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Biomedical subjects

Satoshi Sawada

Publications and source records attributed to Satoshi Sawada.

At least 19 recordsLinked to original sources
PubMed2006

Leiomyoma of the trachea: CT and MRI findings.

A 47-year-old woman with a tracheal leiomyoma is described. Leiomyoma is a rare benign tumor of the trachea. Only 43 cases have been reported in the English- and Japanese-language literature. To our knowledge, this is the second time magnetic resonance imaging (MRI) findings have been reported. MRI can help discriminate between masses with a stalk and masses with a broad base, which in turn can help determine whether surgical resection of the tracheal leiomyoma is appropriate.

Female↗
PubMed2006

Percutaneous vertebroplasty: relationship between vertebral body bone marrow edema pattern on MR images and initial clinical response.

PURPOSE: To prospectively investigate the relationship between initial clinical response and bone marrow edema pattern on preprocedural magnetic resonance (MR) images in vertebral bodies selected for percutaneous vertebroplasty (PVP). MATERIALS AND METHODS: Institutional review board approval and written informed consent were obtained. PVP was performed for osteoporotic compression fractures in 80 consecutive patients (mean age, 72.4 years; range, 44-85 years; 67 women and 14 men; 157 vertebrae). Patients were divided into three groups according to the proportion of the vertebra in which the bone marrow edema pattern was observed on sagittal MR images: group 1, 50% or more of the vertebra; group 2, less than 50%; group 3, no edema pattern observed. By using Wilcoxon rank sum test, Fisher exact test, and Wilcoxon signed rank test, groups were examined for differences in treatment efficacy, which was defined as the difference between preprocedural and postprocedural pain as assessed by means of visual analog scale (VAS) score at 1-3 days after PVP. RESULTS: Forty-four patients were assigned to group 1, 14 to group 2, and 22 to group 3. No significant difference was seen between the groups with respect to age, sex, number of treated vertebrae, or preprocedural VAS score. In group 1, VAS score decreased from 7.5 before the procedure to 2.9 after (improvement of 4.6). In group 2, the score decreased from 6.8 to 3.1 (improvement of 3.7). In group 3, the score decreased from 7.0 to 4.3 (improvement of 2.7). Improvement was significantly greater in group 1 than in group 3 (P < .005). CONCLUSION: PVP resulted in significantly greater clinical improvement in patients with an extensive bone marrow edema pattern than in those without this pattern. (c) RSNA, 2006.

Adult↗
PubMed2006

[Basic experimental study of intraosseous venography using carbon dioxide contrast agent in percutaneous vertebroplasty].

PURPOSE: In percutaneous vertebroplasty (PVP), intraosseous venography is performed using water-soluble ionic iodinated contrast media (iodine contrast media) before injecting bone cement. However, because of contrast medium remaining in the fractured cleft, we experienced the persistence of intravertebral opacification that obscured visualization of the cement under X-ray fluoroscopy. To solve this problem, we examined carbon dioxide (CO(2)) as a contrast medium. METHODS: We measured the contrast of iodine contrast media and CO(2) and performed a subjective assessment of imaging by enforcing intraosseous venography by changing the tube voltage and image intensifier (I.I.) entrance dose in a bone sample of a cadaver using iodine contrast media and CO(2). In vivo study, we performed a subjective assessment of images obtained by intraosseous venography using CO(2) under two kinds of X-ray views. RESULTS: We determined that the contrast of CO(2) is 1/6-1/7.5 that of iodine contrast media, and that CO(2) fluctuates less in its contrast value with changes in tube voltage. In our assessment of the image of the bone sample, CO(2) performed worse that iodine contrast media. However, if the I.I. entrance dose is kept above 2.5 microGy/F, CO(2) is considered to be of clinical use. In the clinical image assessment, the best conditions were an image collection rate of 7.5 F/S and matrix of 1024 x 1024. CONCLUSIONS: CO(2) did not cause any obstacles when we injected bone cement, and its I.I. entrance dose, image collection rate, and matrix size indicate that it can be used for intraosseous venography.

Bone Cements↗
PubMed2006

A case of spontaneous regression of hepatocellular carcinoma with multiple lung metastases.

