Ferumoxides is a safe and efficacious contrast agent for the detection of focal liver lesions on T2-weighted images.

A retrospective study of 97 patients undergoing 101 image-guided adrenal biopsies (IGABs) was performed to analyze the effects of specific pathologic results on test characteristics. Three categories of pathologic results (benign adrenal tissue, malignant tissue, and nondiagnostic) were compared with outcomes. Diagnostic samples were obtained in 86% of cases. Among 72 patients with proved outcomes, IGAB had an accuracy of 96%, a sensitivity of 93%, and a negative predictive value of 91% (92% in patients with bronchogenic carcinoma). In this subset of patients, 33 had biopsy specimens that contained benign adrenal tissue. In these 33 patients, three masses (each smaller than 3 cm) proved malignant. In the 14 patients with nondiagnostic samples, two masses proved malignant. Obtaining benign adrenal tissue was highly predictive of benignity, even in the setting of lung cancer. The authors conclude that IGAB is an accurate procedure in both oncologic and nononcologic patients. However, when the biopsy specimen does not contain benign adrenal tissue or malignant cells, repeat percutaneous biopsy or surgery should be considered.

The computed tomographic (CT) appearance of splenic infarction has classically been described as peripheral, wedge-shaped, and low in density. Two investigations were designed to determine the appearance of splenic infarcts: (a) a clinical study of 12 patients and (b) a canine experimental model. In the clinical study, two previously undescribed patterns of splenic infarction were found. The classic peripheral, wedge-shaped defects were seen in four patients; multiple, heterogeneous lesions were seen in five; and massive hypodense lesions were noted in three. In three of the nine patients who had both precontrast and postcontrast CT scans, the unenhanced images alone would not have permitted the diagnosis. Contrast enhancement markedly improved infarct visualization in the remaining six. The experimental study of splenic infarction in dogs indicated that CT images can accurately depict the various phases of an infarct as it evolves through stages of congestion, hemorrhage, inflammation, organization, and fibrosis. In addition, a new contrast material--liposome-encapsulated diatrizoate--was used in one of the dogs and was found to produce greater and more sustained differences between normal and abnormal tissue than did conventional contrast material.

A combined radiologist-computer system substantially improved accuracy of body MR radiologists in the diagnosis of prostate cancer. High levels of accuracy were also achieved by the system with prostate MR specialists.

No abstract