Inguinal dedifferentiated liposarcoma with meningothelial-like whorls and metaplastic bone formation.
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Calcinosis↗
Biomedical subjects
A Arakawa
Publications and source records attributed to A Arakawa.
Visual disturbance due to retinal edema as a complication of imatinib.
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Adult↗
Duodenal wall cysts may be derived from a ductal component of ectopic pancreatic tissue.
AIMS: To clarify the mechanism of origin of duodenal wall cysts in patients with chronic pancreatitis, developing into duodenal stenosis. METHODS AND RESULTS: Specimens from 12 pancreatoduodenectomized patients with chronic pancreatitis and 51 controls were studied histopathologically and immunohistochemically. Variously shaped cystic lesions, averaging about 15 mm in diameter, were found in the duodenum in six of the 12 patients with chronic pancreatitis, but were not observed in the controls. Each case had an average of two cysts, which were located mainly in the muscularis propria of the duodenum with or without submucosal or extraduodenal-peripancreatic extensions. The inner part of the cyst wall consisted of a moderate rim of granulation tissue, with both myofibroblasts and smooth muscle proliferation in the tissue surrounding the cyst and the submucosal layer of the duodenum, occasionally accompanied by an epithelial lining. A ductal structure in the muscularis propria of the duodenum, possibly a ductal component of ectopic pancreatic tissue, was found in five of the six cases. Some of these structures showed cystic changes. Three of the six patients had accompanying duodenal stenosis. CONCLUSIONS: Duodenal wall cysts occur mainly in the muscularis propria of the duodenum associated with both myofibroblasts and smooth muscle proliferation, and may result in duodenal stenosis. These cysts may be derived from a ductal component of ectopic pancreatic tissue.
Adult↗
Pharmacokinetic and pharmacodynamic analysis of combined chemotherapy with carboplatin and paclitaxel for patients with ovarian cancer.
BACKGROUND: This study was conducted to assess the utility of pharmacokinetic and pharmacodynamic analyses of carboplatin (CBDCA) and paclitaxel (TAX) employed for chemotherapy in ovarian cancer patients. METHODS: The pharmacokinetics and pharmacodynamics of chemotherapy with CBDCA and TAX were analyzed in 13 patients with ovarian cancers. The pharmacodynamic model, based on myelosuppression, was assessed in terms of concentrations of free platinum (free-Pt) and TAX in blood samples. TAX (175 mg/m2) was administered intravenously (i.v.) over 3 h, and CBDCA (target area under the concentration curve [AUC], 5 mg/ml x min) over 1 h. Free-Pt and TAX concentrations in blood samples were measured at several time points after administration. RESULTS: The nadirs of both the leukocyte and neutrophil counts correlated significantly with the TAX AUC (AUCtax) and serum albumin level, and the percentage decrease in platelet count (pd-Plt) correlated significantly with AUCtax, free-Pt AUC (AUCpt), and the serum albumin level. A pharmacodynamic model corresponding to the nadirs of leukocytes and neutrophils and to pd-Plt was thus generated. CONCLUSION: This pharmacodynamic model may allow the ready prediction, from AUCtax, AUCpt, and the serum albumin value, of the degree of myelosuppression with combined CBDCA and TAX chemotherapy.
Adult↗
Improved tissue characterization of focal liver lesions with ferumoxide-enhanced T1 and T2-weighted MR imaging.
