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Hisao Koga

Publications and source records attributed to Hisao Koga.

5 recordsLinked to original sources
PubMed2006

Assessment of major aortopulmonary collateral arteries with multidetector-row computed tomography.

Multidetector-row computed tomography (MDCT) studies were performed in three adult patients with pulmonary atresia with a ventricular septal defect. In all patients, the native pulmonary arteries were absent, and the pulmonary circulation was totally supplied by major aortopulmonary collateral arteries (MAPCAs). MDCT studies with 1-mm collimation provided detailed information on MAPCAs and bronchial collaterals, such as the numbers and sites of origin, their varying diameters, their courses, and the areas of the lungs they supply. MDCT studies may provide an efficient road map for safe and successful selective catheterization and may substitute for conventional angiography in patients with considerable risks.

Abnormalities, Multiple↗
PubMed2005

Complications of percutaneous radiofrequency ablation for hepato-cellular carcinoma: imaging spectrum and management.

Percutaneous radiofrequency (RF) ablation is feasible for the treatment of unresectable hepatocellular carcinoma, and experience at the authors' institution during 5 years indicates that percutaneous RF ablation can be performed safely in most cases. However, early or late complications related to mechanical or thermal damage may be observed at follow-up examination. Complications may be classified in three groups: vascular (eg, portal vein thrombosis, hepatic vein thrombosis with partial hepatic congestion, hepatic infarction, and subcapsular hematoma), biliary (eg, bile duct stenosis and biloma, abscess, and hemobilia), and extrahepatic (eg, injury to the gastrointestinal tract, injury to the gallbladder, pneumothorax and hemothorax, and tumor seeding). Most complications can be managed with conservative treatment, percutaneous or endoscopic drainage, or surgical repair. Because an early and accurate diagnosis is necessary for proper management, radiologists should be familiar with the imaging features of each type of complication.

Aged↗
PubMed2004

Neuroendoscopic transventricular surgery for suprasellar cystic mass lesions such as cystic craniopharyngioma and Rathke cleft cyst.

Cystic mass lesions in the suprasellar cistern are often associated with neurological deficits, cognitive disorders, and endocrinological impairments. Many surgical approaches are available to treat these mass lesions, but are technically difficult and cannot remove the lesion completely without risking damage to neurological and endocrinological functions due to the proximity to the surrounding structures. Neuroendoscopic transventricular surgery was performed using a ventricular fiberscope for three patients with craniopharyngiomas and two patients with Rathke cleft cysts, with gamma knife radiosurgery for craniopharyngiomas. The endoscopic transventricular approach is safe and minimally invasive for congenital benign suprasellar cystic lesions, especially arachnoid cysts.

Aged↗
PubMed2003

[Neuroendoscopic treatment for Rathke's cleft cyst: transventricular approach to suprasellar cystic lesion].

We report a case of a Rathke's cleft cyst, which was successfully treated by neuroendoscopy. The endoscopic procedure for the intra-suprasellar cystic lesion used the transventricular approach, similar to that of third ventriculostomy. A 66-year-old woman suffered from headache, nausea and constriction of the visual field. Magnetic resonance imaging (MRI) on admission showed an intra-suprasellar cystic lesion. Biopsy of the cyst wall and fenestration of the floor of the third ventricle was performed using an endoscopic transventricular approach. The cyst content was totally aspirated, using a suction system which was connected to the operation channel of the endoscope. The histological diagnosis was Rathke's cleft cyst. No post-operative complication was observed. The endoscopic transventricular approach is safe and most suitable in terms of minimum invasiveness for the intrasuprasellar cystic lesion. We consider that neuroendoscopic transventricular approach will become the common surgical method of choice for treating a suprasellar cystic mass lesion.

Aged↗