Spontaneous regression of hepatocellular carcinoma (HCC) is a rare phenomenon. We present herein the case of a patient with hepatocellular carcinoma with multiple lung metastases in whom malignancy spontaneously regressed after taking Pheliinus linteus Mycelium. A 79-year-old man consulted our hospital complaining of epigastric discomfort. Abdominal MRI and CT revealed a 3 cm diameter tumor in the liver, and chest CT showed numerous nodular lesions. The levels of alpha-fetoprotein (AFP) and protein induced by vitamin K deficiency or antagonist-II (PIVKA-II) were very high. We diagnosed HCC with multiple lung metastases, and no therapy was performed. Independently he took exact from Phellinus linteus Mycelium for one month, and 6 months later the tumors appeared to be in complete regression. The mechanism underlying this intriguing phenomenon remains unknown.

Aged↗
PubMed2006

Non-necrotic invasive squamous cell carcinoma associated with an inverted papilloma: MRI features.

We present the MRI findings of a carcinoma associated with an inverted papilloma located in the nasal cavity. This tumor can be divided into 2 types, those with and those without gross central necrosis. In our case, the tumor did not have any gross central necrosis, and MRI showed convoluted cerebriform patterns. We found that MRI is unable to distinguish malignant and benign regions in a central mass with no gross necrosis, since this lesion does not alter the basic morphological pattern of inverted papilloma.

Carcinoma, Squamous Cell↗
PubMed2006

Acupuncture-induced cerebral blood flow responses in dystonia.

OBJECTIVE: The effect of acupuncture (ACP) on regional cerebral blood flow (rCBF) is unclear. Single-photon emission computed tomography studies on three patients with dystonia were performed before and after ACP treatment to test the contention that ACP affects rCBF. METHODS: Pre-ACP and post-ACP CBF study were performed on the same day; 99mTc ethyl cysteinate dimer was injected for each study. rCBF images were analyzed using a three-dimensional stereotaxic ROI template (3DSRT) to objectively measure rCBF. We evaluated rCBF bilaterally in five segments related to the pathophysiology of dystonia (1, superior frontal; 2, middle and inferior frontal; 3, primary sensorimotor; 4, lenticular nucleus; and 5, thalamus). More than 10% left-right asymmetry in rCBF over three continuous slices was defined as significant laterality. Post-ACP rCBF and laterality were evaluated with the pre-ACP rCBF study acting as a control in each subject. RESULTS: The clinical effect of ACP was remarkable in all patients and rCBF increased in most segments. Pre-ACP rCBF exhibited significant laterality in eight segments of the three patients. Laterality reversed in seven of these segments and resolved in the remaining segment after ACP. Pre-ACP rCBF laterality was not preserved in any segment after ACP. The remaining five segments exhibited laterality only after ACP. In total, after ACP, 13 of 15 segments demonstrated a change in CBF that was greater unilaterally. CONCLUSIONS: ACP results in an increase in CBF that is greater unilaterally. We think that unilateral change in CBF may be correlated with the action of ACP on the central nervous system in patients with dystonia.

Acupuncture Therapy↗
PubMed2006

Spontaneous rupture of a necrotic hepatic angiosarcoma: findings on dual-phase computed tomography and angiography.

We present dual-phase computed tomographic (CT) and angiographic findings of a ruptured hepatic angiosarcoma. These tumors can be divided into two types: those with and those without gross central necrosis with hemorrhage. In our case, the tumor had gross central necrosis, and CT and angiographic findings showed a small number of areas with a centripetal enhancement pattern and the rest of the tumor with avascular areas. We found that dual-phase CT and angiographic findings are able to distinguish angiosarcoma, which mimics a hemangioma, as these lesions show avascular areas that reflect a mass with gross central necrosis.

Angiography↗
PubMed2005

Radiation exposure to operators during vertebroplasty.

