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Dive into the research topics where Senju Hashimoto is active.

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Featured researches published by Senju Hashimoto.


The American Journal of Gastroenterology | 2006

Usefulness of Contrast-Enhanced Endoscopic Ultrasonography in the Differentiation Between Malignant and Benign Lymphadenopathy *

Akira Kanamori; Yoshiki Hirooka; Akihiro Itoh; Senju Hashimoto; Hiroki Kawashima; Kazuo Hara; Hiroki Uchida; Jun Goto; Naoki Ohmiya; Yasumasa Niwa; Hidemi Goto

BACKGROUND/AIMS:Endoscopic ultrasonography (EUS) is considered the most useful diagnostic modality for regional staging; however, it is still difficult to diagnose lymph node metastasis by EUS images only. In this study, we report the usefulness of contrast-enhanced EUS (CE-EUS) in the evaluation of benign lymph nodes (BLN) or malignant lymph nodes (MLN) based on blood flow patterns.SUBJECTS AND METHODS:In the retrospective study, CE-EUS was performed in 46 patients in whom EUS revealed lymph node in the mediastinum or abdominal cavity. The subjects consisted of 22 patients with BLN and 24 patients with MLN. The lesions were examined by EUS, and the maximal and minimal diameters of lymph nodes were measured. Thereafter, the shape and internal echoes were investigated, and the findings were morphologically classified based on Catalanos report. Enhancement effects and the diagnostic capability of CE-EUS were evaluated. In the prospective study, BLNs were differentiated from MLN using the enhancement patterns on CE-EUS based on the results of the retrospective study, and the diagnostic capability was evaluated.RESULTS:In the retrospective study, there were no significant differences in the maximal diameter and maximal/minimal diameter ratio between MLN and BLN. The morphology was classified into four types. Based on the morphological classification, the sensitivity, specificity, and accuracy rate were 88.2%, 77.3%, and 82.1%, respectively. On CE-EUS, the enhancement pattern was classified into three types. The BLN lesions showed uniform enhancement (19/22). In all patients with MLN, a defect of enhancement was observed (24/24). The sensitivity, specificity, and accuracy rate of CE-EUS were 100%, 86.4%, and 92.3%, respectively. In the prospective study, the sensitivity, specificity, and accuracy rate of CE-EUS were 100%, 81.8%, and 92.0%, respectively.CONCLUSIONS:CE-EUS is useful for differentiating BLN from MLN.


Gastrointestinal Endoscopy | 1998

Contrast-enhanced endoscopic ultrasonography in gallbladder diseases

Yoshiki Hirooka; Yasuo Naitoh; Hidemi Goto; Akihiro Ito; Shinya Hayakawa; Yoshihiro Watanabe; Yoshihiro Ishiguro; Shinya Kojima; Senju Hashimoto; Tetsuo Hayakawa

BACKGROUND The purpose of this study was to investigate the usefulness of contrast-enhanced endoscopic ultrasonography in gallbladder diseases. METHODS Subjects were 38 patients including 12 with adenocarcinoma, 2 adenosquamous carcinoma, 6 cholesterol polyp, 10 cholecystitis, and 8 adenomyomatosis. After endoscopic ultrasonography, sonicated albumin was intravenously injected and the enhanced effect on images of these lesions was determined. For malignancies we compared diagnostic accuracy (T factor, TNM classification) of endoscopic ultrasonography and contrast-enhanced endoscopic ultrasonography. Vascularity as shown by contrast-enhanced endoscopic ultrasonography and angiograms was compared. RESULTS Enhancement was observed in 11 patients with adenocarcinoma but not of those with adenosquamous carcinoma or cholesterol polyp. Angiography provided hypervascular images for all cases of adenocarcinoma, but all other lesions were hypovascular. In one case of adenocarcinoma, 3 cases of adenomyomatosis, and 8 cases of cholecystitis, there was a discrepancy between contrast-enhanced endoscopic ultrasonography images and angiograms with regard to vascularity. The accuracy of depth of tumor invasion for endoscopic ultrasonography was 78.6% (11 of 14) versus 92.9% (13 of 14) for contrast-enhanced endoscopic ultrasonography. CONCLUSION Contrast-enhanced endoscopic ultrasonography is useful in the diagnosis of gallbladder lesions.


Journal of Gastroenterology and Hepatology | 2004

Comparison of image quality between electronic and mechanical radial scanning echoendoscopes in pancreatic diseases

Katsushi Niwa; Yoshiki Hirooka; Yasumasa Niwa; Akihiro Itoh; Naoki Ohmiya; Senju Hashimoto; Hideki Ishikawa; Naoto Okada; Terutomo Itoh; Hidemi Goto

Background and Aim: It is common knowledge that endoscopic ultrasonography (EUS) can accurately diagnose pancreatic diseases. Echoendoscopes for EUS are roughly classified into two categories, the mechanical radial scanning echoendoscope (MR‐ES) and the electronic linear array echoendoscope, both of which have their merits and demerits. In 2000, a newly designed echoendoscope, the electronic radial scanning echoendoscope (ER‐ES), appeared. The aim of the present study was to compare B‐mode image quality between the ER‐ES and the MR‐ES in pancreatic diseases.


