Masahiko Yamada

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OBJECTIVE The purpose of this study is to compare the accuracy of ultrasound-guided puncture using new real-time 3D (4D) ultrasound and conventional 2D ultrasound for focal hepatic masses using a liver phantom. MATERIALS AND METHODS A 4D ultrasound system equipped with a 5-MHz 4D probe displayed both axial and orthogonal images parallel to a puncture line(More)
AIM To verify whether arterial-phase contrast-enhanced ultrasonography (CEUS) of tumor parenchymal tissue is useful for evaluation of anti-angiogenesis agents. METHODS Rabbits with liver tumor were subjected to CEUS, and images of the nodular maximal diameter in vascular phase were recorded. Image analysis was performed to plot the time intensity curve(More)
AIM To determine whether the findings of microflow imaging (MFI), composed of a flash replenishment and a maximum intensity holding sequence, using contrast-enhanced sonography, correlate with the degree of histological differentiation of hepatocellular carcinoma (HCC). METHODS This study was approved by the institutional review board; patients gave(More)
Heat shock proteins (HSPs) induced by thermal ablation therapy may help presenting tumor antigen to the host immune system and be a valuable adjuvant in the ablation therapy of liver cancer. This paper described our preliminary study on the expression of HSP70 in rabbit liver after contrast-enhanced ultrasound (CEUS) and radiofrequency (RF) ablation.(More)
PURPOSE To investigate the behavior of perflubutane microbubbles outside and inside Kupffer cells during diagnostic ultrasound (US) examination, and to determine the thresholds of the acoustic pressure of different kinds of behavior. METHODS Acoustic behavior of perflubutane microbubbles inside and outside Kupffer cells in an acoustic field induced by a(More)
AIM To compare the difference between tumor-induced lymph node enlargement and inflammation-induced lymph node enlargement by contrast-enhanced ultrasonography and pathological findings. METHODS A model of tumor-induced lymph node metastasis was prepared by embedding a VX2 tumor into the hind paws of white rabbits. A model of inflammation-induced(More)
Flash-replenishment (FR) utilizes destruction of microbubbles in the scan volume by high-power ultrasound and enables to observe reperfusion at a low acoustic power. In this paper, we introduced theoretic equation between probability density function (PDF) of the transit time in the scan volume and time intensity curve (TIC) measured by FR method. From the(More)
A 58-year-old man came to our hospital, complaining of diarrhea and bloody stool of about 2 weeks' duration. Colonoscopic examination showed mucosal edema and bleeding, and irregular ulcer in the transverse colon and sigmoid colon. Laboratory data indicated elevated WBC (22300/mm(3)) and CRP (11.93mg/dl), and hypereosinophilia (30%). We diagnosed ischemic(More)
We report a cased of a 68-year-old man with primary T-cell/histiocyte-rich B-cell lymphoma (T/HRBCL) that arose in the trigeminal ganglion. He had a 30-year history of rheumatoid arthritis and presented with progressive left facial pain that had started 3 weeks earlier. Magnetic resonance imaging (MRI) revealed an enhanced mass in the trigeminal ganglion(More)
A 7-year-old girl with Glanzmann's thrombasthenia (GT) fell and hit her head against a table. Within 2 hours she began to vomit and became drowsy. On admission to our hospital her Glasgow Coma Scale score was 13. Computed tomography (CT) on admission showed acute epidural hematoma in the left posterior fossa. We administered platelets, performed emergent(More)