The purpose of our study was to evaluate the potential value of ferumoxide-enhanced T1-weighted magnetic resonance (MR) imaging for tissue characterization of focal liver lesions when combined with T2-weighted sequences. Images were acquired within 30 minutes after the end of ferumoxide administration, when ferrite particles were not totally cleared from the intravascular compartment. Thirty-eight patients with 47 focal liver lesions underwent T1-weighted gradient-echo (TR/TE 150/4.1 msec) and T2-weighted fast spin-echo (3180-8638/90 msec) MR imaging at 1.5 T before and after intravenous administration of ferumoxides (10 micromol/kg body weight). A qualitative and quantitative analysis was performed. During the early phase after infusion of ferumoxide, blood vessels showed hypersignal intensity on T1-weighted fast low-angle shot (FLASH) images, while liver signal decreased. Hemangiomas showed both homogeneous and inhomogeneous enhancement patterns, and liver metastasis most typically showed ring enhancement. Hypervascular tumors (hepatocellular carcinomas and focal nodular hyperplasias) showed a slight degree of homogeneous enhancement. Quantitatively, the degree of enhancement and lesion-to-liver contrast on ferumoxide-enhanced images were significantly different among these tumors. Our results demonstrate that distinct enhancement patterns obtained on ferumoxide-enhanced T1-weighted MR imaging improve tissue characterization of focal liver lesions when combined with T2-weighted images.
Adult↗
Appropriate use of ultrasonography in the neck.
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Humans↗
Application of a biomagnetic measurement system (BMS) to the evaluation of gastrointestinal transit of intestinal pressure-controlled colon delivery capsules (PCDCs) in human subjects.
PURPOSE: For determination of the transit time through various parts of the gastrointestinal (GI) tract, we developed a method that provides the location of disintegration and drug release. This method involves GI magnetomarkergraphy (GIMG) using a 129-channel Shimadzu vector biomagnetic measurement system (BMS). METHODS: To magnetically label the pressure-controlled colon delivery capsule (PCDC) containing 75.0 +/- 0.5 mg of caffeine as a tracer drug, small capsule caps containing 90 mg of ferric oxide powdered magnetite (Fe2O3) were attached to PCDCs. After orally administration to fasted human volunteers, saliva samples were collected hourly and salivary caffeine concentration was measured. At the same time, locations of the magnetic PCDC were detected by BMS just after the PCDCs were magnetized with the coils of a magnetic resonance imaging (MRI) system. The magnetic field distributions were analyzed and the estimated positions were shown on the MRI picture of the same subject's abdominal structure. RESULTS: We magnetized PCDC with permanent magnets or an electromagnet before ingestion and the estimated locations of PCDC in the GI tract exhibited high estimation error. In order to increase the precision of estimated localization of PCDCs, PCDCs were magnetized within the coils of the MRI. As a result, these PCDCs had strong magnetic dipoles that were parallel to the sensor unit of BMS in every measurement, and therefore the spatial resolution of the PCDC's two-dimensional positions in the organs of the GI tract was within a range of several millimeters. CONCLUSIONS: GIMG is a powerful tool for the study of colon delivery efficiencies of PCDCs. The main advantage of GIMG is the capability to obtain even more detailed knowledge of the behavior and fate of solid pharmaceutical formulations during GI passage.
Abdomen↗
Moving mesh method for reconstructing some spread sources in the brain.
The purpose of this paper is to propose a new algorithm for the analysis of biomagnetic field data obtained from magnetoencephalography (MEG) measurements. This new method overcomes two major problems faced by the current method of data analysis. The first problem is the need to determine the number of sites of brain activity before calculations can be performed. The second problem is inability of the analysis to provide any information regarding the volume of the brain activity. The new data analysis method, called the Moving Mesh Method (MMM), is capable of analyzing MEG data without the need to determine the number of sources beforehand. In addition, the MMM determines the location of brain activity as a three dimensional volume, instead of as a point source of activity. The MMM uses an iterative method of calculating the position of the sources to achieve greater accuracy, and a regularized g-inverse matrix to stabilize its solution. The feasibility of the MMM was examined by two methods. First, a computer simulation was used to confirm the MMM's capability to analyzing MEG data. In the second experiment, the MMM was applied to analyze somatosensory evoked fields obtained using a new imaging system (Shimadzu Biomagnetic Imaging System, Model-100). From the interpretation of the results, we have concluded that the MMM is a feasible method of biomagnetic data analysis.
