Akihisa Ueno

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PURPOSE To compare image quality obtained in phantoms with virtual monochromatic spectral (VMS) imaging with that obtained with conventional 120-kVp computed tomography (CT) for a given radiation dose. MATERIALS AND METHODS Three syringes were filled with a diluted contrast medium (each syringe contained a contrast medium with a different iodine(More)
BACKGROUND & AIMS In the current era of emerging molecular targeted drugs, it is necessary to identify before treatment the specific subclass to which a tumour belongs. Gadoxetic acid is a liver-specific contrast agent that is preferentially taken up by hepatocytes. Therefore, gadoxetic acid-enhanced magnetic resonance imaging (EOB-MRI) should provide(More)
We report a case of concomitant pancreatic endocrine neoplasm (PEN) and intraductal papillary mucinous neoplasm (IPMN). A 74-year-old man had been followed-up for mixed-type IPMN for 10 years. Recent magnetic resonance images revealed an increase in size of the branch duct IPMN in the pancreas head, while the dilation of the main pancreatic duct showed(More)
PURPOSE We assessed what MR imaging parameters affected ringing artifacts during the arterial phase of gadoxetic acid-enhanced dynamic magnetic resonance (MR) imaging. MATERIALS AND METHODS We tested various parameters, including imaging matrices, choice of either sequential or elliptical centric phase-encoding scheme, scanning time, and contrast(More)
PURPOSE Hypovascular nodules that exhibit hypointensity in hepatocyte-phase images of gadoxetic acid-enhanced magnetic resonance (MR) imaging are frequently encountered in clinical practice. We investigated risk factors for the development of these nodules into hypervascular hepatocellular carcinoma (HCC). METHODS We retrospectively reviewed our(More)
OBJECTIVE To compare the diagnostic characteristics of the evaluation of myometrial invasion (MI) retrospectively between preoperative magnetic resonance imaging (MRI) and intraoperative frozen sections. DESIGN A retrospective study. SETTING University hospital. SAMPLE 201 women diagnosed with endometrial carcinoma. METHODS All women underwent(More)
We have described and criticized the methods, techniques and materials used in our laboratory to obtain arterial and venous pressures, arterial and venous blood flows, cardiac output, internal diameter and pressure of the left ventricle, ECG and vascular diameters in unanesthetized and unrestrained dogs using both radiotelemetering systems and a direct wire(More)
Lymphoepithelioma-like hepatocellular carcinoma (LEL-HCC) is a rare form of undifferentiated carcinoma of the liver characterized by the presence of an abundant lymphoid infiltrate. Here, a case of LEL-HCC is described. An 81-year-old woman with a chronic hepatitis C infection was referred to the general surgery department of our hospital in August 2013(More)
The purpose of this study was to evaluate whether experimental fine-cell detector computed tomography with a 0.3125 mm cell (0.3 mm cell CT) can improve the detection of coronary vessel walls compared with conventional 64-slice computed tomography with a 0.625 mm cell (0.6 mm cell CT). A coronary vessel wall phantom was scanned using 0.6 mm cell CT and 0.3(More)
An 83-year-old man underwent computed tomography during a routine check-up due to a history of surgical treatment for pancreatic cancer. Two tumors were detected in the anterior segment of the liver. A needle biopsy of the larger tumor was performed, and pathological examination showed that the tumor was a poorly differentiated hepatocellular carcinoma.(More)