Hironori Masuyama
Dokkyo University
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Featured researches published by Hironori Masuyama.
Gastrointestinal Endoscopy | 1999
Yasunaga Suzuki; Hideyuki Hiraishi; Kazunari Kanke; Hidetaka Watanabe; Naoyuki Ueno; Motoo Ishida; Hironori Masuyama; Akira Terano
BACKGROUND This study attempted to determine the indication for endoscopic mucosal resection with a ligating device (EMRL) and to assess the efficacy of radical (complete) resection of early gastric carcinoma and adenoma. METHODS Sixteen patients with early gastric carcinoma (17 lesions) and 21 patients with gastric adenoma (23 lesions) underwent EMRL with an endoscope with a ligating device. After epinephrine solution was injected into the submucosa, the lesions were aspirated, ligated, and resected. RESULTS Twelve of 17 early carcinomas (70.6%) and 18 of 23 adenomas (78.3%) were radically resected by EMRL. The average size of the resected specimens was 12.8 x 11.0 mm. The rate of successful radical resection by EMRL, including piecemeal resection, was 100% (15/15) for lesions located in the antrum, 80% (4/5) in the angle, 61.1% (11/18) in the body, and 0% (0/2) for lesions at the cardia. Repeat EMRL was performed successfully in cases of partial resection (n = 3). No serious complication was encountered. No recurrence of the tumors was identified in cases of radical resection during a median follow-up period of 22.8 months. CONCLUSION EMRL is suitable for the treatment of gastric tumorous lesions. For the treatment of early carcinoma, well-differentiated mucosal carcinomas smaller than 10 mm located in the distal stomach represent the best indication for EMRL.
Alimentary Pharmacology & Therapeutics | 2005
Tetsuya Nakamura; Katsuro Shirakawa; Hironori Masuyama; Hitoshi Sugaya; Hideyuki Hiraishi; Akira Terano
Background : The majority of gastro‐oesophageal reflux disease (GERD) seems to be non‐erosive reflux disease. Nonerosive reflux disease includes minimal change oesophagitis (whitish or reddish, oedematous change and erosion that is not regarded as mucosal break) and no endoscopic abnormalities.
The American Journal of Gastroenterology | 1998
Takako Sasai; Hideyuki Hiraishi; Yasunaga Suzuki; Hironori Masuyama; Motoo Ishida; Akira Terano
Several nonsurgical approaches to the treatment of postradiation proctitis have been described, but no effective conservative treatment has yet been established. As an alternative to the usual treatment, three cases of chronic postradiation proctitis with hemorrhage were successfully treated with oral administration of sucralfate, with resultant decreased bleeding in long term follow-up period. Oral sucralfate may provide a novel approach to the treatment of intractable postradiation proctitis.
Digestion | 2015
Hironori Masuyama; Naoto Yoshitake; Takako Sasai; Tetsuya Nakamura; Atsushi Masuyama; Toru Zuiki; Kentaro Kurashina; Mitsuyo Mieda; Keijiro Sunada; Hironori Yamamoto; Kazutomo Togashi; Akira Terano; Hideyuki Hiraishi
Background: The relationship between Helicobacter pylori infection and gastric cancer has been demonstrated, and the risk of gastric cancer occurrence is known to increase with the progression of atrophic changes associated with chronic gastritis. Endoscopic evaluation of the degree and extent of atrophy of the gastric mucosa is a simple and very important means of identifying a group at high risk for gastric cancer. This study aimed to clarify the carcinogenic risk in relation to the degree of atrophy. Methods: A total of 27,777 patients (272 with early gastric cancer and 135 with advanced gastric cancer) were included in this study. Endoscopically evaluated atrophy of the gastric mucosa was classified as C-0 to O-3 according to the Kimura and Takemoto classification system. Results: The cancer detection rate in relation to the degree of gastric mucosal atrophy was 0.04% (2/4,183 patients) for C-0, 0% (0/4,506) for C-1, 0.25% (9/3,660) for C-2, 0.71% (21/2,960) for C-3, 1.32% (75/5,684) for O-1, 3.70% (140/3,780) for O-2 and 5.33% (160/3,004) for O-3. As to the proportions of differentiated and undifferentiated cancers, the latter were relatively frequent in the C-0 to C-2 groups, but differentiated cancers became predominant as atrophy progressed. On the other hand, the number of both differentiated and undifferentiated cancers detected increased as gastric mucosal atrophy progressed. In addition, open-type atrophy was found in 29 (96.7%) of 30 patients with synchronous multiple gastric cancers and in all 20 patients with metachronous multiple gastric cancers. Conclusion: Endoscopic evaluation of gastric mucosal atrophy can provide a simple and reliable predictive index for both current and future carcinogenic risk.