Algorithms↗
Intraductal papillary tumors of the pancreas. Histopathologic correlation of MR cholangiopancreatography findings.
PURPOSE: To evaluate MR cholangiopancreatography (MRCP) findings of intraductal papillary tumors of the pancreas and correlate them with histopathology. MATERIAL AND METHODS: Seventeen patients with intraductal papillary tumor of the pancreas underwent MRCP before surgery. MRCP findings were correlated to histopathology with regard to the presence of septa and excrescent nodules in the cystic lesion, communication between the cystic lesion and the main pancreatic duct (MPD), degree of dilatation of MPD, and dilatation of the common bile duct (CBD). RESULTS: MRCP demonstrated septa in 17 cases (100%), excrescent nodules in 8 cases (47.1%), communication between the intraductal papillary tumor and the MPD in 14 cases (82.3%), dilatation of MPD over 50% in 6 cases (35.3%), and dilatation of CBD in 3 cases (17.6%). These findings showed excellent correlation with histopathology. The septum on MRCP corresponded with a layer of connective tissue with pancreatic duct epithelium. Excrescent nodules in the carcinomas consisted not only of malignant cells, but also of dysplasia and adenoma. Excrescent nodules in adenomas were consistent not only with minimal papillary growth of adenoma, but also with proliferation of fibrosis, and hematoma and organized fibrin with minimal fibrosis. Pancreatic tissue was affected by chronic pancreatitis in all cases. Cases with dilatation of CBD on MRCP were due to microscopic invasion by the carcinoma. CONCLUSION: MRCP appearances of intraductal papillary tumors are well correlated with the findings at histopathology.
Adenocarcinoma, Papillary↗
Diagnostic accuracy of helical CT arterial portography and CT hepatic arteriography for hypervascular hepatocellular carcinoma in chronic liver damage. An ROC analysis.
PURPOSE: To evaluate the detectability of hypervascular hepatocellular carcinomas (HCCs) in chronic liver damage with helical CT arterial portography (CTAP) and CT hepatic arteriography (CTHA). MATERIAL AND METHODS: Thirty-nine HCC patients who underwent CTAP and CTHA were studied. Diagnostic abilities of CTAP alone, CTHA alone, or combined CTAP and CTHA were evaluated by receiver operating characteristic (ROC) analysis. Fifty-three images with 53 HCC nodules were evaluated. Tumor size ranged from 5 to 90 mm (mean 22.8 mm). Sensitivities and specificities for all techniques were calculated. RESULTS: ROC analysis showed the diagnostic ability significantly better with combined CTAP and CTHA (mean area under the ROC curve (Az)=0.95), or CTHA alone (Az=0.93) than CTAP alone (Az=0.87) (p<0.01). Combined CTAP and CTHA showed the best sensitivity (95.0%), followed by CTHA alone (88.1%) and CTAP alone (85.5%). The specificities of all three imaging techniques were relatively low (54.1% for combined CTAP and CTHA, 71.1% for CTHA alone, and 54.1% for CTAP alone) because of perfusion abnormalities of the liver parenchyma. CONCLUSION: The combination of CTAP and CTHA is superior to CTAP alone for detection of hypervascular HCCs. However, its specificity was relatively low in chronic liver damage.
Aged↗
Pancreaticobiliary ductal system: value of half-Fourier rapid acquisition with relaxation enhancement MR cholangiopancreatography for postoperative evaluation.