PURPOSE: To measure the radiation received by physicians during percutaneous vertebroplasty with use of two types of injection devices with the interventional equipment guided by computed tomography (CT) and an angiographic/CT system. MATERIALS AND METHODS: Twenty consecutive patients who underwent percutaneous vertebroplasty were included in this study. The patients were divided into two groups, the 1-mL syringe group and the bone cement injector group. Percutaneous vertebroplasties were performed with the IVR-CT system, which combines angiographic and CT equipment with a single fluoroscopy table. Radiation dose to operators was measured as equivalent dose penetrating at a 10-mm tissue depth with use of electronic personal dosimeters attached outside and inside lead aprons. Effective radiation dose (HE) was estimated based on the radiation dose outside the lead apron (Ha) and the radiation dose inside the lead apron (Hb). Differences between the groups in doses and fluoroscopic duration were analyzed. RESULTS: In the 1-mL syringe group and bone cement injector group, mean Ha measurements were 320.8 microSv and 116.2 microSv, respectively. Mean Hb measurements were 14.5 microSv versus 7.8 microSv and mean HE measurements were 48.2 microSv versus 19.7 microSv. Significant differences were found in Ha, Hb, and HE. However, duration of fluoroscopy did not differ significantly between groups. CONCLUSIONS: Radiation dose was relatively high for operators performing percutaneous vertebroplasty. The bone cement injector was useful in reducing the level of radiation exposure to operators during vertebroplasty.

Fluoroscopy↗
PubMed2005

Radiofrequency ablation combined with CO2 injection for treatment of retroperitoneal tumor: protecting surrounding organs against thermal injury.

OBJECTIVE: The objective of this study was to separate target tumors from adjacent structures by injecting carbon dioxide (CO2) around the tumor to avoid thermal injury and the heat-sink effect from the blood vessel during percutaneous radiofrequency ablation. CONCLUSION: We successfully achieved complete ablation of a retroperitoneal tumor without thermal injury. Imaging-guided percutaneous CO2 injection is useful for preventing thermal injury while achieving complete ablation of the tumor during radiofrequency ablation.

Adrenal Gland Neoplasms↗
PubMed2005

Intraosseous venography with carbon dioxide contrast agent in percutaneous vertebroplasty.

OBJECTIVE: Our objectives were to ascertain whether CO2 can be used as a contrast agent in venography during percutaneous vertebroplasty and to evaluate whether it might be capable of replacing nonionic iodinated contrast agents. CONCLUSION: Intraosseous venography with CO2 contrast agent was slightly inferior to iodine venography in terms of its ability to visualize the vertebral bodies and perivertebral veins, but it remains a useful technique because no interference with optimal visualization of bone cement occurs during the cement injection when CO2 remains within the fracture cleft.

Aged↗
PubMed2005

Residual stenosis after conventional balloon angioplasty for hemodialysis shunt failure: treatment with metallic stent placement and post-balloon dilatation.

PURPOSE: The usefulness of metallic stent placement and post-balloon dilatation was investigated for patients with residual stenosis after conventional percutaneous transluminal balloon angioplasty (balloon PTA) of dialysis shunt vessels. MATERIALS AND METHODS: Among 92 patients who had received balloon PTA for dialysis shunt vessels, seven patients who showed a residual waist on the balloon even under maximum inflation were enrolled in this study. In these patients with residual stenosis after balloon PTA, we inserted a stent in the residual stenosis, and post-balloon dilatation was immediately applied using the same balloon catheter. RESULTS: After balloon PTA, the average percent diameter stenosis declined to 45.5 +/- 7.30%, and the stenosis was further improved to an average of 19.3 +/- 7.09% after the placement of a stent and the additional balloon PTA. The average percent diameter dilatation of the balloon before the placement of a stent was 65.8 +/- 12.7%, while the average dilatation increased to 84.1 +/- 8.96% after the placement of a stent. Dialysis became possible immediately after the procedure in all cases. CONCLUSION: Metallic stent placement and post-balloon dilatation was effective for patients with residual stenosis after conventional balloon PTA of dialysis shunt vessels.

Aged↗
PubMed2005

Multislice computed tomography of pneumoparotid: a case report.

