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Ultrasound (US) was compared with mammography (MMG), computed tomography (CT), and digital subtraction angiography (DSA) in its effectiveness to detect breast cancer masses and metastatic axillary nodes. Forty-seven breast cancer patients who all underwent MMG, US, CT, and DSA preoperatively in our institution between 1986 and 1990 were studied. US was able to detect tumors in all cases regardless of tumor size, whereas DSA detected T1-size tumors and MMG detected T2-size tumors in 40% and 64.7% of cases, respectively, being specifically inferior to US. It was found that MMG was least likely to detect papillotubular carcinoma, although microcalcification alone without a tumor mass on MMG improved detectability from 46.2% to 76.9%, according to the histological type. CT was found to be most sensitive to axillary node metastases (81.8%), followed by US (72.7%), but DSA was significantly unfavorable (42.9%). Thus, we concluded that US was superior to MMG, CT, and DSA for detecting breast cancer masses, but that CT was more advantageous than US, while DSA was of little value for evaluating axillary nodal status.

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Objectives The purpose of this study was to clarify the difference in diagnostic accuracy for alveolar bone defects of the mandibular molar region between cone-beam computed tomography (CBCT) and multidetector-row CT (MDCT) by receiver-operating characteristic (ROC) analysis. Methods Artificial alveolar bone defects in a dry human mandible were scanned with a CBCT system (CB MercuRay; Hitachi Medical Corporation) and an MDCT scanner (Aquilion 16-slice; Toshiba Medical Systems Corporation). The field of view (FOV) for the CT images was 5, 10, and 15 cm. Five radiologists observed the obtained DICOM CT images using OsiriX version 3.8.1 (OsiriX Foundation) on an iMac computer (Apple Computer Inc.), and rated the confidence levels for detecting the bone defects using a continuously distributed test. The areas under the ROC curves (Az values) were then calculated with ROCKIT 1.1B (Charles E Metz, The University of Chicago). The significance of differences in the Az values between CBCT and MDCT was tested by the Steel-Dwass method with a significance level of 5 %. Results The overall differences in the Az values between CBCT and MDCT were not significant. However, in the images with 15-cm FOV, the Az value for CBCT was significantly lower than that for MDCT. ConclusionsThe diagnostic accuracy for alveolar bone defects was comprehensively equal between CBCT and MDCT. In CBCT, a large FOV can be avoided to reduce the radiation exposure dose, because enlargement of the FOV does not improve the diagnostic accuracy.

Morphological alterations of the glomerulus were induced by infusion of cationized ferritin. After a direct injection of highly cationized ferritin (CF) into the left kidney of rats, endothelial injuries were followed by activation of platelets and the coagulation system after 1-2h, which occluded capillary loops. In most glomeruli, resolving processes occurred from 2 h onward, leaving a mild thickening of the mesangial region at 7 days. On the other hand, in severely involved glomeruli, capillary loops were still obstructed even at 24 h by hypertrophic and proliferated endothelial cells as well as mesangial cells, instead of platelets and fibrin strands. After this period, exfoliation of podocytes and endothelial cells occurred over a wide area, which resulted in glomerular obsolescence at 7 days. These progressive glomerular injuries were assumed to be closely related to the persistence of CF in glomeruli, which might be caused by disturbances of glomerular clearing systems. Mild proteinuria was only noticed in severely involved cases. It is concluded that an assault on glomerular endothelial cells by cationic macromolecules can cause thrombotic complications leading to glomerular obsolescence.