Yoshiharu Higashida

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The purpose of this study was to develop a computerized method for detection of multiple sclerosis (MS) lesions in brain magnetic resonance (MR) images. We have proposed a new false positive reduction scheme, which consisted of a rule-based method, a level set method, and a support vector machine. We applied the proposed method to 49 slices selected from 6(More)
RATIONALE AND OBJECTIVES An automated method for identification of patients with cerebral atrophy due to Alzheimer's disease (AD) was developed based on three-dimensional (3D) T1-weighted magnetic resonance (MR) images. MATERIALS AND METHODS Our proposed method consisted of determination of atrophic image features and identification of AD patients. The(More)
PURPOSE To evaluate diagnostic accuracy with unenhanced and superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance (MR) imaging for detection of hepatocellular carcinoma (HCC) in cirrhotic livers. MATERIALS AND METHODS Fifteen patients with 26 histologically proved HCCs associated with liver cirrhosis underwent imaging with T1-, T2-, and(More)
PURPOSE The purpose of this study was to assess the value of three-dimensional fast imaging with steady-state precession (FISP) MR sequences relative to contrast-enhanced CT and spin-echo MR imaging in the diagnosis of carotid cavernous fistula (CCF). METHODS Seventeen patients with 19 angiographically proved CCFs had contrast-enhanced CT, spin-echo MR(More)
PURPOSE To determine the accuracy of transvaginal ultrasound (TVUS) and of precontrast and contrast material-enhanced magnetic resonance (MR) imaging in the differentiation of adnexal masses. MATERIALS AND METHODS Five blinded readers analyzed images of 80 masses in 72 patients. MR and TVUS images were interpreted in separate sessions. Findings were(More)
PURPOSE To assess the diagnostic accuracy of three-dimensional (3D) magnetic resonance (MR) images in the preoperative evaluation of hemifacial spasm. MATERIALS AND METHODS In 27 patients with surgically confirmed hemifacial spasm, the axial source images from 3D time-of-flight MR angiography were evaluated for 27 symptomatic sides and 26 asymptomatic(More)
It has been reported that the severity of subcortical vascular dementia (VaD) correlated with an area ratio of white matter hyperintensity (WMH) regions to the brain parenchyma (WMH area ratio). The purpose of this study was to develop a computer-aided evaluation method of WMH regions for diagnosis of subcortical VaD based on magnetic resonance (MR) images.(More)
BACKGROUND AND PURPOSE Previous studies have suggested that use of an artificial neural network (ANN) system is beneficial for radiological diagnosis. Our purposes in this study were to construct an ANN for the differential diagnosis of intra-axial cerebral tumors on MR images and to evaluate the effect of ANN outputs on radiologists' diagnostic(More)
We investigated the potential clinical use of single-screen/single-emulsion film systems by comparing their relative speeds, modulation transfer functions (MTFs), Wiener spectra, and H & D curves with those of conventional screen-film systems. The relative speeds of single screens with single-emulsion Kodak OM film (single systems) were 50-60% lower than(More)
Observer performance tests were conducted to compare the effects of image-processing technique (unsharp mask filtering) on the diagnostic accuracy of computed radiography (CR) with storage phosphors in the detection of microcalcifications. Comparison of detectability of microcalcifications with CR and with screen-film mammography was also performed.(More)