Hideo Onitsuka
Kyushu University
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Featured researches published by Hideo Onitsuka.
Journal of Computer Assisted Tomography | 1993
Hiroshi Honda; Hideo Onitsuka; Koutarou Yasumori; Takamoto Hayashi; Kouichirou Ochiai; Masaki Gibo; Eisuke Adachi; Takashi Matsumata; Kouji Masuda
To elucidate the characteristic CT findings of intrahepatic peripheral Cholangiocarcinoma, two-phased dynamic incremental CT scans of 20 cholangiocarcinomas in 16 patients were carefully analyzed. Dynamic incremental CT scanning was performed after intravenous administration of 100 ml iodinated contrast medium at a rate of 2 ml/s using a power injector. The CT scans (8–16 sections) were obtained during 45–110 s (early phase) and 6–7 min (delayed phase) after commencement of the injection of the contrast medium. On CT, 55% (11 of 20) of intrahepatic peripheral cholangiocarcinomas appeared hypo-dense in both phases. Most of the tumors (80%) appeared hypodense in the early phase and had increased CT numbers in their delayed images. Lymphadenopathy was observed in 69% (11 of 16) of patients whose main tumors exceeded 3 cm in diameter. All tumors appeared irregular or indistinct. Twenty percent (4 of 20) of the cholangiocarcinomas were difficult to distinguish from hepatocellular carcinomas or hemangiomas.
Radiology | 1977
Hideo Onitsuka
A review of radiographs of 143 Adult Health Study and 46 non-sample subjects made over a period of 23 years established sites, sizes, ages at detection, and prevalence of 209 bone islands in 189 subjects. Except for 18 new bone islands, all appeared during the period of observation. Twenty-six of them changed: of these, 21 enlarged, 4 became smaller, and 1 disappeared. There was no association with atomic bomb radiation dose. Bone islands were more frequent in the pelvis and femora but often occurred in the ribs. Five bone islands in adolescents enlarged proportionally to bone growth, suggesting that they often participate metabolically in the normal osseous system. Bone islands must be differentiated from osteoblastic metastases.
Journal of Computer Assisted Tomography | 2003
Akihiro Nishie; Kengo Yoshimitsu; Hiroyuki Irie; Tadamasa Yoshitake; Hitoshi Aibe; Tsuyoshi Tajima; Kenji Shinozaki; Tomohiro Nakayama; Daisuke Kakihara; Takashi Matsuura; Makoto Takahashi; Noriyuki Kamochi; Hideo Onitsuka; Hiroshi Honda
Objectives To clarify radiologic findings of Fitz-Hugh-Curtis syndrome (FHCS). Methods Thirteen women with right upper abdominal pain who were clinically diagnosed with FHCS were included. Biphasic helical computed tomography (CT) of the abdomen was performed in all patients. Posttherapeutic follow-up CT was available in 7 patients. Ultrasonography (US) was also performed in 12 patients. These imaging findings were reviewed retrospectively. Results On enhanced CT, hepatic and splenic capsular enhancement was identified in 13 and 4 patients, respectively. Hepatic capsular enhancement on the early phase, which was detected in all patients, disappeared after treatment. No adhesive band or fluid collection around the liver was evident. No enhancement of the “bare area” of the liver and spleen was seen. No definite abnormality of the liver or perihepatic region was detected by US. Conclusions Hepatic and splenic capsular enhancement on abdominal enhanced CT may be characteristic of FHCS. Enhanced CT may be a useful and noninvasive modality to help a diagnosis of FHCS, especially in young women with right upper abdominal pain without significant findings on US and gastrointestinal endoscopy.
Abdominal Imaging | 1992
Hiroshi Honda; Hideo Onitsuka; Junji Murakami; Kuniyuki Kaneko; Sadayuki Murayama; Eisuke Adachi; Takashi Kanematsu; Sugimachi K; Kouji Masuda
The sensitivity, specificity, and accuracy of ultrasonography (US), dynamic incremented computed tomography (CT) with delayed phase imaging, and magnetic resonance imaging (MRI) with or without Gd-DTPA were studied for detecting the characteristic appearances of hepatocellular carcinomas (HCC): fibrous capsules, fibrous septa, and mosaic appearances. Results were prospectively evaluated in 30 patients who subsequently underwent hepatic lobectomies or segmentectomies. Pathologic evaluations of the resected liver specimens demonstrated fibrous capsules in 20 tumors (66.7%), fibrous septa in 13 tumors (43.3%), and mosaic appearances in 19 tumors (63.3%). The accuracies for fibrous capsules were 71.4% (20 of 28) for US, 81.5% (22 of 27) for CT, and 92.3% (24 of 26) for MRI. The accuracies for fibrous septa were 57.1% (16 of 28) for US, 59.3% (16 of 27) for CT, and 73.1% (19 of 26) for MRI. The accuracies for mosaic appearances were 71.4% (20 of 28) for US, 51.9% (14 of 27) for CT, and 69.2% (18 of 26) for MRI. Gd-DTPA administrated MRI showed higher accuracies than did conventional MRI for all manifestations. In conclusion, the fibrous capsules of HCCs were readily detected by CT and MRI. Gd-DTPA administration demonstrated an advantage in clarifying fibrous capsules, as well as fibrous septa and mosaic appearances.