Gastrointestinal Endoscopy | 2003

A comparison of image quality between tissue harmonic imaging and fundamental imaging with an electronic radial scanning echoendoscope in the diagnosis of pancreatic diseases

Hideki Ishikawa; Yoshiki Hirooka; Akihiro Itoh; Senju Hashimoto; Naoto Okada; Terutomo Itoh; Hiroki Kawashima; Hidemi Goto

BACKGROUND The availability of an electronic radial scanning echoendoscope has facilitated the clinical use of tissue harmonic imaging. This study compares the quality of US images acquired by tissue harmonic imaging during electronic radial scanning EUS to those acquired by fundamental imaging. METHODS Electronic radial scanning EUS was performed in 108 patients with pancreatic lesions (58 cystic, 50 solid). US images acquired by fundamental imaging at a frequency of 7.5 MHz were compared with those acquired by tissue harmonic imaging by using transmitting and receiving frequencies of, respectively, 4.0 and 8.0 MHz at the same scanning plane. Cystic lesions were evaluated for boundary/septum and nodules, and solid lesions, for boundary and internal structure. US images acquired by tissue harmonic imaging and fundamental imaging during electronic radial scanning EUS were compared, by using a Likert scale for the respective evaluation criteria, by two independent endoscopists. OBSERVATIONS For cystic lesions, tissue harmonic images were significantly clearer than fundamental images for visualizing boundary and septum (p < 0.0001, both reviewers) and nodules (p = 0.0003, Reviewer 1; p = 0.0007, Reviewer 2). For solid lesions, tissue harmonic images were significantly clearer than fundamental images for visualizing boundary (p = 0.0003, Reviewer 1; p < 0.0001, Reviewer 2) and internal structures (p = 0.0003, Reviewer 1; p = 0.0009, Reviewer 2). CONCLUSIONS US images acquired by tissue harmonic imaging appear to be clearer compared with those acquired by fundamental imaging.


The American Journal of Gastroenterology | 1999

An evaluation of three-dimensional ultrasonography for the measurement of gallbladder volume.

Senju Hashimoto; Hidemi Goto; Yoshiki Hirooka; Akihiro Itoh; Yoshihiro Ishiguro; Shinya Kojima; Takanori Hirai; Tetsuo Hayakawa; Yasuo Naitoh

OBJECTIVE:Various three-dimensional ultrasonography systems have been developed. We estimated the accuracy of a three-dimensional ultrasonography system for measuring gallbladder volume and compared the results to the sum-of-cylinders method.METHODS:In an in vitro study, 10 balloons of various shapes, sized 5–68 mL were scanned by real-time ultrasonography. In an in vivo study, we evaluated the gallbladder emptying of 14 healthy male volunteers after ingestion of two raw egg yolks. In both studies, volume measurement was performed by the three-dimensional ultrasonography method and the sum-of-cylinders method.RESULTS:With the three-dimensional ultrasonography method, the mean difference between the measured volume and the true volume and the limits of agreement were smaller than those of the sum-of-cylinders method. Gallbladder volumes did not differ significantly with both ultrasound methods.CONCLUSION:The three-dimensional ultrasonography method accurately determined gallbladder volumes.


Journal of Gastroenterology and Hepatology | 2003

Preclinical study of endoscopic ultrasonography with electronic radial scanning echoendoscope

Katsushi Niwa; Yoshiki Hirooka; Akihiro Itoh; Senju Hashimoto; Takanori Hirai; Kinichi Takeda; Hidemi Goto

Background: To evaluate the imaging possibility of a newly designed electronic radial scanning echoendoscope (ER‐ES).


World Journal of Gastroenterology | 2014

Factors correlating with acoustic radiation force impulse elastography in chronic hepatitis C.

Toru Nishikawa; Senju Hashimoto; Naoto Kawabe; Masao Harata; Yoshifumi Nitta; Michihito Murao; Takuji Nakano; Yuko Mizuno; Hiroaki Shimazaki; Toshiki Kan; Kazunori Nakaoka; Yuka Takagawa; Masashi Ohki; Naohiro Ichino; Keisuke Osakabe; Kentaro Yoshioka

AIM To investigate the factors other than fibrosis stage correlating with acoustic radiation force impulse (ARFI) elastograpy in chronic hepatitis C. METHODS ARFI elastograpy was performed in 108 consecutive patients with chronic hepatitis C who underwent a liver biopsy. The proportion of fibrosis area in the biopsy specimens was measured by computer-assisted morphometric image analysis. RESULTS ARFI correlated significantly with fibrosis stage (β = 0.1865, P < 0.0001) and hyaluronic acid levels (β = 0.0008, P = 0.0039) in all patients by multiple regression analysis. Fibrosis area correlated significantly with ARFI by Spearmans rank correlation test but not by multiple regression analysis. ARFI correlated significantly with body mass index (BMI) (β = -0.0334, P = 0.0001) in F 0 or F 1, with γ-glutamyltranspeptidase levels (β = 0.0048, P = 0.0012) in F 2, and with fibrosis stage (β = 0.2921, P = 0.0044) and hyaluronic acid levels (β = 0.0012, P = 0.0025) in F 3 or F 4. The ARFI cutoff value was 1.28 m/s for F ≥ 2, 1.44 m/s for F ≥ 3, and 1.73 m/s for F 4. CONCLUSION ARFI correlated with fibrosis stage and hyaluronic acid but not with inflammation. ARFI was affected by BMI, γ-glutamyltranspeptidase, and hyaluronic acid in each fibrosis stage.