PURPOSE: To assess the usefulness of half-Fourier rapid acquisition with relaxation enhancement (RARE) magnetic resonance cholangiopancreatography (MRCP) for evaluation of postoperative changes in the pancreaticobiliary ductal system. MATERIALS AND METHODS: The study included 34 patients (20 men, 14 women; mean age, 65.5 years) who underwent surgery of the pancreaticobiliary ductal system. Half-Fourier RARE MRCP images were obtained after surgery. Qualitative evaluation included ratings by two observers for depiction of postoperative anatomy and for artifacts, as well as analysis of postoperative complications. Direct cholangiographic, computed tomographic, and ultrasonographic findings and 6-month follow-up results were the reference standard. Sensitivity, specificity, and accuracy were calculated for the evaluation of postsurgical complications seen at half-Fourier RARE MRCP. RESULTS: The sensitivity, specificity, and accuracy of MRCP for the evaluation of postsurgical complications were each 100% for ductal dilatation; 100%, 87%, and 89%, respectively, for choledochoenteric anastomotic stricture; 100%, 86%, and 87%, respectively, for pancreaticoenteric anastomotic stricture; 100% each for intraductal stones and anastomotic leakage; and 80%, 100%, and 94%, respectively, for cholangitis. CONCLUSION: Half-Fourier RARE MRCP is a reliable imaging technique for the evaluation of anatomy and of complications associated with a surgically altered pancreaticobiliary ductal system.
Adult↗
Ultrasound biomicroscopic analysis of the human ciliary body after 1 and 2% pilocarpine instillation.
We examined ciliary body thickness (CBT) of 11 human eyes after 1% followed by 2% pilocarpine instillation using ultrasound biomicroscopy. The examination revealed that CBT decreased in 2 eyes after 1% pilocarpine treatment but increased after 2% pilocarpine. In the eyes with decreased CBT by 1% pilocarpine, the pretreatment ciliary bodies were thicker and the changing rate of CBT induced by 2% pilocarpine, although not decreased, was also smaller than that in CBT-increased eyes. These findings showed that the ciliary body was under relatively strong stimulus of endogenous acetylcholine and has subsensitivity to both 1 and 2% pilocarpine in CBT-decreased eyes. Configurative changes in CBT-decreased eyes may be explained by the localization of different muscarinic receptor subtypes in different portions of the ciliary muscle.
Adult↗
Descending thoracic aortic aneurysm: thoracic CT findings after endovascular stent-graft placement.
PURPOSE: To evaluate the usefulness of thoracic computed tomography (CT) after placement of an endovascular stent-graft for the treatment of descending thoracic aortic aneurysm. MATERIALS AND METHODS: From 1992 to 1996, 85 patients with thoracic aortic aneurysm underwent stent-graft placement. In 63 patients, thoracic CT scans were obtained both before and within 10 days after placement. The CT findings were retrospectively studied, and their clinical effect analyzed. In 20 of 63 patients, long-term follow-up CT findings were also evaluated. RESULTS: After stent-graft placement in the 63 patients, CT demonstrated an increase in pleural effusion in 46 (73%), periaortic changes in 21 (33%), perigraft leak in 13 (21%), atelectasis in six (10%), mural thrombus within the stent-graft in two (3%), and new aortic dissection in one (2%). The mean maximum diameter of the aneurysm was 58.8 mm before and 60.0 mm after stent-graft insertion. Sixty-two (98%) patients were successfully treated until discharge. Interventional procedures were performed to eliminate the leakage into the aneurysm sac in 10 patients with perigraft flow depicted at CT. Other complications were managed conservatively. CONCLUSION: Thoracic CT is useful in the treatment of patients after stent-graft insertion for the management of descending thoracic aortic aneurysm.
Adult↗
Detection of hepatocellular carcinoma arising in cirrhotic livers: comparison of gadolinium- and ferumoxides-enhanced MR imaging.
