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Y Shioyama

Publications and source records attributed to Y Shioyama.

At least 37 records · Page 2Linked to original sources
PubMed1994

[Intimal hyperplasia growth after stenting of modified gianturco Z stent in an experimental study].

Three types of modified Gianturco Z stents, which included some solder at the bend portion in group 1, a little solder in group 2 and no solder in group 3, were placed in the jugular vein in order to evaluate the degree of intimal hyperplasia growth in five dogs. Four weeks later, venography and histological examination after venectomy were performed. Stenosis was 32.7 +/- 6.9% at the bend portion in group 1, 27.0 +/- 6.0% in group 2 and 14.0 +/- 6.5% in group 3. The results indicate that stents without solder are preferable for the venous system.

Animals↗
PubMed1994

[Self-expandable metallic stent therapy for inferior vena cava obstruction secondary to malignancy: clinical observations].

To evaluate the self-expandable metallic stent therapy for inferior vena caval obstruction (IVCO) secondary to malignant liver tumors, changes in caval pressure, the symptoms and hemobiochemical values were observed. Among 16 IVCO cases with higher caval pressure than 20 cmH2O at the peripheral caval lumen to the stenosis, nine cases consisting of five extracaval compression cases and four intravenous tumor thrombi cases subjected the stent therapy. Other three subjected radiotherapy and the other four cases inactive supportive care. Immediately after the Z-stent implantation, the averaged caval pressure distal to the stenosis decreased from 27.7 +/- 3.5 cmH2O to 14.7 +/- 2.6 cmH2O. One case developed 8 cmH2O increase of right atrial pressure but no lung edema. The urine excretion volume increased after stent. The decrease in caval pressure correlated with the urine volume of the day after the stenting (gamma = 0.83), symptomatic improvements of leg edema (gamma = 0.68), ascites (gamma v 0.51) and scrotal edema (gamma = 0.70). Five cases showed gradual increase in platelet number. All elevated LDH and elevated fibrinogen value decreased. These changes would suggest physiologic benefits of the IVC stent therapy. Compression cases showed better improvements and courses than the thrombi cases. Two thrombi cases endured severe conditions suspected of triggered by the procedure. Conclusively, the stent therapy to the IVC obstruction was thought to effect hemodynamically and hematobiochemically.

Aged↗
PubMed1994

Acute toxicity of lipiodol infusion into the hepatic arteries of dogs.

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.

Acute Disease↗
PubMed1993

Lumbar artery pseudoaneurysm: an unusual cause of a retroperitoneal hematoma: report of a case.

Pseudoaneurysm of the lumbar artery is a rare complication of penetrating trauma. We present herein a case thought to have been caused by a blow to the left flank without any evidence of a stab wound. In this patient, the diagnosis of a first lumbar artery pseudoaneurysm with a retroperitoneal hematoma was confirmed by computed tomography (CT) findings, after which transcatheter embolization was successfully performed.

Aneurysm↗
PubMed1991

[Differential diagnosis between recurrence of brain tumor and radiation necrosis by 201Tl SPECT].

In order to differentiate recurrence of brain tumor from radiation necrosis, we performed 201Tl brain SPECT in 16 post-operative patients. Five of them had residual anaplastic astrocytoma. Final diagnosis of the other 11 patients was recurrent astrocytoma (n = 6), cerebral radiation necrosis (n = 5), based on re-operation (n = 9) and more than one year follow-up finding (n = 2). Early and delayed images were obtained at 10-15 min. and 4 hrs. after i.v. injection of 111 MBq of 201Tl chloride. Counts ratio of a lesion to the normal brain (L/N) was calculated by creating rectangular ROI over each area. All of the patients with recurrent or residual tumor showed L/N ratios of more than 2.5 on the early images (mean 4.70 +/- 2.65). On the other hand, L/N ratios on the early images were less than 2.5 in patients with radiation necrosis (mean 2.05 +/- 0.25, p less than 0.001). In conclusion, a quantitative assessment using 201Tl brain SPECT may be useful in differentiating recurrence of brain tumor from radiation necrosis.

Adult↗
PubMed1991

[67Ga citrate imaging in AIDS-related Pneumocystis carinii pneumonia in Japan].

Six AIDS patients with Pneumocystis carinii pneumonia (PCP) underwent 67Ga scan as part of their evaluation. Only one patient of them showed the characteristic 67Ga distribution pattern for PCP, that is, diffuse, increased, bilateral lung activity greater than liver activity. Two patients who were receiving therapy for PCP and one patient with recurrent PCP showed focal or uneven 67Ga lung uptake. In the four patients, the scan showed more extensive lesion than the chest radiograph. The other two patients who died 2 months later of cellular immunodeficiency showed no or very slight lung uptake of 67Ga. In summary, 67Ga scanning is useful diagnostic procedure in evaluation of PCP in patients with AIDS.

