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Biomedical subjects

H Uchida

Publications and source records attributed to H Uchida.

At least 829 records · Page 46Linked to original sources
PubMedDate not supplied

Optimal dose of hepatobiliary contrast agent for MR cholangiography: experimental study in rats.

The purpose of this study is to clarify the optimal dose of gadolinium-ethoxybenzyl-diethylenetriaminepentaacetic acid (Gd-EOB-DTPA) for cholangiography in conventional T1-weighted imaging. We divided 30 rats into three dose groups (3, 10, and 30 micromol/kg). For the in vitro study, we collected bile and measured the concentration of gadolinium in bile after Gd-EOB-DTPA injection. T1-weighted images of the collected bile were obtained for measurement of signal intensity. For the in vivo study, we obtained T1-weighted images before and after injection and evaluated bile duct/liver contrast by the signal intensity ratio and visual assessment of the images. The gadolinium concentration had an early peak; however, the signal intensity of the bile had a later peak because of the high gadolinium concentration during the early phase, which induced a T2-shortening effect. Optimal bile duct/liver contrast was obtained in the 10-micromol/kg groups at all time points. We conclude that the optimal dose of Gd-EOB-DTPA for MR cholangiography in rats is 10 micromol/kg, one-third of the dose used in liver imaging.

Animals↗
PubMedDate not supplied

Determination of the optimum dose level of lipiodol in transcatheter arterial embolization of primary hepatocellular carcinoma based on retrospective multivariate analysis.

PURPOSE: Multivariate analysis was used to study the effectiveness and optimum dose level of Lipiodol (LP) in transcatheter arterial embolization (TAE) of hepatocellular carcinoma (HCC). METHODS: A total of 219 cases of nodular type HCC, with a tumor diameter less than 7 cm, were studied. TAE was performed using both Gelfoam sponge (GS) and LP in 158 cases; in the remaining 61 cases only GS was used. RESULTS: Statistical stepwise variable selection revealed that only LP had a negative T-value, suggesting that LP is a useful factor for prognosis. The most favorable effect on patient prognosis was obtained with an LP dose level (expressed in mm) of 1-1.5 times the absolute value of the tumor diameter (expressed in cm). CONCLUSION: A significant difference (p < 0.01, log-rank test) in survival was found between the GS with LP group and the GS only group, using Cox's proportional hazard model.

Carcinoma, Hepatocellular↗
PubMedDate not supplied

Transcatheter hepatic segmental arterial embolization using lipiodol mixed with an anticancer drug and Gelfoam particles for hepatocellular carcinoma.

Transcatheter hepatic segmental arterial chemoembolization using Lipiodol mixed with an anticancer drug followed by the injection of Gelfoam particles, introduced into the tumor-bearing hepatic segment as the target area (segmental Lipiodol-TAE), was carried out in 54 patients with hepatocellular carcinoma (HCC), 7 of whom were later resected. In 5 of the resected 7 cases, complete necrosis was histologically verified. No death due to HCC was encountered in 47 nonoperated cases, and better therapeutic results were obtained with segmental Lipiodol-TAE. It was concluded that this technique does not adversely affect normal tissues, and it does reinforce the effect of TAE.

Carcinoma, Hepatocellular↗
PubMedDate not supplied

Segmental embolotherapy for hepatic cancer: keys to success.

Transcatheter chemoembolization using Lipiodol (Lp) mixed with chemotherapeutic agents followed by Gelfoam particle injection only to the tumor-bearing hepatic segment (segmental Lp transcatheter hepatic artery embolization) (TAE) was applied to more than 100 patients with hepatocellular carcinoma and metastatic liver cancer. For segmental Lp-TAE, knowledge of the variations of intrahepatic arterial anatomy is important. Furthermore, the catheters and guidewires, volume of Lp, kinds and dose of chemotherapy, preparation of the mixture of Lp and chemotherapy (Lp-emulsion), method of injection of Lp-emulsion and Gelfoam particles, as well as the follow-up computed tomography examination are key items to the success of the procedure and are reviewed.