OBJECTIVE: We prospectively compared the detectability of hepatocellular carcinoma (HCC) arising in cirrhotic livers using dynamic gadolinium-enhanced fast low-angle shot (FLASH), ferumoxides-enhanced T2-weighted turbo spin-echo, and ferumoxides-enhanced T2*-weighted FLASH MR imaging. SUBJECTS AND METHODS: Fifty-three patients with HCC (32 men and 21 women) who were 33-86 years old (mean, 63 years old) were enrolled in a prospective MR study to assess hepatic lesions using both gadopentetate dimeglumine and ferumoxides. Dynamic gadolinium-enhanced imaging was obtained before and 30, 60, and 180 sec after rapid bolus injection of gadopentetate dimeglumine (0.1 mmol/kg). Ferumoxides-enhanced T2-weighted turbo spin-echo imaging and ferumoxides-enhanced T2*-weighted FLASH imaging were performed between 30 min and 2 hr after i.v. infusion of ferumoxides (10 micromol/kg). Images were analyzed qualitatively and quantitatively. A receiver operating characteristic curve study was performed to compare the diagnostic value of gadolinium-enhanced imaging with that of ferumoxides-enhanced imaging for the detection of HCC. RESULTS: Quantitative analysis revealed a significantly higher percentage of signal-intensity loss and higher liver-lesion contrast-to-noise ratio on ferumoxides-enhanced T2*-weighted FLASH imaging than on ferumoxides-enhanced T2-weighted turbo spin-echo imaging. The percentage of signal-intensity loss and liver-lesion contrast-to-noise ratio on ferumoxides-enhanced images was significantly higher in patients with mild liver cirrhosis (Child's class A) than in patients with severe liver cirrhosis (Child's class C). Qualitative analysis showed that dynamic gadolinium-enhanced images revealed significantly higher lesion conspicuity than did ferumoxides-enhanced T2-weighted turbo spin-echo images. According to receiver operating characteristic analysis, dynamic gadolinium-enhanced FLASH imaging achieved the highest sensitivity, and ferumoxides-enhanced T2*-weighted FLASH imaging was the second most sensitive. We found that ferumoxides-enhanced turbo spin-echo imaging was the least valuable technique for revealing HCC lesions. Gadolinium-enhanced imaging revealed more HCC lesions than did ferumoxides-enhanced imaging, particularly for lesions smaller than 2 cm in diameter. CONCLUSION: Ferumoxides-enhanced imaging revealed fewer findings, such as lesion conspicuity of HCCs arising in cirrhotic livers, than did gadolinium-enhanced FLASH imaging.
Adult↗
[Usefulness of DIC-CT in choledocholithiasis].
In order to assess the efficacy of helical CT in drip-infusion cholangiography (DIC-CT) for diagnosis of choledocholithiasis, 82 patients with biliary diseases, including 25 patients with a definite diagnosis of choledocholithiasis obtained by direct cholangiography, were investigated by DIC-CT and EUS. Comparative investigation showed that, of the 25 cases, 94.7% could be imaged by DIC-CT and 87.5% by EUS, with respective sensitivities of 94.7% and 87.5%. The specificities in both cases were 100% and accuracies were 97.8% with DIC-CT and 96% with EUS respectively. Therefore, in diagnosis the choledocholithiasis, DIC-CT displays similar diagnostic efficiency as EUS or ERC, and can be recognized as the non-invasive and useful procedure for pre-operative diagnosis of cholecystolithiasis.
Biliary Tract Diseases↗
Ultrasound biomicroscopic analysis of anterior proliferative vitreoretinopathy.
PURPOSE: To report the use of ultrasound biomicroscopy for preoperative assessment of anterior proliferative vitreoretinopathy. METHODS: Case report. In a 35-year-old man with tractional retinal detachment and anterior proliferative vitreoretinopathy, we used ultrasound biomicroscopy with UX-02 (Rion Co Ltd, Tokyo, Japan) to perform the preoperative analysis of the ciliary body, anterior vitreous, and detached peripheral retina. RESULTS: In all meridians, the posterior insertion of the vitreous was drawn anteriorly, creating a retinal trough, and the meridian distance between the anterior and posterior vitreous base insertions was reduced. Retinochoroidal detachment was detected posterior to the anterior vitreous base insertion. Based on these imagings, sclerotomy locations were selected. CONCLUSION: Ultrasound biomicroscopy may be useful to assess anterior proliferative vitreoretinopathy preoperatively and to decide on sclerotomy sites.
