Yoshiro Himeno
Tokyo Medical and Dental University
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Publication
Featured researches published by Yoshiro Himeno.
Journal of Magnetic Resonance Imaging | 2000
Ichiro Yamada; Tsuneaki Nakagawa; Yoshiro Himeno; Yasushi Kobayashi; Fujio Numano; Hitoshi Shibuya
The purpose of the study was to determine the diagnostic accuracy of breath‐hold contrast‐enhanced three‐dimensional (3D) magnetic resonance (MR) angiography in Takayasu arteritis. Thirty patients suspected of having Takayasu arteritis were examined with MR angiography and conventional angiography. Takayasu arteritis was diagnosed in 20 of these patients. MR angiography was performed using a 1.5‐T system after bolus injection of 0.1 mmol/kg of gadodiamide. MR angiography clearly depicted various vascular lesions in the aorta and its major branches in all 20 patients with Takayasu arteritis. It also depicted pulmonary artery lesions in 10 (50%) of the 20 patients. MR angiography accurately depicted 323 (98%) of 330 arteries, but 7 (2%) stenotic arteries were overestimated as occluded. The sensitivity and specificity of MR angiography for the diagnosis of Takayasu arteritis were both 100%. Breath‐hold contrast‐enhanced 3D MR angiography clearly depicts various vascular lesions in both the systemic and pulmonary arteries in Takayasu arteritis, thus allowing a definitive diagnosis of Takayasu arteritis. J. Magn. Reson. Imaging 2000;11:481–487.
Stroke | 2000
Ichiro Yamada; Yoshiro Himeno; Yoshiharu Matsushima; Hitoshi Shibuya
BACKGROUND AND PURPOSE Renal artery lesions in moyamoya disease have been described sporadically in several case reports. The purpose of this study is to evaluate the angiographic findings of renal artery lesions in moyamoya disease and to determine the prevalence of renal artery lesions in patients with moyamoya disease. METHODS Eighty-six consecutive patients with idiopathic moyamoya disease were prospectively examined with both cerebral angiography and abdominal aortography. The findings of abdominal aortography were reviewed for the presence and appearance of renal artery lesions and compared with the clinical data and cerebral angiographic findings. RESULTS Of 86 patients with idiopathic moyamoya disease, 7 patients (8%) were found to have renal artery lesions. Six patients (7%) had stenosis in the renal artery, and 1 patient (1%) had a small saccular aneurysm in the renal artery. Two patients (2%) with a marked renal artery stenosis presented with renovascular hypertension, which resulted in an intraventricular hemorrhage in 1 patient. Furthermore, the renal artery stenosis in the 2 patients with renovascular hypertension was successfully treated with percutaneous transluminal angioplasty. There was no significant correlation between the presence of renal artery lesions and cerebral angiographic findings. CONCLUSIONS Seven (8%) of 86 patients with moyamoya disease showed renal artery lesions, including 6 stenoses (7%) and 1 aneurysm (1%). Renal artery lesions are a clinically relevant systemic manifestation in patients with moyamoya disease.
Journal of Computer Assisted Tomography | 1997
Kaoru Hanafusa; Isamu Ohashi; Naoya Gomi; Yoshiro Himeno; Toshiko Wakita; Hitoshi Shibuya
PURPOSE Our goal was to differentiate between early homogeneously enhancing hepatocellular carcinoma (HCC) and hemangioma by two-phase CT. METHOD Two phase images of 51 HCCs and 28 hemangiomas showing homogeneous high attenuation in the first series (arterial dominant phase) were reviewed. Enhancement patterns of the lesions in the second series (parenchymal phase) were classified as homogeneous high, peripheral high, iso-, and low attenuation. The attenuation values of all and the enhancement values of some (21 HCCs and 18 hemangiomas) in the first series were calculated. RESULTS Although low and peripheral high attenuation patterns were seen during the second series only in HCCs (n = 35), which could be used to correctly diagnose HCC, other nonspecific patterns were demonstrated in both HCCs (n = 16) and hemangiomas (n = 28). The attenuation values of 49 of the 51 HCCs and 5 of the 28 hemangiomas were below 130 HU on the first series. The enhancement values of all 21 HCCs and 3 of 18 hemangiomas were below 70 HU. Combining the enhancement patterns with a borderline attenuation value of 130 HU or borderline enhancement value of 70 HU yielded overall accuracies of 94 and 92%, respectively. CONCLUSION The combined criteria (enhancement pattern plus attenuation or enhancement value) were useful for differentiating between early homogeneously enhancing HCCs and hemangiomas.
