112 results on '"Ryusaku Yamada"'
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2. Planned thinking and democratic personality: Karl Mannheim’s legacy for global citizenship education today
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Ryusaku Yamada
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Higher education ,business.industry ,media_common.quotation_subject ,Context (language use) ,Democracy ,Education ,Epistemology ,Interdependence ,Civility ,Personality ,Sociology ,Global citizenship ,Global citizenship education ,business ,media_common - Abstract
This article attempts to re-evaluate Karl Mannheim’s notion of “planning for freedom” within the context of contemporary global citizenship education (GCE). First, it examines Mannheim’s distinctions between “planning”, “founding”, and “administration” and analyses his notion of principia media. It argues that Mannheim conceptualised “planned thinking” as a dynamic and interdependent type of thinking necessary for grasping the whole situation of a changing world. This kind of thinking is interdisciplinary and serves to develop human capacity, through higher education, towards the cultivation of active global citizens. Second, this article examines Mannheimian conceptions of “democratic personality”, “integrative behaviour”, and “creative tolerance”, all of which are related to civility, which in turn is an indispensable aspect for GCE. The aim of this article is not to simply study Mannheim’s thoughts in the strictest sense of the word. Rather, it interprets his insights in the context of current GCE’s values and knowledge.
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- 2021
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3. The' Order' in Karl Mannheim's' Planning for Freedom': An investigation of his idea on intellectual elites in the Moot Papers ( Part 2)
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Ryusaku, Yamada
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- 2018
4. The' Order' in Karl Mannheim's' Planning for Freedom': An investigation of his idea on intellectual elites in the Moot Papers (Part 1)
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Ryusaku, Yamada
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- 2018
5. Karl Mannheim on democratic interaction: Revisiting mass society theory
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Ryusaku Yamada
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Sociology and Political Science ,media_common.quotation_subject ,05 social sciences ,050301 education ,06 humanities and the arts ,0603 philosophy, ethics and religion ,Democracy ,Epistemology ,Philosophy ,Deliberative democracy ,060302 philosophy ,Mass society ,Sociology ,Social science ,0503 education ,Law ,media_common - Abstract
This essay re-considers Karl Mannheim’s notion of democratic behaviour in the context of mass society. Although the term ‘mass society’ seems archaic, it is still the precondition of democracy today. Mannheim conceptualized mass society as irrational, disintegrating Great Society and presented the remedy of Planning for Freedom to counter the crisis of mass democracy. In his remedy Mannheim advocated social education that fosters citizens’ democratic interaction, and the keywords of his education were ‘integrative behaviour’ and ‘creative tolerance’. The similar orientation of his remedy can be found in much more contemporary critiques of deliberative democracy. Iris Marion Young’s ‘communicative democracy’ was a version of her democratic interaction in a complex, large-scale mass society. Young’s notion of ‘reasonableness’ has substantial affinity with Mannheim’s integrative behaviour, both of which require the democratic attitude of hearing the other side and the readiness to self-transform. Mass society theory has relevance for contemporary democratic theory.
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- 2016
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6. MANNHEIM, MASS SOCIETY AND DEMOCRATIC THEORY
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Ryusaku Yamada
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- 2017
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7. Reports of the second international symposium on the higher education in Japan and Taiwan held in Taipei on October 18th in 2013 under the auspices of the consortium of the universities in Osaka and Taipei
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Ryusaku, YAMADA
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Special Contribution
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- 2014
8. Balloon-Occluded Retrograde Transvenous Obliteration of Gastric Varices with Gastrorenal Shunt: Long-Term Follow-Up in 78 Patients
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Ryusaku Yamada, Toshiaki Kitayama, Kenji Nakamura, Masao Hamuro, Toshio Kaminou, Yuichi Inoue, Yukimasa Sakai, Tetsuo Arakawa, Norifumi Nishida, and Teruhisa Ninoi
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Adult ,Liver Cirrhosis ,Male ,medicine.medical_specialty ,Cirrhosis ,Esophageal and Gastric Varices ,Balloon ,Gastroenterology ,Esophageal varices ,Recurrence ,Internal medicine ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Aged ,Proportional Hazards Models ,Aged, 80 and over ,business.industry ,Esophageal disease ,Stomach ,General Medicine ,Balloon Occlusion ,Middle Aged ,Gastric varices ,medicine.disease ,Embolization, Therapeutic ,Survival Analysis ,Surgery ,Shunt (medical) ,Treatment Outcome ,medicine.anatomical_structure ,Hepatocellular carcinoma ,Female ,Gastrointestinal Hemorrhage ,business ,Follow-Up Studies - Abstract
Our aim was to evaluate the long-term clinical results after balloon-occluded retrograde transvenous obliteration (B-RTO) for gastric varices with spontaneous gastrorenal shunt.A total of 78 patients with cirrhosis and with gastric varices, successfully treated by B-RTO, were enrolled in this study. Recurrence and bleeding of gastric varices and worsening of esophageal varices were endoscopically evaluated. Univariate and multivariate analyses were used to assess the prognostic factors for worsening of esophageal varices and survival.Recurrence of gastric varices was found in two patients; the 5-year recurrence rate was 2.7%. Bleeding of gastric varices occurred in only one patient after B-RTO; the 5-year bleeding rate was 1.5%. Worsening of esophageal varices was observed in 29 patients, and the worsening rates at 1, 3, and 5 years were 27%, 58%, and 66%, respectively. These esophageal varices were endoscopically treated to prevent rupture. Multivariate analysis showed the presence of esophageal varices before B-RTO was a prognostic factor for worsening (relative risk, 4.956). At a median follow-up of 700 days (range, 137-2,339 days), the survival rates at 1, 3, and 5 years were 93%, 76%, and 54%, respectively. The prognostic factors associated with survival were presence of hepatocellular carcinoma (relative risk, 24.342) and the Child-Pugh classification (relative risk, 5.780).B-RTO is an effective method for gastric varices with gastrorenal shunt and provides lower recurrence and bleeding rates. We believe that B-RTO can become a standard treatment for gastric varices with gastrorenal shunt, although treatment of worsened esophageal varices may be necessary after B-RTO.
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- 2005
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9. The usefulness of18F-FDG PET images obtained 2 hours after intravenous injection in liver tumor
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Nozomi Ozawa, Koichi Koyama, Ryusaku Yamada, Hironobu Ochi, Terue Okamura, Shigeaki Higashiyama, and Joji Kawabe
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Male ,medicine.medical_specialty ,Carcinoma, Hepatocellular ,Time Factors ,Liver tumor ,Esophageal Neoplasms ,Sensitivity and Specificity ,18f fdg pet ,Fluorodeoxyglucose F18 ,Liver tissue ,Carcinoma ,Humans ,Medicine ,Radiology, Nuclear Medicine and imaging ,Radionuclide imaging ,Radionuclide Imaging ,neoplasms ,Aged ,Aged, 80 and over ,medicine.diagnostic_test ,business.industry ,Fdg uptake ,Liver Neoplasms ,General Medicine ,Middle Aged ,medicine.disease ,Positron emission tomography ,Hepatocellular carcinoma ,Injections, Intravenous ,Female ,Radiology ,Radiopharmaceuticals ,Colorectal Neoplasms ,business ,Nuclear medicine - Abstract
Liver tumors, especially hepatocellular carcinomas (HCCs), often exhibit no contrast with surrounding non-tumorous liver tissue in F-18-fluoro-2-deoxy-2-fluoro-D-glucose (FDG) positron emission tomography (PET) images obtained at the usual interval of one hour after intravenous FDG injection. We evaluated the usefulness of FDG PET studies of liver tumors performed 2 hours after intravenous injection.Fifteen pretherapeutic patients with 33 liver tumors were studied, including 11 patients with 18 HCCs, and 4 patients with 15 metastatic liver tumors (METAs) from 3 colorectal carcinomas and 1 esophageal carcinoma. After transmission scans, emission scans were obtained 45-55 minutes and 115-125 minutes after intravenous injection of 185-370 MBq FDG as early images and delayed FDG PET images, respectively. Visual analysis of early and delayed images was performed, and the FDG uptake in the tumor to that in nontumorous liver ratio (T/N ratio), the FDG uptake in tumor to that in soft-tissue ratio (T/S ratio) and the FDG uptake in non-tumorous liver to that in soft-tissue ratio (N/S ratio) were calculated for each image.In visual analysis, visual improvement seen in images was observed in 6 of 18 HCC lesions and all 15 META lesions. In quantitative analysis, the mean T/S ratio and T/N ratio of HCCs in early images were 4.97 and 1.90, respectively, and those in delayed images were 6.24 and 2.20, respectively. The mean T/S ratio and T/N ratio of METAs in early images were 5.97 and 2.21, respectively, and those in delayed images were 6.99 and 3.80, respectively. The T/S ratio of HCCs and T/S ratio and T/N ratio of METAs were significantly higher in delayed images than in early images. The mean N/S ratios of HCC cases were 2.58 in the early images and 2.57 in the delayed images, but the ratio showed no constant tendency in the images. All N/S ratios of META cases were decreased in delayed images, although the significance of the difference between early and delayed images in N/S ratios was not analyzed because of the small number of cases.FDG PET studies performed 2 hours after intravenous injection were useful for clear visualization of liver tumors, especially metastatic liver tumors.