Digestive Diseases and Sciences | 2011
Yutaka Okamoto; Hidetaka Watanabe; Keiichi Tominaga; Ryo Oki; Michiko Yamagata; Fumie Yokotsuka; Motoo Ishida; Hironori Masuyama; Hideyuki Hiraishi
AbstractsBackground/AimsNarrow band imaging (NBI) magnification analysis has entered use in clinical settings to diagnose colorectal tumors. Pit pattern analysis with magnifying endoscopy is already widely used to assess colorectal lesions and invasion depth. Our study compared diagnoses by vascular pattern analysis and pit pattern analysis with NBI magnification.MethodsWe examined 296 colorectal lesions—15 hyperplastic polyps (HP), 213 low-grade adenomas (L-Ad), 26 high-grade adenomas (H-Ad), 31 with intramucosal to scanty submucosal invasion (M-Sm-s), and 11 with massive submucosal invasion (Sm-m)—applying the system of Kudo et al. to analyze pit patterns, and the system of Tanaka et al. to analyze and classify vascular patterns by NBI into three categories: type A (hyperplasia pattern), type B (adenomatous pattern), and type C (carcinomatous pattern). Type C cases were subdivided into subtypes C1, C2, and C3. We used this system to examine histology type and invasion depth.ResultsDiagnostic sensitivity, specificity, and accuracy were 100% for both type II pit pattern HP and type A HP. Diagnostic sensitivity, specificity, and accuracy were 85.4, 94.5, and 93.2% for Vi and Vn pit pattern cancer and 95.2, 91.7, and 92.2% for type C cancer (no significant differences in sensitivity, specificity, or accuracy). Diagnostic sensitivity, specificity, and accuracy were comparable for Vi high-grade irregularity and Vn pit pattern Sm-m (90.9, 96.8, and 96.7%) and type C2/C3 Sm-m (90.1, 98.2, and 98.0%), with no significant differences in sensitivity, specificity, or accuracy.ConclusionsVascular pattern analysis by NBI magnification proved comparable to pit pattern analysis.
Photodiagnosis and Photodynamic Therapy | 2015
Tetsuya Nakamura; Takeshi Oinuma; Hidetsugu Yamagishi; Hironori Masuyama; Akira Terano
OBJECTIVE To evaluate the usefulness of a novel high-resolution magnifying videoendoscope called the XG-0001 (Fujifilm, Tokyo, Japan) that is capable of PDD and PDT in experimental and clinical situations. MATERIALS AND METHODS The fluorescences of three photosensitizers (i.e., porfimer sodium (Photofrin), protoporphyrin IX and talaporfin sodium (Laserphyrin)) were studied experimentally via excitation with a purple diode laser (VDL, wavelength 405nm). Five consecutive patients with superficial early gastric cancer not indicated for surgery or other curative endoscopic treatment due to complicated serious diseases were enrolled in this study. After close endoscopic examinations, 2mg/kg of Photofrin were intravenously injected into the patients for PDT, and 5-aminolevulinic acid (ALA; 15-20mg/kg) was orally taken for PDD. PDD using VDL and PDT using an excimer-dye laser (630nm, 4mJ, 60Hz) were performed with the XG-0001. RESULTS Photofrin and Laserphyrin had experimentally the lowest and highest fluorescence intensities, respectively. The five patients comprised four men and one woman with a mean age 75.2 year and an age range of 56-83 years. Two additional cancerous lesions were newly detected by magnifying pharmacoendoscopy. In each patient, PDD was successfully performed. PDT could also safely performed and CR was obtained in 71.4% (5/7) of the cancerous lesions in five patients, and no serious complications were encountered. CONCLUSION The XG-0001, which is based on a simultaneous videoendoscopy method that uses an RGB color chip CCD, proved extremely useful in routine use and also in PDD and PDT for gastric cancer.