Acquired Immunodeficiency Syndrome↗
PubMed1990

[The movement of antineoplastic solutions in transcatheter hepatic arterial embolization].

Transcatheter hepatic arterial embolization (TAE) with gelatin sponge particles soaked in anticancer agents has been widely employed in the treatment of Hepatocellular carcinoma (HCC). The mechanism of TAE has been explained by blocking of blood flow to the tumor, however the role of anticancer agents used with embolic materials has remained unclear. The purpose of this study is to prove the role of anticancer agents used in TAE. 1) In eighteen cases of HCC and 4 cases of metastatic liver cancer, TAE was performed with gelatin sponge, anticancer agents and contrast media. The livers were examined by CT 4, 24 and 48 hours after TAE. A selective retention of contrast media containing anticancer agent in the tumor area was observed in 14 of 14 cases examined 4 hr. in 15 of 17 cases examined 24 hr and in 6 of 6 cases examined 48 hr after TAE. In the cases of metastatic liver cancer, retention of contrast media, was also observed in 4 of 4 cases examined at 24 hr and 3 of 3 cases examined 48 hr after TAE. 2) TAE was done in 12 cases of HCC by using gelatin sponge soaked in anticancer agent mixed with 99M-Tc-pertechnetate. Livers were observed by a scintillation camera 4 hr and 24 hr after TAE. A selective retention of 99M-Tc-pertechnetate in the tumor was observed in 12 of 12 cases examined 4 hr and in 3 of 3 cases examined 24 hr after TAE. 3) In one cases of HCC, hepatectomy was performed 2 days after TAE.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1990

[Effects of experimental hepatic artery embolization with lipiodol and gelatin sponge on liver tissue].

The effect of hepatic artery embolization with Lipiodol (Lp) and Gelatin sponge particles (GSP) on liver tissue was evaluated in 17 dogs embolized with GSP, 12 dogs with Lp and 19 dogs with Lp + GSP. Survival rate and extent of liver damage were used as evaluation criteria. None of the dogs with GSP died during the 4 week period, two exhibited small liver infarctions. Of the dogs with 0.2 to 5 ml/kg Lp, two dogs with 4 ml/kg or 5 ml/kg Lp died of cardiac failure. Gross liver examination did not show any liver infarction. Eight of the 19 dogs with Lp + GSP died of liver failure. Gross examination of the surviving dogs demonstrated infarction in 9 of the 11 livers with 100% incidence in those with 0.2 ml/kg or 0.5 ml/kg Lp. Liver infarction increased in size with the increase of Lp volume. In combination with Lp + GSP, the Lp volume should be less than 0.1 ml/kg.

Animals↗
PubMed1990

[Usefulness of ventilation and perfusion scans in patients with collagen-vascular diseases].

We studied 32 patients with collagen-vascular diseases with Xe-133 ventilation scans (V) and Tc-99m MAA perfusion scans (Q). Five patients underwent sequential studies at intervals of more than 3 months. Mean transit time (MTT) was calculated from the Xe-133 wash-out curve. V, Q images and MTT were compared with chest X-ray films and the values of %DLco. Of 32 patients, 17 had no abnormal finding on the chest X-ray films. Of the 17 patients, however, V and/or Q abnormalities were found in 10 (59%), 14 patients (82%), respectively. Every patient with abnormal findings on the chest X-ray film showed both V and Q abnormalities. Overall, Q abnormality was more frequent and severer than V one. Of the 5 patients with the sequential studies, 3 showed prolongation of MTT in concordance with deterioration of pulmonary fibrosis. V and Q abnormalities were not necessarily relevant to %DLco. In conclusion, ventilation and perfusion studies are useful in assessing the regional pulmonary function in patients with collagen-vascular diseases.

Adult↗
PubMed1990

[Arterial stasis chemotherapy].

"Arterial stasis chemotherapy" is a concept which summarizes administration methods of anticancer agents under the temporary blockade of the blood flow by any means. The drugs so infused is hardly diluted by blood flow, reaching the tumor tissue in high concentration and staying there much longer than that of administered by simple arterial infusion. "Arterial stasis chemotherapy" contains TAE (transcatheter arterial embolization) with gelatin sponge. TAE with ethiodol, TAE with microencapsulated anticancer drug, BOAI (balloon occluded arterial infusion), arterial administration of SMANCS/Lipiodol, intra-arterial administration of DSM (degradable starch microsphere) and so on. The authors confirmed that anticancer agents, which were soaked in gelatin sponge particles, densely stayed in the tumor for twenty hours after TAE using CT and iodinated contrast media. And we also confirmed a high level of the drug was present selectively in the tumor tissue for a longer time when it was given by BOAI than SAI using scintillation camera and Xe. After these basic studies, we applied TAE and BOAI on the patients with malignant tumors and got much better therapeutic effects than previous reports. We believe therapies based on the concept of "Arterial stasis chemotherapy" will prevail from now on.

Aged↗