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- 2002
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10. Congress of the Hellenic Society of Digestive Surgery
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Attila Oláh, Harry van Goor, J.F. de Bruïne, Preethem Suresh, Takayoshi Sekikawa, Norio Shiraishi, Hitoshi Mizuno, Ahmet Ozenc, C.M. Mouës, Hitoshi Sekido, Hideki Fujii, Ryusaku Yamada, J.H. Viersma, Abe Fingerhut, Hideki Masunari, Taichi Shuto, E.J. Spillenaar Bilgen, Erhan Hamaloglu, S.A. White, Yasuhiko Nagano, Yoshikazu Morimoto, Kishor Adyanthaya, A.R. Dennison, Hidehiko Iizuka, Shailesh V. Shrikhande, Vic Velanovich, Gary Gecelter, Yoshihiko Morimoto, Toshinori Itoh, J.H.G. Klinkenbijl, Moshe Schein, Yves N. Lopez, Bashar Fahoum, Taro Oshikiri, D. Melville, Elie Yahchouchy-Chouillard, Ajay K. Sachdev, Kazuhiro Hirohashi, Arif Ozdemir, K. van Groningen, Mikael Victorzon, M. Onwudike, Tom Mala, Syed Gardezi, Adil Ceydeli, Anstein Bergan, P. Steenvoorde, Hasan Altun, Kuniya Tanaka, Adarsh Chaudhary, Daisuke Morioka, and Akihiro Takahashi
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medicine.medical_specialty ,business.industry ,Internal medicine ,General surgery ,Digestive surgery ,Gastroenterology ,medicine ,Surgery ,business - Published
- 2002
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11. Combined balloon-occluded embolization for treatment of concurrent duodenal, gastric, and esophageal varices: A case report
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Kazunari Tominaga, Takehiro Kuga, Toshio Watanabe, Kenji Nakamura, Kazuhide Higuchi, Ai Montani, Toshiyuki Uchida, Ryusaku Yamada, Yasuhiro Fujiwara, Tetsuo Arakawa, Yoshihiko Saeki, and Masatsugu Shiba
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Male ,medicine.medical_specialty ,Duodenum ,medicine.medical_treatment ,Esophageal and Gastric Varices ,Balloon ,Varicose Veins ,Esophageal varices ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Embolization ,Esophagus ,Varix ,business.industry ,Esophageal disease ,Stomach ,Gastroenterology ,Balloon Occlusion ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,Surgery ,medicine.anatomical_structure ,business ,Varices - Published
- 2001
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12. Results of surgical and nonsurgical treatment for small-sized hepatocellular carcinomas: A retrospective and nationwide survey in Japan
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Yasuni Nakamura, Yoshio Yamaoka, Masatoshi Makuuchi, Masamichi Kojiro, Syunji Futagawa, Ryusaku Yamada, Kyoichi Inoue, Kiwamu Okita, Kenichi Kobayashi, and Shigeki Arii
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medicine.medical_specialty ,Hepatology ,business.industry ,medicine.medical_treatment ,Retrospective cohort study ,medicine.disease ,Gastroenterology ,Surgery ,Internal medicine ,Hepatocellular carcinoma ,medicine ,Carcinoma ,Embolization ,Stage (cooking) ,Percutaneous ethanol injection ,Liver cancer ,business ,Survival analysis - Abstract
Hepatic resection (HX), percutaneous ethanol injection (PEI), and transcatheter arterial embolization (TCAE) have all been used in the treatment of patients with small-sized hepatocellular carcinomas (HCCs). However, the indications for these therapeutic modalities remain unclear. Therefore, the first step to minimize the debate on these indications is to review the standard results from each treatment based on an extensive survey. The participants in this study were patients with HCCs less than 5 cm in diameter who were enrolled in The Liver Cancer Study Group of Japan. The survival rates in the HX (n = 8,010), PEI (n = 4,037), and TCAE (n = 841) groups were calculated in relation to the number of tumors and the clinical stage. In the clinical stage I cases with a solitary tumor less than 2 cm in diameter and in all clinical stages with a solitary tumor greater than 2 cm and in the clinical stage II cases with 2 tumors greater than 2 cm, the HX group showed higher survival rates than the nonsurgical groups. The HX group had a higher male/female ratio and a younger mean age than the PEI or TCAE group. The ratio of HBs antigen-positive cases/hepatitis C virus antibody-positive cases in the PEI group was lower than that in the corresponding HX group. In contrast, the PIVKA-II values in the HX group tended to be higher than in the PEI group. In conclusion, these findings will provide useful information for selection of a therapeutic modality for small-sized HCCs.
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- 2000
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13. PROTON MR SPECTROSCOPY OF THE BRAIN IN PATIENTS TREATED WITH TIPS
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M. Higashida, Masao Hamuro, Kaminou T, Kenji Nakamura, Ryusaku Yamada, and Toshiyuki Matsuoka
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Adult ,Male ,Magnetic Resonance Spectroscopy ,Glutamine ,Encephalopathy ,Glutamic Acid ,Central nervous system disease ,Liver Function Tests ,Jugular vein ,Hypertension, Portal ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Hepatic encephalopathy ,Aged ,Brain Chemistry ,Radiological and Ultrasound Technology ,medicine.diagnostic_test ,Vascular disease ,business.industry ,General Medicine ,Middle Aged ,medicine.disease ,Hepatic Encephalopathy ,Portal hypertension ,Female ,Portasystemic Shunt, Transjugular Intrahepatic ,Liver function tests ,business ,Nuclear medicine ,Inositol - Abstract
Purpose: To evaluate the utility of proton MR spectroscopy (MRS) for the early detection of hepatic encephalopathy (HE) after transjugular intrahepatic portosystemic shunting (TIPS). Material and Methods: Six patients, who underwent TIPS for treatment of portal hypertension, were examined by MRS 1 week before and 1 week after TIPS. They were simultaneously clinically examined for number connection test, blood NH3 level, liver function test and the Fischer ratio. Result: Three of 6 patients showed overt HE 1 to 5 weeks after TIPS and the other 3 patients did not show overt HE. The overt HE group showed the larger ratio of the amounts of glutamine and glutamate/myo-inositol (Glx/MI) than that of non-overt HE group ( p Conclusion: The Glx/MI ratio estimated by MRS was useful for early detection of HE after TIPS.
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- 2000
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14. Computed Tomography during Arteriography and Arterial Portography in Small Hepatocellular Carcinoma and Dysplastic Nodule: A Prospective Study
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Ryusaku Yamada, Taichi Shuto, Kenji Nakamura, Kazuhiro Hirohashi, Shinichi Mikami, Hiroaki Kinoshita, and Shoji Kubo
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Adult ,Male ,Cancer Research ,medicine.medical_specialty ,Carcinoma, Hepatocellular ,Hepatocellular carcinoma ,Article ,Adenomatous hyperplasia ,Carcinoma ,medicine ,Humans ,Prospective Studies ,cardiovascular diseases ,neoplasms ,Portography ,Diagnostic Techniques and Procedures ,Aged ,Hyperplasia ,medicine.diagnostic_test ,business.industry ,musculoskeletal, neural, and ocular physiology ,Liver Neoplasms ,Angiography ,Magnetic resonance imaging ,Digital subtraction angiography ,Middle Aged ,CT during arteriography ,HCCS ,medicine.disease ,Magnetic Resonance Imaging ,digestive system diseases ,CT during arterial portography ,Angio CT ,Oncology ,Female ,Radiology ,Tomography ,Tomography, X-Ray Computed ,business ,psychological phenomena and processes - Abstract
We studied the relationship between the findings of computed tomography during arteriography (CTA) and computed tomography during arterial portography (CTAP), and pathologic findings of 81 small nodular lesions (3 cm or less in diameter) in resected liver specimens. The 81 lesions consisted of 8 dysplastic nodule (DN) lesions, 23 well‐differentiated hepatocellular carcinomas (early HCCs) and 50 moderately or poorly differentiated HCCs (advanced HCCs). We also performed standard computed tomography (CT), digital subtraction angiography (DSA), magnetic resonance imaging (MRI), and ultrasonography, and compared sensitivities with CTA, CTAP, or combination of CTA and CTAP with other imaging methods. Forty‐four of the 50 advanced HCCs, 12 of the 23 early HCCs, and none of 8 DNs hyperattenuated with CTA and hypoattenuated with CTAP. The sensitivity for the early HCCs was significantly higher for CTA and CTAP in combination as compared with DSA or standard CT. The sensitivity for the advanced HCCs was significantly higher for CTA and CTAP in combination than with DSA. The sequential changes of the blood supply from the portal vein to the hepatic artery during the development of the HCCs were observed. Although CTA and CTAP in combination were useful for the distinction of advanced HCC from early HCC or DN, CTA and CTAP used in combination were not superior to CTA alone in the detection of such lesions.
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- 2000
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15. A case of huge gastric varices successfully treated with endoscopic injection sclerotherapy with occlusion of both supplying and draining veins with balloons
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Kenji Nakamura, Tetsuo Kuroki, Kenji Ando, Naoko Hamasaki, Yasuhiro Fujiwara, Yoshihiko Saeki, Ryusaku Yamada, Tetsuo Arakawa, Kazuhide Higuchi, Masatsugu Shiba, and Takehiro Kuga
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Male ,medicine.medical_specialty ,medicine.medical_treatment ,Oleic Acids ,Injections, Intralesional ,Esophageal and Gastric Varices ,Severity of Illness Index ,Endosonography ,Esophageal varices ,Sclerotherapy ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Endoscopy, Digestive System ,Embolization ,Aged ,Varix ,business.industry ,digestive, oral, and skin physiology ,Gastroenterology ,Balloon catheter ,Gastric varices ,medicine.disease ,Combined Modality Therapy ,Embolization, Therapeutic ,Magnetic Resonance Imaging ,Sclerosing Solutions ,digestive system diseases ,Surgery ,Radiology ,Varices ,business ,Transjugular intrahepatic portosystemic shunt ,Follow-Up Studies - Abstract
Gastric varices bleed less frequently but more severely than esophageal varices. Endoscopic treatment for gastric varices using sclerosants such as ethanol, ethanolamine oleate, and tissue adhesive agents has been reported,1-3 but no single effective method has yet been established. Other procedures for gastric varices such as surgical intervention, percutaneous transhepatic obliteration, transjugular intrahepatic portosystemic shunt (TIPS), and balloon-occluded retrograde transvenous obliteration (B-RTO) may be effective.4-9 However, these procedures cannot always be performed because patients may have poor hepatic function or a hemorrhagic diathesis and often have hepatocellular carcinoma or sometimes gastric varices without an associated gastro-renal shunt. We therefore have tried to treat such varices with endoscopic injection sclerotherapy together with percutaneous transhepatic obliteration with a balloon catheter, and, if the gastric varices have a gastro-renal shunt, with obliteration of the shunt with another balloon catheter. This procedure has the advantage that sclerosant is placed with the targeted varices, and that it can be also used to treat gastric varices safely regardless of variations in portal anatomy. In the present case, we used this procedure for giant gastric varices 15 mm in diameter with the gastro-renal shunt and obtained complete embolization of the varices with use of minimal sclerosant.
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- 2000
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16. Granulocyte-colony stimulating factor enhances anti-tumour effect of hyperthermia
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M Hosono, M Tsumura, Ryusaku Yamada, E F Sato, Masayasu Inoue, Toshifumi Nakajima, and Yoshie Takada
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Male ,Hyperthermia ,Cancer Research ,medicine.medical_specialty ,Neutrophils ,Physiology ,Ratón ,Nitric Oxide ,Superoxide dismutase ,Mice ,Anti tumour ,chemistry.chemical_compound ,Physiology (medical) ,Internal medicine ,Granulocyte Colony-Stimulating Factor ,Leukocytes ,medicine ,Animals ,chemistry.chemical_classification ,Mice, Inbred C3H ,Reactive oxygen species ,biology ,Superoxide Dismutase ,business.industry ,Hyperthermia, Induced ,Neoplasms, Experimental ,Glutathione ,medicine.disease ,Combined Modality Therapy ,Granulocyte colony-stimulating factor ,Transplantation ,Endocrinology ,chemistry ,Luminescent Measurements ,biology.protein ,Reactive Oxygen Species ,business - Abstract
The combined effect of granulocyte-colony stimulating factor (GCSF) and hyperthermia in the treatment of experimental tumours was studied to examine the possible involvement of activated granulocytes in the antitumour effect of hyperthermia. Two weeks after transplantation of SCC VII cells (1 x 10(5)) into the instep of the left leg of C3H/HeJ male mice, the mice were given subcutaneous injections of GCSF (0.2 mg/kg) for 4 days. On day 4, hyperthermia was applied locally at 43 degrees C for 40 min. Hyperthermia inhibited the tumour growth, and this effect was enhanced by pre-treating the animals with GCSF. The numbers of circulating neutrophils in control and GCSF-treated mice were 2728 +/- 517/microl and 3124 +/- 194/microl, respectively (p = 0.53). Hyperthermia increased the number of neutrophils to 4409 +/- 700/microl (p < 0.05). Hyperthermia combined with GCSF significantly increased the number of netrophils to 5479 +/- 691/microl (p < 0.01). Chemiluminescence analysis using L-012 revealed that GCSF enhanced the generation of reactive oxygen species by about 10-fold. Glutathione contents in tumours 24 h after hyperthermia decreased by about 50% in both the hyperthermia groups with or without GCSF, as compared to those in the control. The GCSF-enhanced anti-tumour activity of hyperthermia was markedly inhibited by administration of a long-acting superoxide dismutase derivative (SM-SOD). These results suggest that GCSF activates the ability to generate active oxygen species by neutrophils and, thereby, enhances the anti-tumour effect of hyperthermia.