Journal of Computer Assisted Tomography | 1993
Hajime Nakata; Kanji Egashira; Hideyuki Watanabe; Katsumi Nakamura; Hideo Onitsuka; Sadayuki Murayama; Junji Murakami; Kouji Masuda
The MR appearance of eight bronchogenic cysts is reported. All the cysts appeared homogeneous and were of very high signal intensity, approximating that of CSF on spin-echo T2-weighted imaging, and of relatively high intensity, between that of muscle and subcutaneous fat on T1-weighted imaging. The cysts were round or ovoid and were well demarcated. These findings are consistent with the fluid-containing properties of cysts.
Journal of Computer Assisted Tomography | 1991
Hiroshi Honda; Hideo Onitsuka; Seiji Naitou; Kanehiro Hasuo; Itsuma Kamoi; Kiyohiko Hanada; Jouichi Kumazawa; Kouji Masuda
The CT and clinical features of six patients with congenital renal arteriovenous malformation (RAVM) were reviewed to determine the characteristics of this condition. The most common symptom was hematuria. The CT images were characterized by masses of vascular density located in the renal sinus and surrounding the pelvicaliceal system with or without dilated renal veins. The exact size of the RAVM and the relation to the pelvicaliceal system were well demonstrated by delayed images or drip infusion technique, whereas the bolus injection technique was essential to document the vascular nature. The potential pitfalls in diagnosis that can occur if only an infusion study is performed are discussed.
Diseases of The Colon & Rectum | 1988
Hideaki Itoh; Shinichi Ikeda; Yoshihiro Oohata; Mitsuo Iida; Tatsunori Inoue; Hideo Onitsuka
Aggressive desmoid tumors present difficult problems among patients with Gardners syndrome. Recently, attention has been directed toward metabolic or hormonal manipulation of these tumors. A 21-year-old woman with Gardners syndrome was admitted because of recurrent abdominal wall tumors. She was treated with nonsteroidal anti-inflammatory drugs, tamoxifen, and ascorbate for seven months. During this therapy, CT scan showed a gradual increase in size of the tumors. Subsequent resection of the abdominal tumors and the colon was performed. Although these three types of drugs were administered to prevent postoperative recurrence, an abdominal wall desmoid tumor that invaded the mesentery developed within nine months. The known treatments, that is, chemotherapy, irradiation, and surgical resection are discussed in view of this experience.
Journal of Thoracic Imaging | 1991
Hideo Onitsuka; Masaaki Tsukuda; Akiteru Araki; Junji Murakami; Yoshikuni Torii; Kouji Masuda
When central lung tumor is associated with lobar collapse, discrimination of tumor from atelectasis is important for determining operability or for field planning should radiation therapy be utilized. Because tumor and collapsed lung have similar attenuation values, they cannot always be distinguished with usual contrast-enhanced CT. The article describes separation of tumor from collapsed lung by means of RSCT with bolus injection of nonionic contrast medium. With this technique collapsed lung is appreciably enhanced, but tumor enhancement is slow and minimal. The difference is most marked from 40 seconds to 2 minutes after scanning begins. This phenomenon is probably related to the marked increase in blood flow per unit area of collapsed lung due to crowding of relatively large pulmonary arteries compared to tumor blood supply through small bronchial arteries. Tumor can also be delineated from atelectasis by differences in internal structure with this technique.
Journal of Computer Assisted Tomography | 1992
Kuniyuki Kaneko; Hideo Onitsuka; Junji Murakami; Hiroshi Honda; Masahiko Kimura; Naotaka Shiraishi; Kouji Masuda
A case of splenic angiosarcoma with siderotic nodules is reported. The tumor was hyperechoic on ultrasound and had high density on CT and very low intensity on MR. Gandy-Gamna nodules (siderotic nodules) were demonstrated histopathogically.
Journal of Trauma-injury Infection and Critical Care | 1998
Sadayuki Murayama; Hideo Onitsuka; Junji Murakami; Yoshikuni Torii; Kouji Masuda; Kazuyoshi Nishihara
Objective The “CT angiogram sign” in dynamic pulmonary CT consists of enhanced branching pulmonary vessels in a homogeneous hypoattenuating consolidation of lung parenchyma and is reportedly useful for diagnosing lobar bronchioloalveolar cell carcinomas. Materials and Methods To identify cases exhibiting the CT angiogram sign, we retrospectively reviewed the reports of 5,500 dynamic incremental CT examinations of the chest. Results We identified the CT angiogram sign in five patients with obstructive pneumonitis due to lung tumors and four patients with pneumonias. Conclusion The CT angiogram sign can be observed in pulmonary consolidation of varying etiologies.