Antineoplastic Agents↗
PubMedDate not supplied

Application of a self-expanding metallic stent to a strictured esophagojejunostomy.

We placed a Gianturco self-expanding metallic stent across the recurrent stricture of an esophagojejunostomy in a patient with gastric cancer. Though excellent passage of food resulted, intractable reflux occurred. Two months later the patient succumbed to recurrent tumor. At autopsy, the stent was patent and was partially covered by esophageal mucosa. There were narrow but deep ulcers around the stent hooks. The Gianturco metallic stent may provide an additional option for treating recurrent enteric strictures after other methods fail. Further refinements of the technique appear necessary.

Aged↗
PubMedDate not supplied

Crossover approach with a J-shaped sheath for angioplasty of iliofemoral artery stenoses and occlusions.

Thirty patients with atherosclerotic stenoses or occlusions of iliofemoral arteries were treated from the contralateral approach using a newly designed J-shaped sheath. Seven patients with stenoses and one with an occlusion were successfully dilated with balloon angioplasty. Twenty-two patients with occlusions were treated with urokinase infusion, 16 of whom received coaxial infusion with the J-shaped sheath and catheter. Complete thrombolysis was achieved in 18 patients. The treatment success rate was 100% in the stenotic group and 83% in the occlusion group. Initially, J-shaped sheaths were useful for treatment of iliofemoral artery lesions from the contralateral femoral artery.

Angioplasty, Balloon↗
PubMedDate not supplied

Combined transjugular intrahepatic portosystemic shunt and segmental Lipiodol hepatic artery embolization for the treatment of esophagogastric varices and hepatocellular carcinoma in patients with cirrhosis: preliminary report.

PURPOSE: To evaluate the feasibility of combining placement of a transjugular intrahepatic portosystemic shunt (TIPS) and transcatheter hepatic segmental artery chemoembolization with Lipiodol (Seg-Lp-TAE) in patients with cirrhosis, esophagogastric varices, and hepatocellular carcinoma (HCC). METHODS: Five patients with bleeding or large, high-flow esophagogastric varices and HCC were treated by TIPS and Seg-Lp-TAE. RESULTS: The mean portosystemic pressure gradient decreased from 20.8 cm H2O to 7.8 cm H2O after TIPS. The direct portogram and endoscopic examination revealed reduction of varices. At 6 months, one shunt had functionally occluded and could not be reopened; the other TIPS remained functional. Follow-up CT and the changes of alpha fetoprotein indicated effective therapy of Seg-Lp-TAE for HCC. Four patients are in stabile clinical condition at 9, 6, 1, and 1 months after the combined therapy; one died after 14 months due to decompensated liver cirrhosis. CONCLUSION: The combined therapy of TIPS and Seg-Lp-TAE will become a new interventional approach for patients with HCC and esophagogastric varices.

Aged↗
PubMedDate not supplied

Long-term palliative treatment of hepatocellular carcinoma extending into the portal vein and bile duct by chemoembolization and metallic stenting.

We present a patient with hepatocellular carcinoma accompanied by portal vein and bile duct tumor thrombi. The patient was treated with a spiral Z-stent covered by a polyethylene sheet placed in the bile duct, a Wallstent placed in the portal vein, chemoembolization, and external radiation therapy. The patient is alive with patency of both endoprostheses 18 months later.

Antibiotics, Antineoplastic↗
PubMedDate not supplied

Effect of antithrombotic agents on the patency of PTFE-covered stents in the inferior vena cava: an experimental study.