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- 2000
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17. Thallium and FDG uptake by atelectasis with bronchogenic carcinoma
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Hideki Wanibuchi, Hironobu Ochi, Joji Kawabe, Koichi Koyama, Ryusaku Yamada, Yoshihiro Shimonishi, Miyuki Shakudo, and Terue Okamura
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Male ,Pulmonary Atelectasis ,medicine.medical_specialty ,Lung Neoplasms ,education ,chemistry.chemical_element ,Atelectasis ,Malignancy ,Fluorodeoxyglucose F18 ,medicine ,Carcinoma ,Humans ,Radiology, Nuclear Medicine and imaging ,neoplasms ,Tomography, Emission-Computed, Single-Photon ,business.industry ,Fdg uptake ,Biological Transport ,General Medicine ,Middle Aged ,medicine.disease ,High uptake ,Bronchogenic carcinoma ,carbohydrates (lipids) ,Thallium Radioisotopes ,Carcinoma, Bronchogenic ,chemistry ,Thallium ,Radiology ,Radiopharmaceuticals ,Tomography, X-Ray Computed ,business ,Tomography, Emission-Computed - Abstract
We report a case of bronchogenic carcinoma with atelectasis studied by T1-SPECT and FDG-PET. In the carcinoma, abnormally high uptake of T1 and FDG were detected, but in the region of atelectasis, an abnormally high uptake of T1 with a relatively low uptake of FDG were observed. On quantitative analyses, the T1 retention indexes of the tumor and atelectasis were 29.7 and 42.0. The mean SUVs of FDG of the tumor and the atelectasis were 8.92 and 1.28. T1-SPECT could not distinguish the atelectasis from the carcinoma. FDG-PET was superior to T1-SPECT in this case in detecting malignancy and distinguishing it from atelectasis.
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- 1999
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18. Percutaneous retroperitoneal splenorenal shunt: an experimental study in swine
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Toshio Kaminou, Ryusaku Yamada, Frederick S. Keller, Josef Rösch, Hans A. Timmermans, Shoji Sakaguchi, Barry T. Uchida, and Dusan Pavcnik
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medicine.medical_specialty ,Swine ,medicine.medical_treatment ,Venography ,Femoral vein ,Radiography, Interventional ,Hypertension, Portal ,medicine ,Animals ,Retroperitoneal space ,Radiology, Nuclear Medicine and imaging ,Retroperitoneal Space ,medicine.diagnostic_test ,business.industry ,Stent ,medicine.disease ,Surgery ,medicine.anatomical_structure ,Splenic vein ,Feasibility Studies ,Portal hypertension ,Stents ,Radiology ,Renal vein ,business ,Transjugular intrahepatic portosystemic shunt ,Splenorenal Shunt, Surgical - Abstract
To evaluate the technical possibility of creating a percutaneous retroperitoneal splenorenal shunt (PRESS) in swine as a minimally invasive treatment of portal hypertension.Five normal domestic swine underwent creation of a PRESS. A modified transjugular intrahepatic portosystemic shunt puncture set was introduced from the right femoral vein into the left renal vein. The proximal splenic vein was punctured transvenously through the retroperitoneal cavity. Noncovered metallic stents were then placed to connect both veins. The animals were sacrificed 1 hour after the procedure, after follow-up splenic venography and necropsy were performed.Puncture of the splenic vein and stent placement were successfully completed in all cases. In four of five cases, the splenic venogram revealed good flow from the splenic vein to the left renal vein through the shunt track 1 hour after creation of the PRESS, and there was no evidence of leakage. No changes in vital signs were noticed. At necropsy, a small retroperitoneal hematoma along the stent and minimal intraperitoneal bleeding were observed. The stents were found in the retroperitoneal cavity connecting both veins in all animals.Creation of a PRESS is technically possible, and further experimental studies of its efficacy are warranted.
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- 1998
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19. Fluorine-18 Fluorodeoxyglucose Positron Emission Tomography Imaging of Parotid Mass Lesions
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Terue Okamura, Hironobu Ochi, Joji Kawabe, Yoshihiro Ohashi, Ryusaku Yamada, Yoshiaki Nakai, Hirokazu Sakamoto, Miki Matsuda, and Koichi Koyama
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Adult ,Male ,Pathology ,medicine.medical_specialty ,Lesion ,Positron ,Fluorodeoxyglucose F18 ,medicine ,Humans ,Aged ,Fluorodeoxyglucose ,Fluorine-18-fluorodeoxyglucose ,medicine.diagnostic_test ,business.industry ,Parotid mass ,Magnetic resonance imaging ,General Medicine ,Middle Aged ,Magnetic Resonance Imaging ,Parotid Neoplasms ,Parotid gland ,stomatognathic diseases ,medicine.anatomical_structure ,Otorhinolaryngology ,Positron emission tomography ,Female ,Radiopharmaceuticals ,medicine.symptom ,Tomography, X-Ray Computed ,business ,Nuclear medicine ,Tomography, Emission-Computed ,medicine.drug - Abstract
Using X-ray CT or magnetic resonance imaging (MRI), fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) studies were performed in 28 patients with parotid lesions. All lesions except two showed higher accumulation of FDG than normal parotid gland. High accumulation was found in all of 5 carcinomas, all of 6 Warthin's tumors, and 8 of 12 pleomorphic adenomas, with standardized uptake values (SUVs) over 3.0. The mean SUVs of carcinomas, Warthin's tumors, and pleomorphic adenomas were 5.92 +/- 2.05, 7.03 +/- 2.49, and 4.07 +/- 1.55, respectively. On the other hand, all 5 inflammatory lesions demonstrated low accumulation, with mean SUVs of 1.66 +/- 0.89. It is thus difficult to differentiate malignant from benign parotid lesions by SUV on FDG-PET.
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- 1998
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20. Transjugular intrahepatic portosystemic shunt with silicone-covered Wallstents: results in a swine model
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Yasushi Kubota, Josef Rösch, Hirohiko Tanihata, Barry T. Uchida, Ryusaku Yamada, Dusan Pavcnik, Morio Sato, Richard R. Saxon, and Frederick S. Keller
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medicine.medical_specialty ,Surface Properties ,Swine ,medicine.medical_treatment ,Silicones ,Venography ,Inferior vena cava ,medicine ,Animals ,Radiology, Nuclear Medicine and imaging ,Derivation ,medicine.diagnostic_test ,Portal Vein ,business.industry ,Vascular disease ,Thrombosis ,medicine.disease ,Surgery ,Radiography ,medicine.vein ,Portal hypertension ,Stents ,Radiology ,Portasystemic Shunt, Transjugular Intrahepatic ,business ,Transjugular intrahepatic portosystemic shunt ,Shunt (electrical) - Abstract
To evaluate the use of impermeable silicone-covered Wallstents for transjugular intrahepatic portosystemic shunt creation.A transjugular intrahepatic portosystemic shunt was created in 14 young swine (weight, 20-32 kg) by using impermeable silicone-covered Wallstents. In eight animals, the silicone covering extended from the portal vein to the inferior vena cava. In two swine, the silicone covering ended short of the inferior vena cava, in two it ended short of the portal vein wall, and in two it ended short at each end. Follow-up transhepatic portal venography was performed weekly for 6 weeks or until the shunt was occluded. Animals were then sacrificed for gross and histologic evaluation.Only two of 14 shunts were patent after 3 weeks; both were stenosed with luminal narrowing of more than 50% in the middle of the shunt. By 6 weeks, all shunts were occluded. At histologic evaluation, a marked foreign-body reaction with superimposed thrombosis was demonstrated.In comparison with uncovered Wallstents, impermeable silicone-covered Wallstents are associated with decreased patency at transjugular intrahepatic portosystemic shunt creation. This is likely due to increased thrombogenicity and a foreign-body reaction.
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- 1997
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21. Dependency of tissue necrosis on gelatin sponge particle size after canine hepatic artery embolization
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Kazushi Kishi, Morio Sato, Tetsuo Sonomura, Norifumi Nishida, Ryusaku Yamada, and Ren J. Yang
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Surgical Sponges ,Pathology ,medicine.medical_specialty ,food.ingredient ,Necrosis ,medicine.medical_treatment ,Gelatin ,Dogs ,Hepatic Artery ,food ,Carnivora ,Animals ,Medicine ,Radiology, Nuclear Medicine and imaging ,Hepatic artery embolization ,Embolization ,Particle Size ,Pancreas ,business.industry ,Gallbladder ,Embolization, Therapeutic ,Gelatin Sponge, Absorbable ,medicine.anatomical_structure ,Liver ,Biliary tract ,Particle size ,medicine.symptom ,Cardiology and Cardiovascular Medicine ,business - Abstract
To determine the optimal size of gelatin sponge particles (GSPs) to produce maximum tumor necrosis with minimum side effects after canine hepatic artery embolization (HAE).GSPs were separated into four size ranges: A, up to 200 microns (mean 152) as Gelfoam powder; B, 200-500 microns (mean 336) as Gelfoam powder; C, 500-1000 microns (mean 649) as Spongel; and D, 1000-2000 microns (mean 1382) as Spongel. Three mongrel dogs were assigned randomly to HAE with each particle size. On day 7 after HAE, the livers were removed and subjected to pathological examination.The mean volume of liver necrosis was 11% after embolization, with particle size A, 36.3% with B, 0% with C, and 1% with D. Coagulation necrosis was found in all livers with particles of sizes A and B, and in 1 of 6 with sizes C and D. Bile duct injury was found in five of six dogs with sizes A and B and in none with sizes C and D. Gallbladder necrosis was found in one dog with size B and pancreas necrosis in one with size A.GSPs of 500 microns are considered optimally effective for tissue necrosis according to this model.
