms of carcinoma diagnosis.Conclusion: CH‐EUS was useful for the evaluation of localized gallbladder lesions.

5 October 2020 in Digestive Endoscopy
Verified
Journal Article
Closed access
PDF file
RIRei Ishikawa
Rei Ishikawa
KKKen Kamata
Ken Kamata
AHAkane Hara
Akane Hara
HTHidekazu Tanaka
Hidekazu Tanaka
AOAyana Okamoto
Ayana Okamoto
MKMasatoshi Kudo
Masatoshi Kudo

17 October 2023 in Digestive Endoscopy
Verified
Journal Article
Open access
TSTomotaka Saito
Tomotaka Saito
SOshunsuke omoto
shunsuke omoto
Mamoru TakenakaMamoru Takenaka
Mamoru Takenaka
MTMasahiro Tsujimae
Masahiro Tsujimae
AMAtsuhiro Masuda
Atsuhiro Masuda
FJfor the WONDERFUL study group in Japan
for the WONDERFUL study group in Japan
Objectives: No comprehensive study has examined short‐ and long‐term adverse outcomes of endoscopic ultrasound (EUS)‐guided treatment of pancreatic fluid collections (PFCs) including walled‐off necrosis (WON) and pseudocysts.Methods: In a multi‐institutional cohort of 357 patients receiving EUS‐guided treatment of PFCs (228 with WON and 129 with pseudocysts), we examined PFC type‐specific risk factors for procedure‐related adverse events (AEs), clinical failure, and recurrence. Odds ratios (ORs) and hazard ratios (HRs) with 95% confidence intervals (CIs) were computed using the logistic and Cox regression models, respectively, adjusting for potential confounders.Results: Adverse events were observed predominantly in WON, and risk factors were WON extension to the pelvis (OR 2.49; 95% CI 1.00–6.19) and endoscopic necrosectomy (OR 5.15; 95% CI 1.61–16.5). Risk factors for clinical failure in WON treatment included higher Charlson Comorbidity Index (OR for ≥3 vs. ≤2, 2.58; 95% CI 1.05–6.35), extension to the pelvis (OR 3.63; 95% CI 1.57–8.43), nonuse of a lumen‐apposing metal stent (OR 2.88; 95% CI 1.10–7.54), and percutaneous drainage (OR 3.73; 95% CI 1.27–10.9). Patients with pseudocysts extending to the paracolic gutter and the need for more than two endoscopic/percutaneous procedures had ORs for clinical failure of 5.28 (95% CI 1.10–25.3) and 5.52 (95% CI 1.61–18.9), respectively. Pseudocysts requiring the multigateway approach were associated with a high risk of recurrence (HR 4.00; 95% CI 1.11–11.6).Conclusion: The adverse outcomes at various phases of EUS‐guided PFC treatment may be predictable based on clinical parameters. Further research is warranted to optimize treatment strategies for high‐risk patients.

15 February 2018 in Cancers
Verified
Journal Article
Open access
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KMKosuke Minaga
Kosuke Minaga
Mamoru TakenakaMamoru Takenaka
Mamoru Takenaka
KKKen Kamata
Ken Kamata
TYTomoe Yoshikawa
Tomoe Yoshikawa
ANAtsushi Nakai
Atsushi Nakai
Masatoshi KudoMasatoshi Kudo
Masatoshi Kudo
The most common symptom in patients with advanced pancreatic cancer is abdominal pain. This has traditionally been treated with nonsteroidal anti-inflammatory drugs and opioid analgesics. However, these treatments result in inadequate pain control or drug-related adverse effects in some patients. An alternative pain-relief modality is celiac plexus neurolysis, in which the celiac plexus is chemically ablated. This procedure was performed percutaneously or intraoperatively until 1996, when endoscopic ultrasound (EUS)-guided celiac plexus neurolysis was first described. In this transgastric anterior approach, a neurolytic agent is injected around the celiac trunk under EUS guidance. The procedure gained popularity as a minimally invasive approach and is currently widely used to treat pancreatic cancer-associated pain. We focus on two relatively new techniques of EUS-guided neurolysis: EUS-guided celiac ganglia neurolysis and EUS-guided broad plexus neurolysis, which have been developed to improve efficacy. Although the techniques are safe and effective in general, some serious adverse events including ischemic and infectious complications have been reported as the procedure has gained widespread popularity. We summarize reported clinical outcomes of EUS-guided neurolysis in pancreatic cancer (from the PubMed and Embase databases) with a goal of providing information useful in developing strategies for pancreatic cancer-associated pain alleviation.

1 July 2016 in Ultrasonography
Verified
Journal Article
Open access
PDF file
KKKen Kamata
Ken Kamata
MKMasayuki Kitano
Masayuki Kitano
SOshunsuke omoto
shunsuke omoto
KKKumpei Kadosaka
Kumpei Kadosaka
TMTakeshi Miyata
Takeshi Miyata
Masatoshi KudoMasatoshi Kudo
Masatoshi Kudo
Endoscopic ultrasonography (EUS) is widely used to evaluate pancreaticobiliary diseases, especially pancreatic masses. EUS has a good ability to detect pancreatic masses, but it is not sufficient for the differential diagnosis of various types of lesions. In order to address the limitations of EUS, new techniques have been developed to improve the characterization of the lesions detected by EUS. EUS-guided fine needle aspiration (EUS-FNA) has been used for diagnosing pancreatic tumors. In order to improve the histological diagnostic yield, a EUS-FNA needle with a core trap has recently been developed. Contrast-enhanced harmonic EUS is a new imaging modality that uses an ultrasonographic contrast agent to visualize blood flow in fine vessels. This technique is useful in the diagnosis of pancreatic solid lesions and in confirming the presence of vascularity in mural nodules for cystic lesions. EUS elastography analyzes several different variables to measure tissue elasticity, color patterns, and strain ratio, using analytical techniques such as hue-histogram analysis, and artificial neural networks, which are useful for the diagnosis of chronic pancreatitis and pancreatic cancer.