[Three-dimensional CT angiography for cerebral aneurysm using a multi-angle reconstruction plan method].

The purpose of this study was to evaluate the clinical usefulness of three-dimensional CT angiography (3D-CTA) for the diagnosis of cerebral aneurysm using a new reconstruction method called Multi-Angle Reconstruction Plan (MARP). The threshold values, region of interest and six angles of view were preset for the MARP method on the basis of our experience with cerebral 3D-CTA. Spiral CT angiography was performed in 27 patients with 29 aneurysms. The six images reconstructed with the MARP method were generated from the volumetric CT data. Two radiologists independently reviewed the six 3D-CT images for the presence of aneurysm. It took about five minutes to semiautomatically reconstruct the six 3D-CT images with the MARP method. There were no discrepancies in the evaluation of the 3D-CT images. Twenty-six aneurysms of 24 patients were demonstrated on the six 3D-CT images. Three aneurysms in 3 patients were not depicted on the 3D-CT images by the MARP method. In them, the additional 3D-CT images which were generated after evaluating the 2D-CT images clearly showed the aneurysms. The MARP method is considered to be a useful three-dimensional reconstruction technique for the diagnosis of cerebral aneurysm.

[Incidental renal cell carcinoma].

We reviewed the cases of incidental renal cell carcinoma that had been treated at the Kitasato University Hospital between July, 1971 and December, 1989. Forty one of the 170 (24.1%) cases were found without any direct signs of renal cell carcinoma. The patients were between 30 and 78 years old (mean 55.0 years) and consisted of 29 males and 12 females. Fifteen cases were detected at the general health check-up and the remaining 26 during the postoperative follow-up for other malignant tumors or other diseases. Twenty three cases were identified by ultrasonography followed by computed tomography (CT) and excretory pyelography in 4 cases each. Especially, the number of patients incidentally found by ultrasonography had increased in the recent 8 years. Urinalysis did not show any microhematuria in 31 of the 37 cases (83.7%), and no tumor mass could be detected by excretory pyelography in 3 cases. We believe that ultrasonography may be valuable as a screening modality for early detection of renal cell carcinoma and should be used as a screening method at the routine health check-up.

[Surgical treatment of renal cell carcinoma with tumor thrombus in inferior vena cava].

Removal of renal cell carcinoma (RCC) extended into the inferior vena cava (IVC) can be a difficult operation. Between 1941 and 1989, 110 RCC patients were treated with radical operation and examined for tumor thrombus histopathologically. Twenty nine (26.3%) patients had invasion into the returning vein of tumor (Stage Vla), 12 (10.9%) in renal vein (stage Vlb) and the remaining 4 (3.6%) into IVC (stage V2). In one patient who had surgery under extracorporeal circulation, a thrombus was extended into the right atrium. In the remaining three patients, the RCC was confined to a small portion of the IVC and operated by caval sleeve resection. Radical operation in such patients free of any distant metastasis, may raise the survival rate.