Journal of Computer Assisted Tomography | 1997
Isamu Ohashi; Hiroyasu Ina; Kaoru Hanafusa; Tetsuo Yoshida; Yoshiro Himeno; Naoya Gomi; Yoichi Okada; Toshihiko Wakita; Hitoshi Shibuya; Shin-ichi Ohtani
PURPOSE Our goal was to describe the CT findings of aberrant left gastric vein (ALGV) and to evaluate the clinical significance of this vein. METHOD Four patients in whom ALGVs were demonstrated by helical CT were examined. Each patient had either intrahepatic cholangiocarcinoma, cirrhosis with gastric varices, chronic hepatitis, or nonspecific abdominal pain. All patients underwent two phase helical CT, and the patient with cholangiocarcinoma underwent CT during arterial portography, and 3D images of the abdominal veins were obtained. RESULTS In all patients, the ALGVs ran along the hepatogastric ligament and were directly connected with the left portal branch. In the patient with cholangiocarcinoma, the portal vein had severe stenosis by tumor invasion, and both the ALGV and the aberrant right gastric vein functioned as a collateral pathway of the portal flow into the liver. In the patient with cirrhosis, dilated ALGV with hepatofugal flow caused gastric varices. CONCLUSION The ALGV is directly connected with the left portal branch and may play an important role in the collateral pathway of the portal system.
Digestive Diseases and Sciences | 2003
Yoichi Okada; Hiroyasu Ina; Kazunori Kubota; Yoshiro Himeno; Toshihiko Wakita; Isamu Ohashi; Naoya Gomi; Tetsuo Yoshida; Sunao Mae; Tetsuya Irie
We present the survival rates of 75 nonruptured hepatocellular carcinoma cases initially treated with computed tomography-guided transarterial chemoembolization in a single institute. The 1-, 3-, and 5-year survival rates were 93.9%, 74.7%, and 47.4% in 50 Childs A cases; 75.0%, 43.6%, and 6.8% in 20 Childs B cases; and 60.0%, 40.0%, 0.0% in 5 Childs C cases, respectively. The 1-, 3-, and 5-year survival rates of the 38 estimated resectable hepatocellular carcinoma cases (Childs A, tumors limited in a single lobe) were 94.7%, 82.0%, and 44.6%, respectively. The 1-, 3-, and 5-year survival rates of the 41 cases with estimated indication for percutaneous ethanol injection therapy (tumors less than 3 cm in diameter and three or fewer in number) were 96.8%, 84.6%, and 55.5% in 31 Childs A cases; and 90.0%, 46.7%, and 0% in 10 Childs B cases, respectively. In conclusion, computed tomography-guided transarterial chemoembolization is an excellent primary therapy for hepatocellular carcinoma.
Radiology | 1999
Ichiro Yamada; Winn Aung; Yoshiro Himeno; Tsuneaki Nakagawa; Hitoshi Shibuya
Radiology | 1998
Ichiro Yamada; Tsuneaki Nakagawa; Yoshiro Himeno; Fujio Numano; Hitoshi Shibuya
Radiology | 1995
K Hanafusa; I Ohashi; Yoshiro Himeno; Soji Suzuki; Hitoshi Shibuya
Radiology | 1995
I Yamada; Yoshiro Himeno; Soji Suzuki; Yoshiharu Matsushima
Radiology | 1995
I Ohashi; H Ina; N Gomi; Yoshiro Himeno; Y Okada; K Hanafusa; Soji Suzuki; Hitoshi Shibuya