PURPOSE: To evaluate the efficacy of antithrombotic agents in the prevention of stenosis of polytetrafluoroethylene (PTFE)-covered stents in the venous system. METHODS: Spiral Z stents covered with PTFE (PTFE-covered stents) were placed in the inferior vena cava (IVC) of 34 dogs. Nineteen dogs, used as a control group, were sacrificed at 2, 4, and 12 weeks. Fifteen dogs, previously given antithrombotic agents [cilostazol (n = 5), warfarin potassium (n = 5), cilostazol plus warfarin potassium (n = 5)] were sacrificed at 4 weeks, and then examined angiographically and histopathologically. The effect of the antithrombotic agents was compared between groups. RESULTS: The patency rate of the antithrombotic agent group was 93% (14/15), which was higher than the control group rate of 63% (12/19). The mean stenosis rate of the patent stent at both ends and at the midportion was lower at 4 weeks in the antithrombotic agent group than in the control group. In particular, the mean stenosis rate in the cilostazol plus warfarin potassium group was significantly lower than the control group (Tukey's test, p < 0.05). The mean neointimal thickness of the patent stent at both ends and at the midportion was thinner at 4 weeks in the antithrombotic agent group than in the control group. In particular, the thickness of the neointima in the cilostazol plus warfarin potassium group was significantly decreased when compared with the control group (Tukey's test p < 0.05). At 4 weeks, endothelialization in the antithrombotic agent group tended to be almost identical to that in the control group. CONCLUSION: The present study suggests that administration of an antithrombotic agent is an effective way of preventing the stenosis induced by a neointimal thickening of PTFE-covered stents in the venous system.

Animals↗
PubMedDate not supplied

Anomaly of the inferior vena cava observed by CT.

Computed tomography (CT) is a good modality for diagnosing diseases of the retroperitoneal space and capable of showing the abnormality of inferior vena cava (IVC) without using invasive technique. To determine the incidence of the anomaly of IVC, the computed tomograms were investigated retrospectively. The incidence were 0.69% in left side IVC, 1.03% in double IVC and 0.08% in azygos continuation.

Azygos Vein↗
PubMedDate not supplied

Case study of a five-stage sensory reeducation program.

The purpose of this paper is to describe a sensory reeducation program classified into five stages: (1) feature detection and recognition of objects; (2) correction of the pattern of prehension in the hand; (3) control of precise force for grasping objects; (4) maintenance of grip force during movement of the proximal joints; and (5) manipulation of objects. The program is specific to hand function in activities of daily living and is based on recent neurophysiological findings. It is illustrated by a detailed case study. The authors report that, through sensory reeducation a patient who had an insensitive hand gained the ability to recognize objects. She learned to utilize a sense of muscle resistance and a sense of vibration in the shoulder. Her body image improved along with the usefulness of her hand in activities of daily living.

Clinical Protocols↗
PubMedDate not supplied

Segmental transcatheter hepatic artery chemoembolization with iodized oil for hepatocellular carcinoma: antitumor effect and influence on normal tissue.

PURPOSE: Segmental transcatheter arterial embolization (TAE) with use of iodized oil mixed with an anticancer drug, followed by injection of gelatin sponge particles, was undertaken to evaluate its antitumor effect and its influence on normal tissue in patients with hepatocellular carcinoma (HCC). PATIENTS AND METHODS: Histologic findings in 12 patients who underwent hepatectomy after segmental TAE were compared with findings on plain radiographs and computed tomographic (CT) scans. Visualization of the portal veins contiguous to the tumor on radiographs and the pattern of iodized oil accumulation in the tumor and vicinity on CT scans after TAE were assessed. RESULTS: Complete necrosis of the tumor was achieved in 10 cases (83%), while complete necrosis of daughter nodules and capsular invasion was observed histologically in eight of these 10 patients (80%). The degree of tumor necrosis correlated with the pattern of iodized oil accumulation in and near the tumor. Partial necrosis of normal tissue near the tumor correlated with accumulation of iodized oil. CONCLUSION: Segmental TAE may be an excellent therapeutic method for treatment of HCC that is localized in one or a few segmental or subsegmental regions.

Aged↗
PubMedDate not supplied

Current status of angiography and interventional radiology in Japan: survey results.

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 angioplasty (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.

Adult↗