Gastrointestinal Endoscopy | 1998
Kaori Sakata; Motoo Ishida; Hideyuki Hiraishi; Takako Sasai; Naomi Watanabe; Yasunaga Suzuki; Hironori Masuyama; Akira Terano
Lancet 1996;347:975. 10. Salmeron M, Desplaces N, Lavergne A, Houdart R. Campylobacter-like organisms and acute purulent gastritis. Lancet 1986;2:975-6. 11. Mitchell JD, Mitchell HM, Tobias V. Acute Helicobacter infection in an infant, associated with gastric ulceration and serological evidence of intra-familial transmission. Am J Gastroenterol 1992;87:382-6. 12. Frommer DJ, Carrick J, Lee A, Hazell S. Acute presentation of Campylobacter pylori gastritis. Am J Gastroenterol 1988; 83:1168-71. 13. Rocha GA, Queiroz DMM, Mendes EN, Barbosa AJA, Lima GF Jr, Oliveira CA. Helicobacter pylori acute gastritis: histological, endoscopical, clinical, and therapeutic features. Am J Gastroentrol 1991;86:1592-5. 14. Xiang Z, Censini S, Bayeli PF, Telford JL, Figura N, Rappuoli R, et al. Analysis of expression of CagA and VacA virulence factors in 43 strains of Helicobacter pylori reveals that clinical isolates can be divided into two major types and that CagA is not necessary for expression of the vacuolating cytotoxin. Infect Immun 1995;63:94-8. 15. Tummuru MKR, Cover TL, Blaser MJ. Cloning and expression of a high-molecular-mass major antigens of Helicobacter pylori: evidence of linkage to cytotoxin production. Infect Immun 1993;61:1799-809. 16. Fujimoto S, Marshall B, Blaser M. PCR-based restriction fragment length polymorphism typing of Helicobacter pylori. J Clin Microbiol 1994;32:331-4. 17. Katz D, Siegal HI. Erosive gastritis and acute gastrointestinal mucosal lesions. In: Glass GBJ, editor. Progress in gastroenterology. Vol 1. New York: Grune and Siralton; 1968. p. 67-96. 18. Laine L, Cominelli F, Sloane R, Casini-Raggi V, MarinSorensen M, Weinstein WM. Interaction of NSAIDs and Helicobacter pylori on gastrointestinal injury and prostaglandin production: a controlled double-blind trial. Aliment Pharmacol Ther 1995;9:127-35. 19. Graham DY, Alpert LC, Smith JL, Yoshimura HH. Iatrogenic Campylobacter pylori infection is a cause of epidemic achlorhydia. Am J Gastroenterol 1988;83:974-80. 20. Langenberg W, Rauws EAJ, Oudbier JH, Tytgat GNJ. Patient-to-patient transmission of Campylobacter pylori infection by fiberoptic gastroduodenoscopy and biopsy. J Infect Dis 1990;161:507-11. 21. Sugiyama T, Naka H, Yabana T, Awakawa T, Furuyama S, Kawauchi H, et al. Is Helicobacter pylori infection responsible for postendoscopic acute gastric mucosal lesions? Eur J Gastroenterol Hepatol 1992;4(Suppl 1):S93-6. 22. Miyaji H, Kohli Y, Azuma T, Ito S, Hirai M, Ito Y, et al. Endoscopic cross-infection with Helicobacter pylori [letter]. Lancet 1995;345:464. 23. Matysiak-Budnik T, Briet F, Heyman M, Megraud F. Laboratory-acquired Helicobacter pylori infection. Lancet 1995;346:1489-90. 24. Ghiara P, Marchetti M, Blaser MJ, Tummuru MKR, Cover TL, Segal ED, et al. Role of the Helicobacter pylori virulence factors vacuolating cytotoxin, CagA, and urease in a mouse model of disease. Infect Immun 1995;63:4154-60.