Adult↗
Clinical and pathological significance of the level and extent of capsular invasion in clinical stage T1-2 prostate cancer.
This study was performed to assess the relationship between the level and extent of prostatic capsular invasion (PCI) by cancer and the clinical and pathological features and prognosis of early-stage prostate cancer. We conducted a retrospective analysis of the clinical (age, stage, grade, prostate specific antigen [PSA] level) and pathological (tumor volume, stage, grade, surgical margins) features of 688 patients treated with radical prostatectomy to determine the pathological features and probability of recurrence associated with various levels of PCI. Radical prostatectomy specimens were serially sectioned and examined by whole-mount technique. Progression-free probabilities (PFP) after radical prostatectomy were determined by Kaplan-Meier and Cox proportional hazards regression analysis. Progression was defined as a rising serum PSA < or = 0.4 ng/mL or clinical evidence of recurrent cancer. Increasing clinical stage, Gleason grade in the biopsy specimen, and pretreatment serum PSA levels were each associated with increasing levels of PCI (P < .001). In the radical prostatectomy specimen, increasing levels of PCI were significantly associated with increasing tumor volume (P < .001), Gleason grade (P < .0001), seminal vesicle involvement (SVI, P < .001) and lymph node metastases (+LN, P < .001). None of 138 patients without capsular invasion had SVI or lymph node metastases (+LN), and all remained free of progression, even though some had large volume (up to 6.26 cm3) or poorly differentiated (Gleason sum up to 8) cancers. Invasion into the capsule (n = 271) was occasionally associated with SVI (6%) or +LN (3%) and a significantly (log-rank test) lower PFP of 87% at 5 years. Focal and extensive extraprostatic extension (EPE) were associated with progressively increased risk of SVI and +LN and lower PFP (73% and 42%, respectively). In a multivariate analysis, the level of PCI was an independent prognostic factor (P < .001). There is a strong association between the level of invasion of cancer into or through the prostatic capsule and the volume, grade, pathological stage, and rate of recurrence after radical prostatectomy. Prostate cancer does not appear to metastasize in the absence of invasion into the capsule regardless of the volume or grade of the intracapsular tumor. Subclassification of patients according to the levels of PCI provides valuable prognostic information.
Adenocarcinoma↗
Helium gas microbubbles. Experimental study on a new ultrasound contrast material.
PURPOSE: To evaluate histological changes and duration of enhancement after the intra-arterial injection of helium gas microbubbles in comparison with conventionally used carbon dioxide (CO2) microbubbles at US. MATERIAL AND METHODS: Four different doses of helium gas microbubbles (0, 0.1, 0.2 and 0.5 ml/kg) mixed with normal saline and own blood were injected into the celiac artery of 8 rabbits. After one week, autopsies were performed on all animals and histological changes in the liver, stomach and spleen were studied on hematoxylin-eosin stains. In addition, VX-2 tumor strains were transplanted into the femoral muscle in 5 other rabbits. Four weeks after transplantation, we catheterized the femoral artery and either CO2 or helium gas microbubbles were injected under US observation. We evaluated the duration of enhancement in the tumors with the two types of microbubbles. RESULTS: On histological evaluation, damage in hepatic cells as well as multiple areas of gastritis in the stomach were seen when a dose of 0.5 ml/kg of helium gas was used. Damage in the liver and stomach was slight at a dose of 0.2 ml/kg. The spleen was not damaged at doses of under 0.5 ml/kg. In the evaluation of tumor enhancement, the duration of enhancement with helium gas microbubbles ranged from 28 to 45 min (average 36 min) while that with CO2 ranged from 4 to 12 min (average 9 min) (p<0.01 at paired t-test). CONCLUSION: Intra-arterial injection of helium gas should not exceed 0.2 ml/kg: a dose of 0.5 ml/kg may cause damage to the liver and stomach. The duration of enhancement with helium gas microbubbles is significantly longer than that with CO2 microbubbles.
Animals↗