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- 1997
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22. Efficacy of Doppler ultrasonography for assessment of transjugular intrahepatic portosystemic shunt patency
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Ryusaku Yamada, Shioyama Y, Kayo Tanaka, Nobuyuki Kawai, Kazushi Kishi, Masaki Terada, Masashi Kimura, Morio Sato, and Tetsuo Sonomura
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Adult ,Male ,medicine.medical_specialty ,medicine.medical_treatment ,Esophageal and Gastric Varices ,Hypertension, Portal ,Occlusion ,Ascites ,medicine ,Humans ,Portasystemic Shunt, Surgical ,Radiology, Nuclear Medicine and imaging ,Vascular Patency ,medicine.diagnostic_test ,business.industry ,Angiography ,Ultrasonography, Doppler ,Middle Aged ,medicine.disease ,Stenosis ,Portal hypertension ,Female ,Stents ,Radiology ,medicine.symptom ,Cardiology and Cardiovascular Medicine ,business ,Varices ,Transjugular intrahepatic portosystemic shunt ,Shunt (electrical) - Abstract
To assess the efficacy of Doppler ultrasonography (US) as a noninvasive method for monitoring patency of the transjugular intrahepatic portosystemic shunt (TIPS). Twenty-nine patients who had received TIPS for bleeding esophagogastric varices and/or refractory ascites with portal hypertension underwent Doppler US studies within 2 weeks after TIPS. Further studies were performed in 15 of them at 6 months, in 9 at 1 year, and in 4 at 2 years for a total of 57 US studies. The US findings were compared with the angiographic findings obtained at the same time. In 45 of the 57 studies, shunt patency was found by Doppler US, correlating to 44 patencies and one occlusion on angiography. Doppler signal in the shunt could not be detected in 12 studies resulting in the diagnosis of shunt occlusion. This correlated with angiographic occlusion in 8 studies and patency in the remaining 4. All angiographically patent shunts that were occluded by Doppler US had various degrees of stenosis. A number of technical factors were found to be responsible for Doppler US false-positive or false-negative diagnoses, some related to the type of stent used. The Doppler US sensitivity was therefore 92%, the specificity 89%. Doppler US is a reliable noninvasive method to evaluate patency of TIPS.
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- 1996
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23. A Prospective Randomized Trial of the Preventive Effect of Pre-operative Transcatheter Arterial Embolization against Recurrence of Hepatocellular Carcinoma
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Takashi Kanematsu, Toshiharu Tsuzuki, Susumu Yamasaki, Shigeki Arii, Shingi Imaoka, Takeo Saoshiro, Munemasa Ryu, Yukio Oosaki, Hiroshi Hasegawa, Kenji Ikeda, Shouichi Kusano, Ken Takasaki, Masato Furukawa, Morito Monden, Eizo Okamoto, Youichiro Kakumoto, Ryusaku Yamada, Hideki Saitsu, Masayuki Yamamoto, and Hiroaki Kinoshita
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Adult ,Survival rate ,Cancer Research ,medicine.medical_specialty ,Carcinoma, Hepatocellular ,Randomization ,Hepatocellular carcinoma ,medicine.medical_treatment ,Gastroenterology ,Article ,Recurrence ,Internal medicine ,medicine ,Carcinoma ,Hepatectomy ,Humans ,Prospective Studies ,Embolization ,Prospective cohort study ,business.industry ,Arterial Embolization ,Liver Neoplasms ,Pre‐operative TAE ,Middle Aged ,medicine.disease ,Combined Modality Therapy ,Embolization, Therapeutic ,Survival Analysis ,Surgery ,Oncology ,business - Abstract
To clarify whether pre-operative transcatheter arterial embolization (TAE) improves survival after hepatectomy, a prospective randomized comparative study was done. Of a total of 115 registered patients having solitary hepatocellular carcinoma (HCC) 2 to 5 cm in diameter, 18 (15.7%) were excluded after randomization. As a result, 97 patients were chosen as subjects and divided into two groups: hepatectomy with (group A: n=50) and without (group B: n=47) pre-operative TAE. The period of observation of the patients who survived the surgery was between 4.0 and 6.6 years. The randomization appeared to have provided well-balanced groups of patients and the clinico-pathological characteristics of the two groups were quite similar. The necrotic part of the cancerous lesions, as confirmed by operative specimens, amounted to 74.8+/-33.4% (mean +/-SD) in group A and 6.8+/-7.2% in group B (P
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- 1996
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24. Effect of balloon occluded arterial infusion of anticancer drugs on the prognosis of cervical cancer treated with radiation therapy
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Masaaki Iwahashi, Mamoru Kawabata, Ryosuke Nakano, Kiyoshi Mitsuzane, Shunya Kitayama, Morio Sato, Koh Tsuji, and Ryusaku Yamada
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Cancer Research ,medicine.medical_specialty ,Time Factors ,medicine.medical_treatment ,Brachytherapy ,Urology ,Uterine Cervical Neoplasms ,Rectum ,Catheterization ,Actuarial Analysis ,medicine ,Humans ,Infusions, Intra-Arterial ,Radiology, Nuclear Medicine and imaging ,Stage (cooking) ,Aged ,Neoplasm Staging ,Retrospective Studies ,Cervical cancer ,Radiation ,Urinary bladder ,Radiotherapy ,business.industry ,Age Factors ,Balloon catheter ,Radiotherapy Dosage ,Prognosis ,medicine.disease ,Surgery ,Survival Rate ,Radiation therapy ,medicine.anatomical_structure ,Oncology ,Bone marrow suppression ,Female ,Particle Accelerators ,business - Abstract
Purpose : The effect of local injection of anticancer drugs by ballon catheter, i.e., balloon occuluded arterial infusion (BOAI), on the prognosis of cervical cancer treated with radiotherapy were retrospectively estimated. Methods and Materials : Sixty-five patients with cervical cancer (Stage I–IV) treated by irradiation were included in the study. Among the 65 cases, 2 were in Stage I, 13 in Stage II, 40 in Stage III, and 10 in Stage IV. Patients who received surgical resection were excluded. Thirty-nine patients received BOAI and 44 received brachytherapy. Twenty-six patients were not indicated for BOAI because of insufficient renal function, hepatic complications, hemotological complications, and refusal from the patients. Cisplatin (0.9–1.7 mg/kg), Adriamycin (0.7–0.9 mg/kg), and Pepleomycin (0.4–0.6 mg/kg) were administered simultaneously into the bilateral internal iliac arteries by BOAI. External irradiation was given by 10 MV x-ray. Total dose administered to the regional lymph nodes by the external irradiation was 48.3 ± 8.7 Gy. Radium was used at brachytherapy. The dose delivered by the brachytherapy at point A was 45.3 ± 14.9 Gy. Patients without brachytherapy received 26.1 ± 19.1 Gy of boost irradiation by the external photon beam. The survival probabilities of the patients were calculated by Kaplan-Meier method. Results : The 5-year survival rates of the Stage III patients with and without BOAI were 53 ± 13% and 24 ± 18%, respectively (p = 0.036). By multivariate analyses using Cox's proportional hazard model, stage and BOAI were selected as significant predictors of the prognosis. Transient bone marrow suppression was observed in about half of the patients with BOAI. No significant increase of the incidence of the late radiation damage by BOAI in rectum or in urinary bladder was observed. Conclusion : Balloon occuluded arterial infusion of anticancer drugs may improve the prognosis of the patients with cervical cancer without increasing the incidence of the late radiation damage. A larger scale prospective randomized study is desired.
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- 1995
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25. Predictive factors for long term prognosis after partial hepatectomy for patients with hepatocellular carcinoma in Japan.The liver cancer study group of japan
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Toshio Shikata, Takayoshi Tobe, Yasuo Endo, Eizo Okamoto, Yasuko Hiraishi, Ryuji Mizumoto, Ryusaku Yamada, Junichi Uchino, Shigeki Arii, Kyuichi Tanikawa, Masamichi Kojiro, Masao Oto, Michio Mito, and Toshiharu Tsuzuki
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Oncology ,Cancer Research ,Prognostic variable ,medicine.medical_specialty ,Cirrhosis ,Multivariate analysis ,Proportional hazards model ,business.industry ,Partial hepatectomy ,medicine.disease ,Surgery ,Internal medicine ,Hepatocellular carcinoma ,Long term survival ,medicine ,Liver cancer ,business - Abstract
Background. Great progress in the diagnosis and surgical treatment of hepatocellular carcinoma (HCC) has led to an increased number of resectable cases. Much attention has been paid to the factors affecting long term survival of patients with HCC after partial hepatectomy. Methods. Survival rates for approximately 5800 patients with HCC registered by the Liver Cancer Study Group of Japan who received partial hepatic resection from January 1, 1982 to December 31, 1989 were calculated relative to 14 clinicopathologic variables. Cox's multivariate analysis and the stepwise method then were performed to determine significant prognostic variables and to investigate the appropriate combination of these variables for predicting prognosis. Results. The use of Cox's multivariate proportional hazard model indicated that significant prognostic indicators were alpha-fetoprotein level, tumor size, number of tumors, accompanying cirrhosis, age, surgical curability, and portal involvement. The stepwise method showed that the most valuable prognostic factor was portal involvement, followed by number of tumors, alphafetoprotein level, tumor size, accompanying cirrhosis, age, and surgical curability. Furthermore, it was found that the best predictive combination of two factors was number of tumors and alpha-fetoprotein level and that the best predictive combination of three factors was the alpha-fetoprotein level, tumor size, and number of tumors. Conclusion. This extensive analysis provides information that can be used to predict the prognosis of patients with HCC after undergoing partial hepatectomy.
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- 1994
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26. Acute Toxicity of Lipiodol Infusion into the Hepatic Arteries of Dogs
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Masaki Terada, Shioyama Y, Kazushi Kishi, Tetsuo Sonomura, Norifumi Nishida, Ryusaku Yamada, and Morio Satoh
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medicine.medical_specialty ,Cholangitis ,Aspartate transaminase ,Embolism, Fat ,Gastroenterology ,Dogs ,Hepatic Artery ,Internal medicine ,Catheterization, Peripheral ,Weight Loss ,medicine ,Animals ,Infusions, Intra-Arterial ,Radiology, Nuclear Medicine and imaging ,Aspartate Aminotransferases ,Hypoalbuminemia ,Lung ,Serum Albumin ,Dose-Response Relationship, Drug ,biology ,business.industry ,Alanine Transaminase ,Iodized Oil ,General Medicine ,Alkaline Phosphatase ,medicine.disease ,Acute toxicity ,Capillaries ,medicine.anatomical_structure ,Liver ,Pancreatitis ,Alanine transaminase ,Embolism ,Acute Disease ,Lipiodol ,biology.protein ,Alkaline phosphatase ,Female ,Pulmonary Embolism ,business ,medicine.drug ,Artery - Abstract
RATIONALE AND OBJECTIVES The authors studied the acute toxicity of percutaneous transcatheter hepatic artery infusion of iodized poppy oil fatty acid ester (Lipiodol, Laboratoire Guerbet, Aulnay-sous-Bois, France). METHODS Lipiodol dosages of 0, 0.25, 0.5, 1.0, and 2.0 mL/kg were infused into the hepatic arteries of 10 beagles. Enzymatic and radiographic alterations were assessed. RESULTS After the infusion of Lipiodol, the dogs showed body weight loss and hypoalbuminemia attributable to decreased food intake, transient elevation of the aspartate transaminase and alanine transaminase, and continuous increase in alkaline phosphatase. The controls did not show any significant change. The radiographs obtained immediately after and 2 weeks after the infusion showed dose-dependent accumulation of Lipiodol in the liver. After 2 weeks, histologic examination of livers and lungs showed dose-dependent (r = .9) retention of oily droplets in sinusoids and pulmonary capillaries. Interlobar pericholangitis was found in four dogs infused with Lipiodol. Pulmonary inflammatory reaction was observed with capillary oil embolism. Oil droplets also were found in the pancreas and the brain. CONCLUSIONS Lipiodol infusion of the hepatic artery resulted in dose-dependent circulation and embolism of Lipiodol droplets via sinusoids and via pulmonary capillaries into the systemic circulation.