Gastroenterologia Japonica | 1989
Motoo Ishida; Hironori Masuyama
SummaryEighty cases of endoscopic injection sclerotherapy for esophageal varices were retrospectively studied to evaluate their prognoses. These cases were evaluated in terms of post-therapeutic bleeding, survival rates and causes of death. Post-therapeutic bleeding occurred in 50% of the emergency cases (26 cases), 25% of the elective cases (16 cases) and 23.7% of the prophylactic cases (38 cases). The frequency of post-therapeutic bleeding was significantly lower in cases with variceal obliteration than in cases without obliteration. An evaluation of the survival rates by the Kaplan-Meier method revealed that poor prognostic factors in sclerotherapy cases were emergency cases, Child’s C group, post-therapeutic cases with unsuccessfully obliterated varices, and cases with post-therapeutic bleeding. Concerning early death within 7 days after sclerotherapy, 4 emergency cases died from initial variceal bleeding despite sclerotherapy. Three of these 4 were hepatocellular carcinoma cases, and all 3 cases had tumor thrombi of the portal vein. We recommend prophylactic sclerotherapy from the standpoint of the prognosis after sclerotherapy. However, in the bleeding cases of hepatocellular carcinoma in Child’s C group complicated by tumor thrombi of the portal vein, overly enthusiastic application of the therapy should be avoided.
Gastrointestinal Endoscopy | 2000
Yoshihito Watanabe; Hideyuki Hiraishi; Yasunaga Suzuki; Kazuhiro Sakuma; Takako Sasai; Takeshi Oinuma; Kazunari Kanke; Hidetaka Watanabe; Motoo Ishida; Hironori Masuyama; Tadahito Shimada; Akira Terano
Background: Endoscopic variceal banding ligation (EVL) and sclerotherapy (EVS) have been used to prevent variceal hemorrhage. However, the rate of recurrence of esophageal varices after EVL or EVS is considerably high. Argon plasma coagulation (APC) is a new modality of electrosurgery to apply high frequency electric current into tissue to cause defined thermal effects. This study was conducted to determine whether APC is beneficial for eradication of residual esophageal varices after EVL or EIS. Methods: Cirrhotic patients with endoscopically assessed high-risk esophageal varices but no history of bleeding underwent EVL or EIS to reduce the risk of hemorrhage. When the size of varices was reduced 1 week later, the entire esophageal mucosae 4-5 cm proximal to the esophagogastric junction was coagulated with one session of APC in a total of 15 patients.APC was performed with the use of argon source APC300 and high frequency generator ICC 200 (ERBE, Germany). Follow-up endoscopy was performed 7 days and 1 month after the initial procedure and thereafter every 3 months, to check for recurrent/residual esophageal varices and its complications. Results: Ten to 14 days after APC, ulcerations with white coating were noted in all cases, whereas varices were completely eradicated. One month after APC, while the varices remained eradicated, coagulated esophageal mucosae became whitish and the ulcerations were nearly completely healed. During the course, no patients complained of dysphagia or retrosternal pain. Furthermore, neither development of gastric varices nor aggravation of portal hypertensive gastropathy was observed endoscopically. No serious complication such as bleeding necessitating endoscopic therapy and perforation or stricture of the esophagus was encountered. Over a maximum follow-up period of 5 months, neither recurrence of nor hemorrhage from esophageal varices was observed. Conclusions: APC ablation of residual esophageal varices in patients who have undergone prior EVL or EIS is safe and may be a novel approach to eradicate esophageal varices. It requires a long term follow-up of the eradicated varices to further evaluate its efficacy.
Digestive Endoscopy | 1994
Yoshihisa Katoh; Motoo Ishida; Hideyuki Hiraishi; Hironori Masuyama; Takashi Harada
Abstract: The incidence of back pain in patients with peptic ulcers in relation to the location of the ulceration was investigated. One hundred and seventeen patients with gastric ulcers and 35 patients with duodenal ulcers consecutively seen over the past five years were the subjects in this study. The location of the ulceration was assessed by endoscopy in all cases.