Digestive Endoscopy | 2001

Linear and curved‐linear (convex) endoscopic ultrasonography: The present situation and roles in the future

Yoshiki Hirooka; Hidemi Goto; Akihiro Ito; Senju Hashimoto; Tetsuo Hayakawa

with a biopsy using endoscopy, EUS-FNAB should be used. Recently, it has become possible to obtain appropriate histologic specimens of submucosal tumors (SMT), and Mtsui et al.12 have reported that EUS-FNAB is useful for differential diagnosis of malignant and benign SMT. Furthermore, immunostaining and genetic analysis may be applied to histology samples. Thus, with the case of local recurrence, mainly developed at the outside of the intestintal tract after surgery,13 EUS-FNAB can become a useful diagnostic method for cases where biopsy with direct observation is impossible. There have been many reports regarding the utility of EUS-FNAB in diagnosing pancreatic disorders.5,7,14,15 However, when a barrier, such as the peritoneum, is penetrated between the pancreas and the digestive tract, there is the possibility that this procedure can cause the dissemination of malignant cells. Despite this, few reports mention this important issue. In one malignant case of intraductal papillary mucinous tumor (IPMT), we performed EUS-FNAB using the route from the stomach, and cancer cells were found in material from a peritoneal lavage with cytological diagnosis during surgery (Fig. 1). In this case, pseudomyxoma peritonei by peritoneal metastasis of cancer cells occurred, and this patient is currently hospitalized. It appears to be quite natural that dissemination does occur when EUS-FNAB INTRODUCTION


Journal of Gastroenterology and Hepatology | 2005

Cholecystocolonic fistula preoperatively diagnosed by endoscopic ultrasound of the colon.

Naoto Okada; Yoshiki Hirooka; Akihiro Itoh; Senju Hashimoto; Hideki Ishikawa; Terutomo Itoh; Hiroki Kawashima; Hidemi Goto

Abstract  The patient was a 58‐year‐old woman. Gallbladder stones and occult blood in feces were detected during a physical check‐up, then the patient was referred to Nagoya University Hospital. In this case the fistula was difficult to diagnosed by ultrasound and endoscopic ultrasound (EUS) of the upper intestinal tract because the gallbladder was filled with stones. Barium enema and endoscopic retrograde cholangiopancreatography did not reveal fistula. Curved‐linear array EUS of the colon showed fistula.


World Journal of Gastroenterology | 2015

Changes of shear-wave velocity by interferon-based therapy in chronic hepatitis C

Keisuke Osakabe; Naohiro Ichino; Toru Nishikawa; Hiroko Sugiyama; Miho Kato; Ai Shibata; Wakana Asada; Naoto Kawabe; Senju Hashimoto; Michihito Murao; Takuji Nakano; Hiroaki Shimazaki; Toshiki Kan; Kazunori Nakaoka; Yuka Takagawa; Masashi Ohki; Takamitsu Kurashita; Tomoki Takamura; Kentaro Yoshioka

AIM To evaluate the changes of shear-wave velocity (Vs) by acoustic radiation force impulse after treatment in chronic hepatitis C. METHODS Eighty-seven patients with chronic hepatitis C were consecutively treated with combinations of interferon (IFN) plus ribavirin (RBV). Vs value (m/s) was measured with acoustic radiation force impulse before treatment, at end of treatment (EOT), 1 year after EOT, and 2 years after EOT. RESULTS In patients with a sustained virological response (SVR) (n = 41), Vs significantly decreased at EOT [1.19 (1.07-1.37), P = 0.0004], 1 year after EOT [1.10 (1.00-1.22), P = 0.0001], and 2 years after EOT [1.05 (0.95-1.16), P < 0.0001] compared with baseline [1.27 (1.11-1.49)]. In patients with a relapse (n = 26), Vs did not significantly decrease at EOT [1.23 (1.12-1.55)], 1 year after EOT [1.20 (1.12-1.80)], and 2 years after EOT [1.41 (1.08-2.01)] compared with baseline [1.39 (1.15-1.57)]. In patients with a nonvirological response (n = 20), Vs did not significantly decrease at EOT [1.64 (1.43-2.06)], 1 year after EOT [1.66 (1.30-1.95)], and 2 years after EOT [1.61 (1.36-2.37)] compared with baseline [1.80 (1.54-2.01)]. Among genotype 1 patients, baseline Vs was significantly lower in SVR patients [1.28 (1.04-1.40)] than in non-SVR patients [1.56 (1.20-1.83)] (P = 0.0142). CONCLUSION Reduction of Vs values was shown in SVR patients after IFN-plus-RBV therapy by acoustic radiation force impulse.

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