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- 1994
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27. Dose-Dependency of Hepatocellular Necrosis in a Canine Model of Chemoembolization
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Ryusaku Yamada, Hiroko Maeda, Morio Satoh, Renji Yan, Norifumi Nishida, Kimura M, Tetsuo Sonomura, and Kazushi Kishi
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medicine.medical_specialty ,Necrosis ,Mitomycin ,medicine.medical_treatment ,Dose dependence ,Gastroenterology ,Dogs ,Hepatic Artery ,Internal medicine ,medicine ,Animals ,Radiology, Nuclear Medicine and imaging ,Embolization ,Chemoembolization, Therapeutic ,Gelatin sponge ,Dose-Response Relationship, Drug ,business.industry ,Mitomycin C ,Gelatin Sponge, Absorbable ,Dose–response relationship ,Liver ,Doxorubicin ,Anesthesia ,Hepatocellular necrosis ,medicine.symptom ,Cardiology and Cardiovascular Medicine ,business ,Canine model - Abstract
Purpose The degree of local tissue toxicity from hepatic arterial chemoembolization relative to the dose of anticancer drugs was evaluated in 13 dogs. Materials and Methods Animals were divided into four groups. Group 1 was the control group in which embolization was performed with gelatin sponge particles only ( n = 4); group 2 animals underwent embolization with 0.4 mg/kg of Adriamycin (ADR) and 0.2 mg/kg of mitomycin C (MMC) ( n = 4); group 3, with 0.8 mg/kg of ADR and 0.4 mg/kg of MMC ( n = 2); and group 4, with 1.6 mg/kg of ADR and 0.8 mg/kg of MMC ( n = 3). Results Animals were killed 1 week after embolization, and histo-pathologic evaluation was performed. The average percentage liver necrosis in the embolized lobe was 0% in group 1, 1% in group 2, 85% in group 3, and 92% in group 4. Conclusion Hepatic arterial chemoembolization with high doses of anticancer drugs causes severe liver damage, but 0.4 mg/kg of ADR and 0.2 mg/kg of MMC is relatively safe, causing only minimal changes in this canine model.
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- 1994
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28. Current Status of Angiography and Interventional Radiology in Japan: Survey Results
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Hideo Uchida, Yasuyuki Yamashita, Mutsumasa Takahashi, Tohru Ishikawa, Ryusaku Yamada, Soji Suzuki, Kyoichi Hiramatsu, and Tsutomu Takashima
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Adult ,Male ,medicine.medical_specialty ,medicine.medical_treatment ,Survey result ,Radiology, Interventional ,Japan ,Angioplasty ,Biopsy ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Practice Patterns, Physicians' ,Abscess ,Societies, Medical ,Peripheral angiography ,medicine.diagnostic_test ,business.industry ,Data Collection ,Angiography ,Interventional radiology ,Thrombolysis ,medicine.disease ,Female ,Radiology ,Cardiology and Cardiovascular Medicine ,business - Abstract
Purpose Because the practice of interventional radiology in Japan seems very different from that in western countries, a survey was conducted to define practice patterns and the current position of radiologists in the field of vascular and interventional radiology in Japan. Materials and Methods During the spring of 1992, a questionnaire was mailed to all institutions to which members of the Japanese Society of Angiography and Interventional Radiology belong. Results For abdominal, thoracic, and peripheral angiography, more than 50% of procedures were controlled by radiologists. The majority of abdominal embolotherapy (87%) and peripheral angio-plasty (70%) procedures were performed by interventional radiologists. On the other hand, 64.3% of neurointerventions, 74% of abscess drainage, and 98% of coronary angioplasty procedures were performed by other specialists. In most institutions, embolotherapy for liver neoplasms was commonly performed by radiologists (97%). Peripheral and renal angioplasty and thrombolysis were performed by 74% of respondents, although less than 10 cases per year were encountered at 81% of institutions. Abscess drainage and biopsy were performed by radiologists in more than 50% of institutions. In other nonvascular interventional procedures, especially lithotripsy, the practice by and experiences of radiologists were very limited. Fifty-seven percent of radiology departments have beds allocated and radiologists serve as attending physicians for interventional purposes. Conclusion The practice pattern of interventional radiology in Japan is quite different from that in other countries because of differences in patients’ diseases, historical backgrounds, number of interventional radiologists, and department organization.
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- 1994
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29. Transjugular Intrahepatic Portosystemic Shunt
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Ryusaku Yamada
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medicine.medical_specialty ,business.industry ,medicine.medical_treatment ,Gastroenterology ,medicine ,Surgery ,business ,Transjugular intrahepatic portosystemic shunt - Abstract
門脈圧亢進症に対する新しい治療法として, “経皮的肝内門脈静脈短絡術” (transjugular intrahepatic portosystemic shunt: TIPS) が出現した.著者らは1992年2月より, 23例の門脈圧亢進症患老にTIPSを試み20例に成功したので, これらの初期経験を基にして, 本法の臨床的有効性や問題点について述べる.23例はすべて肝硬変Child A 5例, B4例, C14例の23例で, この内20例がTIPSに成功した.初期成功率は86%である.TIPS後, 全例に門脈圧の減少, 内視鏡所見の改善をみた.また, 10例に術前から腹水の貯溜を認めたが, TIPS後8例に腹水の消失と減少をみた.一方, 合併症として, 軽症 (grade I) の肝性脳症を20例中5例に (この内, 3例は術前より脳症があった) 認めたが, いずれも一過性で内科的治療により改善した.また, TIPS不成功3例 (中止例) の中, 1例にARDSを1例に軽微な肺炎, 1例に肝不全死を認めた.これらの症例はいずれも極めて高度の肝硬変患者であった.TIPSは門脈圧亢進症に対する有効な治療法となると考えられた.
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- 1994
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30. Self-expandable metallic stent therapy for superior vena cava syndrome: clinical observations
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Shintaro Shirai, Morio Sato, Ryusaku Yamada, Norifumi Nishida, Hisashi Kobayashi, Ren-Jie Yang, Mitsuzane K, Tetsuo Sonomura, and Kazushi Kishi
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Male ,Superior Vena Cava Syndrome ,medicine.medical_specialty ,Vena Cava, Superior ,Central Venous Pressure ,medicine.medical_treatment ,Blood Pressure ,Atrial Function, Right ,Constriction, Pathologic ,Radiology, Interventional ,Catheterization ,Constriction ,Self-expandable metallic stent ,Superior vena cava ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,cardiovascular diseases ,Aged ,Superior vena cava syndrome ,business.industry ,Central venous pressure ,Stent ,Equipment Design ,Middle Aged ,Stainless Steel ,medicine.disease ,Radiography ,Survival Rate ,Stenosis ,Balloon dilation ,Female ,Stents ,Radiology ,medicine.symptom ,Nuclear medicine ,business ,Follow-Up Studies - Abstract
PURPOSE: To study clinical and physiologic aspects of Z-stent therapy for superior vena cava (SVC) syndrome secondary to malignant disease. MATERIALS AND METHODS: Signs and symptoms of SVC syndrome were classified, graded, and scored in 11 cases. Six patients with caval pressure higher than 22 mm Hg peripheral to the stenosis underwent stent therapy. RESULTS: Immediately after Z-stent implantation into the stenotic lesion, the diameter of the constriction increased from 3.3 mm +/- 2.0 (mean +/- standard deviation) to 14.0 mm +/- 3.2, the mean caval pressure peripheral to the stenosis decreased from 26.6 mm Hg +/- 2.5 to 8.9 mm Hg +/- 0.7, and the symptom score decreased from 6.7 +/- 1.8 to 1.3 +/- 1.4. The caval pressure, lesion diameter, and symptom score correlated highly with each other. One complication--transient pulmonary edema attributable to volume overload caused by reperfusion--was observed. Mean survival exceeded 7.1 months. CONCLUSION: Stent placement could be a useful treatment for refractory...
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- 1993
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31. Effects of hepatic artery embolization with lipiodol and gelatin sponge particles on normal swine liver
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Josef Rösch, Ryusaku Yamada, Barry Uchida, Morio Sato, and Penny Hedgepeth
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medicine.medical_specialty ,Liver atrophy ,Swine ,Infarction ,Gastroenterology ,Hepatic Artery ,stomatognathic system ,Internal medicine ,medicine ,Animals ,Radiology, Nuclear Medicine and imaging ,Hepatic artery embolization ,Vein ,Gelatin sponge ,business.industry ,Iodized Oil ,medicine.disease ,Embolization, Therapeutic ,Gelatin Sponge, Absorbable ,Surgery ,Radiography ,medicine.anatomical_structure ,Coagulative necrosis ,Liver ,Lipiodol ,Cardiology and Cardiovascular Medicine ,business ,Artery ,medicine.drug - Abstract
In order to evaluate the effects of hepatic artery embolization (HAE) with Lipiodol (Lp) and gelatin sponge particles (GSP) on swine liver tissue, we embolized the hepatic arteries of 3 pigs with GSP, 9 with Lp, and 9 with Lp + GSP. None of the pigs embolized with GSP died spontaneously during the 4-week experimental period. One pig embolized with 1 ml/kg Lp and three pigs with 2 ml/kg Lp died within 2 h. Two pigs embolized with 0.5 ml/kg Lp + GSP died the following day. The portal vein pressure (PVP) and wedge hepatic vein pressure (WHVP) values before HAE, immediately after, 1 h after, and 4 weeks after HAE showed no remarkable change in the GSP group. Remarkable and temporary elevation was observed in the more than 0.2 ml/kg Lp group. Remarkable and continuous elevation was observed in the 0.2 ml/kg Lp + GSP and 0.5 ml/kg Lp + GSP groups. Gross and histological studies demonstrated no liver damage in the GSP and Lp group. Liver infarction, circular coagulation necrosis with pseudocapsule, and liver atrophy were found in the Lp + GSP group 4 weeks after HAE. The incidence of infarction, circular coagulation necrosis, and liver atrophy in the livers embolized with 0.2 ml/kg Lp + GSP and 0.5 ml/kg Lp + GSP were 67%, 100%, and 75%, respectively. In conclusion, when the hepatic artery is embolized with Lp + GSP, the volume of Lp should be limited to less than 0.1 ml/kg.