Pneumoparotid is a rare cause of parotid gland swelling that is often misdiagnosed and therefore incorrectly treated. It is the result of an increase in intraoral pressure and the subsequent forced entry of air through Stensen's duct. We report a case of a 15-year-old boy with a history of recurrent swelling of both parotid glands. The final diagnosis of pneumoparotid was established by multislice computed tomography (CT). The clinical presentation, pathogenesis, and radiographic findings are discussed.

Adolescent↗
PubMed2005

[Clinical study of porous gelatin sphere (YM 670) in transcatheter arterial embolization].

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.

Adult↗
PubMed2004

Prediction of outcome of advanced cervical cancer to thermoradiotherapy according to expression profiles of 35 genes selected by cDNA microarray analysis.

PURPOSE: To identify a set of genes related to thermoradiosensitivity of cervical carcinoma and to establish a predictive method. METHODS AND MATERIALS: A total of 19 patients with cervical cancer (1 with Stage IIIA, 11 with Stage IIIB, 5 with Stage IVA, and 2 with Stage IVB) who underwent definitive thermoradiotherapy between May 1995 and August 2001 were included in this study. We compared the expression profiles of 8 thermoradiosensitive and 11 thermoradioresistant tumors obtained by punch biopsy before treatment using a cDNA microarray consisting of 23,040 human genes. RESULTS: We selected 35 genes on the basis of a clustering analysis and confirmed the validity of these genes with a cross-validation test. Some of these genes were already known to be associated with apoptosis (BIK, TEGT, SSI-3), hypoxia-inducible genes (HIF1A, CA12), and tumor cell invasion and metastasis (CTSL, CTSB, PLAU, CD44). We developed a "predictive score" system that could clearly separate the thermoradiosensitive group from the thermoradioresistant group. CONCLUSION: These results from the treatment program between May 1995 and August 2001 showed that by using gene-expression profiles we can predict the outcome of thermoradiotherapy for advanced cervical carcinoma. A "predictive score" system was developed that could clearly separate the thermoradiosensitive group from the thermoradioresistant group. These results may eventually lead to the achievement of "personalized therapy" for this disease.

Adult↗
PubMed2004

Dietary restriction: effects of short-term fasting on protein uptake and cell death/proliferation in the rat liver.

Dietary restriction (DR) is known to prolong life in laboratory animals. Intermittent (alternate-day) fasting or short-term repeated fasting has also been reported to increase the life span of animals. In the present study, we investigated the changes or induction of abnormalities of protein metabolism in rats during fasting, and measured asialoglycoprotein uptake and cell death/proliferation in the liver of rats receiving fasting and refeeding. In the results, liver weight decreased significantly after 48 h of fasting and increased during the refeeding period, returning to the pre-fasting level by 12 h of refeeding. Cell death, determined by single stranded DNA (ssDNA) staining method, increased during the fasting period, and returned to the pre-fasting level during the refeeding period. Cell proliferation, determined using antibodies (Ab) against proliferating cell nuclear antigen, decreased during the fasting period, and increased during the refeeding period. Changes in cell death and cell proliferation were inversely related. However, there was no significant difference in asialoglycoprotein uptake by the whole liver between the ad libitum (AL)-fed rats and 48 h fasted rats. Thus, neither the changes in liver weight nor cell death/proliferation affected asialoglycoprotein uptake on a living body. These results suggest that episodes of 48 h fasting do not induce protein metabolism abnormalities in the liver.

Animals↗
PubMed2004

Subtle disruption of the middle cerebellar peduncles in patients with schizophrenia.

Diffusion tensor imaging (DTI) was used to investigate subtle disruption in the middle cerebellar peduncles in patients with schizophrenia. Fractional anisotropy (FA) was measured in 25 patients with schizophrenia and 21 healthy subjects using DTI. The FA of the right and left middle cerebellar peduncles was significantly lower in the schizophrenic patients compared to healthy subjects. FA in the left middle cerebellar peduncles was significantly correlated with the dosage of neuroleptics in patients with schizophrenia. There were no significant differences of mean diffusivity in the right and left middle cerebellar peduncles between patients with schizophrenia and healthy subjects. The findings of the study suggest that antipsychotics may improve the subtle disruption in the middle cerebellar peduncles in patients with schizophrenia.

Adult↗