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- 1993
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32. Surgery: Diagnosis and treatment of proximal tubal obstruction by fluoroscopic transcervical Fallopian tube catheterization
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Ryosuke Nakano, Tsutako Shimamoto, Ryusaku Yamada, Morio Sato, and Masanori Sowa
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Adult ,Fallopian Tube Diseases ,medicine.medical_specialty ,animal structures ,Tubal Pregnancies ,Uterus ,Cervix Uteri ,Fallopian tube catheterization ,Catheterization ,Pregnancy ,medicine ,Humans ,Fluoroscopy ,Hysterosalpingography ,medicine.diagnostic_test ,business.industry ,Rehabilitation ,Pregnancy Outcome ,Obstetrics and Gynecology ,medicine.disease ,female genital diseases and pregnancy complications ,Surgery ,medicine.anatomical_structure ,Reproductive Medicine ,Female ,business ,Follow-Up Studies ,Fallopian tube - Abstract
The efficacy of fluoroscopic transcervical Fallopian tube catheterization in treating patients with proximal tubal obstruction was investigated. In 11 (15.9%) of the 69 patients who entered the study, patency of the proximal Fallopian tubes was shown by a pre-treatment hysterosalpingogram or an ostial selective salpingogram. Transcervical Fallopian tube catheterization attested to the success of recanalization in at least one of the obstructed tubes in 41 of our 58 patients (70.7%). Of 92 obstructed tubes, 56 (60.9%) were successfully recanalized. However, normal tubal visualization was possible in only 13 tubes (23.2%). Most of the recanalized tubes were considered to be peritubal adhesions (64.3%). Eight of 36 (22.2%) patients who had been successfully recanalized achieved pregnancies; 12 patients demonstrated normally appearing salpingograms after the procedure, and five (41.7%) had an intra-uterine pregnancy. Suspected peritubal adhesions were exhibited on post-operative salpingograms of 24 patients, one of whom had an intra-uterine pregnancy, while two had tubal pregnancies. Transcervical Fallopian tube catheterization is a simple and effective method for evaluating and treating proximal tubal obstruction. Most of the patients (70.7%) in whom recanalization was successful showed significant signs of distal tubal damage. This procedure can also be used to arrive at a prognosis regarding conception.
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- 1993
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33. Dacron-Covered Stent Therapy for Portal Vein Tumor Thrombus in Hepatocellular Carcinoma
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T. Sonomura, Morio Sato, Norifumi Nishida, Kazushi Kishi, Ryusaku Yamada, and Kiyoshi Mitsuzane
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Male ,medicine.medical_specialty ,Carcinoma, Hepatocellular ,Percutaneous ,medicine.medical_treatment ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Carcinoma ,Humans ,Radiology, Nuclear Medicine and imaging ,cardiovascular diseases ,Radiological and Ultrasound Technology ,medicine.diagnostic_test ,Polyethylene Terephthalates ,Portal Vein ,business.industry ,Liver Neoplasms ,Stent ,Thrombosis ,Equipment Design ,General Medicine ,Blood flow ,Middle Aged ,equipment and supplies ,medicine.disease ,Surgery ,Stenosis ,surgical procedures, operative ,030220 oncology & carcinogenesis ,Angiography ,cardiovascular system ,Portal hypertension ,Stents ,Radiology ,business - Abstract
A tumor thrombus of the portal vein is refractory to therapy and constitutes a serious prognostic factor in hepatocellular carcinoma. For the purpose of treating portal vein tumor thrombus by restoring the blood flow and preventing recurrent ingrowth of tumor, we devised a metallic stent partially covered with a Dacron mesh sheet, and a coaxial percutaneous delivery system. One half of the wall of a Gianturco Z-stent was covered with a sheet of 0.25-mm-thick Dacron mesh, fixed to the stent wall with nylon threads. The covered stent was implanted in a patient with severe main portal vein stenosis due to tumor thrombus protruding from the left portal vein branch. Immediately after stent placement the tumor stenosis was effectively dilated, the portal blood flow restored, and the portal hypertension relieved. CT and angiography after 8 months still showed complete portal vein patency. Intrahepatic tumor dissemination or other complications were not observed. Intraportal placement of a covered metallic stent appears to be an efficacious therapy of major portal tumor thrombi.
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- 1993
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34. Percutaneous Transluminal Angioplasty for Segmental Obstruction of the Hepatic Inferior Vena Cava
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Ryusaku Yamada, T. Sonomura, Shioyama Y, Shozo Nomura, Morio Sato, Masaki Terada, Ren-Jie Yang, Ko Tsuji, and Kazushi Kishi
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medicine.medical_specialty ,Percutaneous ,medicine.vein ,business.industry ,medicine ,Radiology, Nuclear Medicine and imaging ,Radiology ,Cardiology and Cardiovascular Medicine ,Transluminal Angioplasty ,business ,Inferior vena cava ,Surgery - Published
- 1993
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35. Directly injective chemotherapy combined with transcatheter arterial embolization in the treatment for the liver cancers
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Kayo Tanaka, Nobuyuki Kawai, Ryusaku Yamada, Morio Sato, and Masashi Kimura
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medicine.medical_specialty ,Chemotherapy ,business.industry ,medicine.medical_treatment ,Arterial Embolization ,Pharmaceutical Science ,Medicine ,Radiology ,business - Published
- 1993
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36. Clinical and immunological evaluation of intraoperative radiation therapy for patients with unresectable pancreatic cancer
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Kohei Noguchi, Masakazu Sasaki, Masaji Tani, Hiroki Yamaue, Ryusaku Yamada, Takuya Tsunoda, Hideo Kashiwagi, Yozo Aoki, Hiroshi Tanimura, Makoto Iwahashi, and M Tamai
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Male ,medicine.medical_specialty ,Pancreatic disease ,medicine.medical_treatment ,Lymphocyte ,Urology ,Natural killer cell ,medicine ,Humans ,Antigens, Tumor-Associated, Carbohydrate ,Killer Cells, Lymphokine-Activated ,Intraoperative radiation therapy ,Aged ,Lymphokine-activated killer cell ,business.industry ,Radiotherapy Dosage ,General Medicine ,Middle Aged ,medicine.disease ,Neoplasm Proteins ,Surgery ,Killer Cells, Natural ,Pancreatic Neoplasms ,Survival Rate ,Radiation therapy ,medicine.anatomical_structure ,Cytokine ,Oncology ,Female ,Pancreas ,business - Abstract
The clinical efficacy of intraoperative radiation therapy (IORT) and the changes of immunological parameters were investigated. Nine patients with unresectable pancreatic cancer were treated with IORT (2,500-3,500 cGy) and the changes of various immunological parameters were compared with those in 11 patients with advanced cancer who received external beam irradiation therapy (XRT), 2,500-3,500 cGy. After IORT, 71% of patients obtained pain relief, two of the nine patients showed a partial response, and the serum CA 19-9 level decreased in six patients. However, the median survival was only 210 days. Natural killer activity, lymphokine-activated killer activity, and interferon gamma-activated killer activity were not inhibited by IORT, and phytohemagglutinin-induced blastogenesis was actually augmented after IORT, whereas all these parameters were inhibited by XRT. Thus, it is suggested that IORT may augment or at least stabilize systemic antitumor immunity.
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- 1992
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37. Study on Time Course of PIVKA-II and AFP levels after hepatic artery embolization for hepatocellular carcinomas. Relation between time course in PIVKA-II and AFP levels and tumor necrosis
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Morio Sato, Ryusaku Yamada, Kazuishi Kishi, Kiyoshi Mitsuzane, and Tetsuo Sonomura
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medicine.medical_specialty ,Hepatology ,business.industry ,Internal medicine ,Time course ,medicine ,Tumor necrosis factor alpha ,Hepatic artery embolization ,Radiology ,business ,Gastroenterology - Published
- 1992
- Full Text
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38. A triple coaxial catheter system for subselective visceral artery catheterization and embolization: Preliminary clinical experience
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Kenji Nakamura, Kaminou T, Toshiyuki Matsuoka, Sumio Takashima, Ryusaku Yamada, Seishou Hayashi, and Ryoichi Matsuo
- Subjects
medicine.medical_specialty ,Visceral artery ,medicine.diagnostic_test ,business.industry ,medicine.medical_treatment ,Liver Neoplasms ,Ultrasound ,Angiography ,Equipment Design ,urologic and male genital diseases ,Embolization, Therapeutic ,female genital diseases and pregnancy complications ,Catheter ,Hepatic Artery ,Hepatic angiography ,Coaxial catheter ,Humans ,Medicine ,Radiology, Nuclear Medicine and imaging ,Radiology ,Embolization ,Cardiology and Cardiovascular Medicine ,business ,Aged - Abstract
We developed a triple coaxial catheter system (TCCS) which consists of a 6.1 Fr outer, a 4.1 Fr intermediate, and a 3.0 Fr inner catheter, all coated with a lubricant. The TCCS was used in seven patients with hepatic tumors, after several attempts to access a targeted vessel with conventional catheters and guidewires failed to reach the targeted vessel. No complications were encountered with the use of this system. TCCS may be a useful device for selective abdominal arteriography.
- Published
- 1998
- Full Text
- View/download PDF
39. Selective balloon-occluded retrograde transvenous obliteration of gastric varix with preservation of major portacaval shunt
- Author
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Kenji Nakamura, Ryusaku Yamada, Masahiro Tokunaga, Yukimasa Sakai, Toshiaki Kitayama, Yuichi Inoue, Masao Hamuro, Teruhisa Ninoi, and Norifumi Nishida
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Male ,medicine.medical_specialty ,Varix ,business.industry ,Portacaval Shunt, Surgical ,medicine.medical_treatment ,Portal venous pressure ,Portacaval shunt ,General Medicine ,Gastric varices ,Balloon Occlusion ,medicine.disease ,Esophageal and Gastric Varices ,Shunt (medical) ,Surgery ,Esophageal varices ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Radiology ,Embolization ,Varices ,business ,Aged - Abstract
1All authors: Department of Radiology, Osaka City University Graduate School of Medicine, 1-4-3, Asahimachi, Abeno-bu, Osaka, Japan 545-8585. Address correspondence to N. Nishida (norifumin@med.osakacu.ac.jp). alloon-occluded retrograde transvenous obliteration (B-RTO) has been performed instead of endoscopic and surgical treatment in the management of gastric varix. The procedure is indicated for gastric varix with a major portacaval shunt, such as a gastrorenal shunt or a shunt involving the left inferior phrenic vein, and usually obliterates the gastric varix and the connecting major portacaval shunt. BRTO is safe, feasible, and effective in the treatment of patients with gastric varix; however, aggravation of esophageal varix is an important complication caused by increasing portal pressure [1–3]. We report the first case, to our knowledge, of selective B-RTO with preservation of the major portacaval shunt. MDCT during splenic and superior mesenteric arterial portography was useful for confirming the morphologic features and developing a precise therapeutic plan.
- Published
- 2006
40. [Clinical study of porous gelatin sphere (YM 670) in transcatheter arterial embolization]
- Author
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Ryusaku, Yamada, Satoshi, Sawada, Hideo, Uchida, Tatsuo, Kumazaki, Kyoichi, Hiramatsu, Hiromasa, Ishii, Norio, Nakao, Hironobu, Nakamura, and Tetsuo, Taguchi
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Adult ,Male ,Carcinoma, Hepatocellular ,Hepatic Artery ,Liver Neoplasms ,Gelatin ,Humans ,Female ,Middle Aged ,Embolization, Therapeutic ,Aged - Abstract
A clinical study on the use of porous gelatin particles(sterile gelatin embolization material, YM 670, Gelpart) in transcatheter arterial embolization (TAE) was performed in patients with hepatocellular carcinoma, and the efficacy (embolization,anti-tumor effect, recanalization and operationality) and safety (tolerability) were studied. An additive agent comprising porous gelatin particles and low osmolarity contrast media was administered peripherally through a catheter into the hepatic artery proper of 63 patients with hepatocellular carcinoma. Good hepatic arterial embolization was confirmed in all cases (embolization: 100%), and a tumor necrosis effect was obtained in most cases (35/62 patients, 56.5%). Moreover, operationality was assessed as "highly easy to use" or "easy to use" in all cases. Frequencies of adverse events in which a relationship to TAE was not excluded and abnormalities of clinical laboratory data were high at 71.4% and 9 8.4%, respectively. The most common adverse reactions were pyrexia, abdominal pain, queasiness and blood pressure increase;abnormalities in clinical laboratory data included hepatic function with increased AST (GOT), increased ALT (GPT), decreased cholinesterase, increased LDH and increased total bilirubin. These adverse reactions and abnormalities in clinical laboratory data, however, were transient and attributed to the TAE procedure itself, and no adverse reactions related to YM 670 as an embolic material were observed. In addition, with regard to tolerability (safety), the treatment was assessed as suitable for use in all the present cases.
- Published
- 2005
41. The influence of radiofrequency ablation on hepatic vessels in porcine liver
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Kimihiko, Sato, Kenji, Nakamura, Masao, Hamuro, Yukimasa, Sakai, Norifumi, Nishida, Ryusaku, Yamada, Yoshihiro, Ikura, Makiko, Ueda, and Yuichi, Inoue
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Liver ,Portal Vein ,Swine ,Catheter Ablation ,Animals ,Endothelium, Vascular ,Hepatic Veins ,Tomography, X-Ray Computed ,Vascular Patency - Abstract
The objective of this study was to clarify the influence of radiofrequency ablation on the portal and hepatic vein.Hepatic radiofrequency ablation was performed on 18 swine (mean weight, 22 kg). The livers were removed immediately, 1 week or 3 weeks following ablation. Vessel patency and diameter were determined by computed tomography, and the severity of endothelial injuries was determined histopathologically.The patency rate for portal and hepatic veins with diameters less than 3.0 mm decreased sequentially. At three weeks following ablation, the patency rate for vessels with diameters more than 3.0 mm was significantly higher (P0.05) compared to those with diameters less than 2.0 mm. In portal and hepatic veins contiguous to ablated hepatic parenchyma, the endothelium with intimal thickening was found at 1 to 3 weeks following ablation, although its detection rate was decreased until 3 weeks.The portal and hepatic vein with diameters more than 3.0 mm in radiofrequency lesions maintained high patency. The endothelium seems to play an important role for maintaining vessels patency and the distal hepatic tissue following ablation. We believe that this maintained vascular patency may be the advantage of radiofrequency ablation over the PEIT.
- Published
- 2005
42. Post-TIPS hepatic encephalopathy treated by occlusion balloon-assisted retrograde embolization of a coexisting spontaneous splenorenal shunt
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Kiyoshi Matsueda, Koushi Horihata, Ryusaku Yamada, Morio Sato, Kazushi Kishi, Norifumi Nishida, Masashi Kimura, Masaki Terada, and Shioyama Y
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Male ,medicine.medical_specialty ,Cirrhosis ,Fistula ,medicine.medical_treatment ,Encephalopathy ,Vena Cava, Inferior ,Esophageal and Gastric Varices ,Renal Veins ,Catheterization ,Esophageal varices ,Recurrence ,Jugular vein ,Hypertension, Portal ,Humans ,Portasystemic Shunt, Surgical ,Medicine ,Radiology, Nuclear Medicine and imaging ,Embolization ,Hepatic encephalopathy ,business.industry ,Phlebography ,Middle Aged ,medicine.disease ,Embolization, Therapeutic ,Surgery ,Splenic Vein ,Hepatic Encephalopathy ,Portal hypertension ,Radiology ,Cardiology and Cardiovascular Medicine ,business ,Transjugular intrahepatic portosystemic shunt - Abstract
A 51-year-old man with posthepatitis cirrhosis underwent a transjugular intrahepatic portosystemic shunt (TIPS) for bleeding of recurrent esophageal varices. The patient had a coexisting, spontaneous, splenorenal shunt. He subsequently developed hepatic encephalopathy, presumably due to excessive portosystemic shunting. Since medical management resulted in no significant improvement, the splenorenal shunt was embolized from the jugular vein approach via renal vein access during temporary balloon occlusion. Within a few days, the patient's hepatic encephalopathy resolved. Twelve months later the patient showed no recurrence of encephalopathy and had maintained a patent TIPS.
- Published
- 1996
- Full Text
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43. TIPS versus transcatheter sclerotherapy for gastric varices
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Norifumi Nishida, Masao Hamuro, Teruhisa Ninoi, Ryusaku Yamada, Tetsuo Arakawa, Yukimasa Sakai, Kenji Nakamura, Toshiaki Kitayama, Toshio Kaminou, and Yuichi Inoue
- Subjects
Male ,medicine.medical_specialty ,Prognostic factor ,Variceal bleeding ,medicine.medical_treatment ,Esophageal and Gastric Varices ,Gastroenterology ,Statistics, Nonparametric ,Liver Function Tests ,Risk Factors ,Internal medicine ,Sclerotherapy ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Retrospective Studies ,Analysis of Variance ,Chi-Square Distribution ,business.industry ,Stomach ,General Medicine ,Gastric varices ,medicine.disease ,Surgery ,Survival Rate ,medicine.anatomical_structure ,Treatment Outcome ,Hepatocellular carcinoma ,Multivariate Analysis ,Female ,Liver function ,Portasystemic Shunt, Transjugular Intrahepatic ,business ,Transjugular intrahepatic portosystemic shunt - Abstract
The purpose of our study was to compare the efficacy and long-term results of transjugular intrahepatic portosystemic shunt (TIPS) with those of transcatheter sclerotherapy for the treatment of gastric varices.A total of 139 cirrhotic patients with gastric varices underwent endovascular treatment. Of the 139 patients, 104 without hepatocellular carcinoma were enrolled; 27 patients were treated with TIPS, and 77 patients with transcatheter sclerotherapy. Bleeding of gastric varices and survival rates were compared between the TIPS and transcatheter sclerotherapy groups. Multivariate analysis was used to identify the prognostic factors for gastric variceal bleeding and survival. Changes in liver function were evaluated in each group.The cumulative gastric variceal bleeding rate at 1 year was 20% in the TIPS group and 2% in the transcatheter sclerotherapy group (p0.01). The prognostic factor associated with gastric variceal bleeding was the treatment method. The cumulative survival rates at 1, 3, and 5 years were, respectively, 81%, 64%, and 40% in the TIPS group and 96%, 83%, and 76% in the transcatheter sclerotherapy group (p0.01). The prognostic factors for survival were the treatment method and the Child-Pugh classification of liver disease. For patients categorized in Child-Pugh class A, the survival rate was higher in the transcatheter sclerotherapy group than in the TIPS group (p0.01). For patients in Child-Pugh classes B and C, no significant difference was seen between the two groups. Liver function tended to improve in the transcatheter sclerotherapy group.Transcatheter sclerotherapy may provide better control of gastric variceal bleeding than TIPS. Transcatheter sclerotherapy may contribute to a higher survival rate than TIPS in patients with Child-Pugh class A disease.
- Published
- 2004
44. Use of FDG-microPET for detection of small nodules in a rabbit model of pulmonary metastatic cancer
- Author
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Satoko Kondo, Yasuhiro Wada, Ryusaku Yamada, Yoshie Takada, Yasuyoshi Watanabe, Kentaro Ishii, Masako Hosono, Terue Okamura, Haruyuki Fukuda, Akira Matsumura, Yuichi Inoue, and Mari Tashiro
- Subjects
Light nucleus ,Validation study ,Lung Neoplasms ,Sensitivity and Specificity ,Fluorodeoxyglucose F18 ,Cell Line, Tumor ,Cat scanning ,Medicine ,Animals ,Radiology, Nuclear Medicine and imaging ,medicine.diagnostic_test ,business.industry ,Carcinoma ,Cancer ,Reproducibility of Results ,Solitary Pulmonary Nodule ,General Medicine ,medicine.disease ,carbohydrates (lipids) ,Radiography ,Disease Models, Animal ,Rabbit model ,Lung tumor ,Rabbits ,Radiopharmaceuticals ,business ,Nuclear medicine ,Emission computed tomography ,Tomography, Emission-Computed - Abstract
The performance of microPET using 18F-FDG was evaluated in a rabbit model of hematogenous pulmonary metastatic cancer.A total of 15 Japanese white rabbits and VX-2 carcinoma were used in this study. In the microPET study, tumor-bearing rabbits were administered intravenously 74 MBq of 18F-FDG, and 30 min later, the emission data were acquired for 60 min. The transmission scans were performed with a 68Ge/68Ga external point source. To augment the anatomical information, we performed multi-detector row computed tomography (MDCT) in the combination with MDCT and microPET on 10 rabbits. The other 5 rabbits were followed once a week for 5 weeks only by microPET. Tumor/muscle (T/M) ratios were used for quantitative evaluation in this study.Multiple pulmonary nodules were detected by MDCT and microPET starting 14 days after the tumor injection. The high-uptake lesions in the lung detected by microPET corresponded well to the tumors detected by MDCT. The smallest nodule detected by microPET was ca. 1.5 mm in diameter. Overall, 87 nodules were detected by MDCT and the ratios of lesions detected by microPET to those by MDCT were 35.3%, 77.5%, and 90% for tumors equal to or smaller than 2 mm, 2-4 mm, and 4-6 mm in diameter, respectively. The respective T/M ratios were 2.41 +/- 0.41, 2.93 +/- 0.55, and 3.34 +/- 0.71. The T/M ratio increased with tumor size, but it was similar in each tumor size category. In the 35-day follow-up protocol, it was possible to follow sequentially the same tumor by the microPET.By FDG-microPET, it is possible to evaluate tumors larger than 2 mm in diameter and to follow the growth of individual tumors. Our results also suggest that the rabbit model of VX-2 pulmonary metastasis is a stable experimental model for evaluation using FDG. Monitoring of the therapeutic effects of anticancer drugs and radiation therapy could be tried by using this model and microPET.
- Published
- 2004
45. Evaluation of 18F-FDG PET with bladder irrigation in patients with uterine and ovarian tumors
- Author
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Koichi, Koyama, Terue, Okamura, Joji, Kawabe, Nozomi, Ozawa, Kenzi, Torii, Naohiko, Umesaki, Masato, Miyama, Hironobu, Ochi, and Ryusaku, Yamada
- Subjects
Adult ,Aged, 80 and over ,Ovarian Neoplasms ,Carcinoma ,Urinary Bladder ,Uterine Cervical Neoplasms ,Middle Aged ,Diagnosis, Differential ,Fluorodeoxyglucose F18 ,Uterine Neoplasms ,Humans ,Female ,Radiopharmaceuticals ,Artifacts ,Therapeutic Irrigation ,Aged ,Tomography, Emission-Computed - Abstract
The purpose of this study was to evaluate PET using (18)F-FDG for gynecologic lesions with continuous bladder irrigation to eliminate artifacts from the (18)F-FDG activity in the bladder.Forty-one patients were studied. They had 23 cervical uterine lesions (15 cases of cancer, 5 recurrences, 3 nonrecurrences); 8 cases of uterine corpus cancer, including 2 recurrences; and 10 ovarian masses (6 malignant, 4 nonmalignant). All cases of cancer were histologically proven; however, 2 cases of nonrecurrent uterine cervical carcinomas were diagnosed by clinical course. Continuous bladder irrigation was performed 35-55 min after intravenous administration of 185-370 MBq (18)F-FDG, and an emission scan was obtained 40-55 min after intravenous administration. Standardized uptake value (SUV) was used to estimate the degree of (18)F-FDG uptake quantitatively.After bladder irrigation, the (18)F-FDG activity in the urinary tract was eliminated in 33 patients, so that detection of tumor (18)F-FDG accumulation was easy. Two patients showed residual activity in the urinary bladder, and 6 patients showed activity in the ureter. An artifact was seen in 1 patient with residual activity in the urinary bladder caused by insufficient irrigation. However, these residual activities had no influence on detecting (18)F-FDG accumulation in tumor. The mean (+/-SD) of SUVs of malignant lesions was 6.04 +/- 3.22, that of nonmalignant lesions was 1.71 +/- 1.12, and the difference was significant (P = 0.0002). SUVs of all malignant lesions were greater than 2.0, and SUVs of all nonmalignant lesions, except the 1 case of ovarian fibroma, were less than 2.0.(18)F-FDG PET with continuous bladder irrigation is useful for eliminating (18)F-FDG activity in the bladder and for differentiating between malignant and nonmalignant uterine or ovarian masses.
- Published
- 2003
46. [Radiofrequency ablation of pulmonary malignancies]
- Author
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Masami, Toyoshima, Toshiyuki, Matsuoka, Tomohisa, Ohkuma, Akira, Yamamoto, Yoshimasa, Ohyama, Saori, Tanaka, Kenji, Nakamura, Ryusaku, Yamada, Yuichi, Inoue, Kiyotoshi, Inoue, Tatsuya, Nishida, and Noriaki, Usuki
- Subjects
Aged, 80 and over ,Male ,Lung Neoplasms ,Treatment Outcome ,Catheter Ablation ,Humans ,Middle Aged ,Aged - Abstract
Radiofrequency ablation (RFA) with a maximum output ofor = 70 W was used under CT guidance to treat 14 tumors (median diameter 1.5 cm, range 0.8 to 2.4 cm) in 6 patients. Primary lung cancer was treated in 2 patients, and metastatic lung tumors were treated in 4 patients. Good response was confirmed in 6 tumors on CT images, in one tumor on PET images, and in 2 tumors by histologic examination. In the other 5 tumors, curative effect was not determined because consolidation shadows surrounded the tumors. Complications were mild (pneumothoraces, 5; sputum cruentum, 4; subcutaneous emphysema, 3) except for one case of pleurisy. RFA of pulmonary malignancies appears to be a safe, effective treatment if a low output of less than 70 W is applied.
- Published
- 2003
47. Inhibition of neointimal hyperplasia by heat stress in an experimental model
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Ryusaku Yamada, Norihumi Nishida, Kenji Nakamura, Masao Hamuro, Toshiyuki Matsuoka, and Kaminou T
- Subjects
Intimal hyperplasia ,Hot Temperature ,Endothelium ,Endothelial Growth Factors ,Muscle, Smooth, Vascular ,Andrology ,Biological Factors ,Restenosis ,In vivo ,Heat shock protein ,medicine ,Animals ,Radiology, Nuclear Medicine and imaging ,Heat-Shock Proteins ,Neointimal hyperplasia ,Hyperplasia ,business.industry ,Angioplasty ,Anatomy ,medicine.disease ,Coculture Techniques ,Endothelial stem cell ,medicine.anatomical_structure ,Models, Animal ,Endothelium, Vascular ,Rabbits ,Cardiology and Cardiovascular Medicine ,business ,Cell Division - Abstract
PURPOSE To evaluate the potential effect of heat stress in inhibiting neointimal hyperplasia after angioplasty in an experimental model. MATERIALS AND METHODS In vitro, proliferation and migration of heat-stress–induced and noninduced cells were compared with use of an endothelial cell/smooth muscle cell coculture model (five culture dishes in each experiment). Mild heat stress was induced via exposure of cultures to a temperature of 42°C for 2 hours. In vivo, the neointimal thickness of ear arteries of Japanese white rabbits 7 days after denudation of endothelium was histologically evaluated in the control and heat-stress–induced groups (three rabbits in each group). RESULTS Proliferation of heat-stress–induced smooth muscle cells declined significantly compared with that of noninduced cells in single-culture and coculture models. The migration rates of neither endothelial cells nor smooth muscle cells were significantly affected by heat stress. In vivo, the mean neointimal thickness was 13.8 μm ± 8.0 in the control group and 3.9 μm ± 2.1 in the induced group ( P CONCLUSION Induction of mild heat stress has great potential to reduce neointimal hyperplasia after angioplasty because it inhibits smooth muscle cell proliferation without inhibiting endothelial migration in vitro and suppresses neointimal growth in vivo.
- Published
- 2002
48. Power Doppler ultrasonographic diagnosis of small hepatocellular carcinomas
- Author
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Taichi Shuto, Shoji Kubo, Kazuhiro Hirohashi, Hiromu Tanaka, Yoshihiko Morimoto, Ryusaku Yamada, Takatsugu Yamamoto, and Hiroaki Kinoshita
- Subjects
Male ,medicine.medical_specialty ,Carcinoma, Hepatocellular ,Hemodynamics ,Sensitivity and Specificity ,Sampling Studies ,Power doppler ,Preoperative Care ,medicine ,Humans ,Prospective Studies ,Aged ,Neoplasm Staging ,business.industry ,fungi ,Biopsy, Needle ,Liver Neoplasms ,Gastroenterology ,food and beverages ,Ultrasonography, Doppler ,Middle Aged ,medicine.disease ,Prognosis ,Radiographic Image Enhancement ,Hepatocellular carcinoma ,cardiovascular system ,Surgery ,Female ,Radiology ,Ultrasonography ,business ,Tomography, X-Ray Computed ,circulatory and respiratory physiology - Abstract
Background/Aims: Power Doppler ultrasonography can evaluate the hemodynamics of intrahepatic tumors. The ability of power Doppler ultrasonography to detect small hepatocellular carcinomas and estimate the differentiation of the tumor by the patterns of intranodular waves was assessed. Methods: We used conventional B-mode ultrasonography, power Doppler ultrasonography, and dynamic computed tomography to examine 71 hepatocellular carcinomas (≤3 cm) before liver resection. Results: The sensitivity of conventional ultrasonography, power Doppler ultrasonography, and computed tomography increased as tumor diameter increased, with little difference between modalities. Nodules up to 5 mm in diameter as well as some nodules in the lateral segment or the subphrenic area of the liver were not detected by power Doppler ultrasonography, although two nodules not detected by computed tomography were apparent from power Doppler ultrasonography. With the latter modality, the proportion of nodules with afferent pulsatile waves was higher in moderately or poorly differentiated hepatocellular carcinomas than in well-differentiated hepatocellular carcinomas. Afferent continuous waves were detectable only in well-differentiated hepatocellular carcinomas. Conclusion: Although the sensitivity of power Doppler ultrasonography remains unsatisfactory for minute lesions (≤5 mm) and for laterally or subphrenically situated lesions, this method can usually distinguish moderately or poorly differentiated from well-differentiated hepatocellular carcinomas, which is useful in planning treatment and predicting outcome.
- Published
- 2002
49. Brachytherapy for the prevention of neointimal hyperplasia in the canine inferior vena cava after stent placement
- Author
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Masayuki, Isota, Toshio, Kaminou, Yukimasa, Sakai, Kenji, Nakamura, and Ryusaku, Yamada
- Subjects
Dogs ,Hyperplasia ,Brachytherapy ,Animals ,Radiotherapy Dosage ,Stents ,Vena Cava, Inferior ,Muscle, Smooth, Vascular - Abstract
The aim of this study was to evaluate the efficacy of brachytherapy for preventing neointimal hyperplasia in the inferior vena cava (IVC) after stent placement. Sixteen beagles underwent Z-stent placement in the IVC and the aorta. For 8 of 16 beagles, irradiation (15 Gy) was delivered endoluminally to the stented segments of each vessel immediately after stent placement using the 192Ir. All animals were sacrificed after 6 weeks for morphometric and histopathologic examination. Morphometrically, neointimal thickness in the IVC of the radiation group was significantly decreased compared with the control group as well as that in the aorta (p0.05). Histopathologic findings showed the neointima in the IVC of the control group contained markedly organization of thrombus and neovascularization though that in the IVC of the radiation group consisted mainly of smooth muscle cells without organization of thrombus and neovascularization. From these data intravenous irradiation may prevent clinical restenosis after stent placement.
- Published
- 2002
50. Alterations to hepatic microcirculation in thioacetamide-induced cirrhotic livers of rats
- Author
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Manabu, Nakata, Kenji, Nakamura, Yoichi, Koda, Toshio, Kaminou, Masayuki, Ogami, and Ryusaku, Yamada
- Subjects
Male ,Microcirculation ,Hemodynamics ,Animals ,Rats, Wistar ,Thioacetamide ,Liver Cirrhosis, Experimental ,Liver Circulation ,Rats - Abstract
In liver cirrhosis, increased resistance of intrahepatic microvasculature contribute to the development of portal hypertension. This study aimed to reveal the alterations to hemodynamics in microvasculature of thioacetamide-induced fibrotic and cirrhotic rat livers, using in vivo microscopy. In fibrotic livers, although intrahepatic blood flow remained unaltered, area percentage of sinusoids was significantly decreased. In cirrhotic livers, intrahepatic blood flow was significantly increased concurrently with decrease in area percentage of sinusoids. The flow velocity and volume flow were significantly increased in terminal portal venules (TPVs) without changes in vascular diameters, whereas all these parameters were not altered in terminal hepatic venules (THVs). Intrahepatic shunts which emerged from TPVs and ran toward THVs, and anastomoses between neighboring THVs were formed in cirrhotic livers. These data indicate that the first occurring alteration of microcirculation in liver cirrhosis is decrease in sinusoidal beds.
- Published
- 2002
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