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The advantages of imaging the chest with digital storage phosphor radiography (SR) may be nullified by its spatial resolution, which is lower than that of conventional film radiography (FR). To test the reader detection performance with the two modalities under clinical conditions, the authors compared 140-kVp isoexposure SR (system resolution: 0.2 mm, 10 bits) and FR images of a variety of chest abnormalities proved by computed tomography (CT) (157 patients, 244 abnormalities, 5,652 observations, six readers). In all tests, SR was as good as or better than FR (P less than .05). In overall detection, indicated by the average area of receiver operating characteristics, SR and FR were equivalent. SR was superior for mediastinal lesions and for pulmonary opacities greater than 2 cm in diameter. For all other types of pulmonary lesions and pleural abnormalities, SR and FR were equivalent. Currently available commercial SR systems can replace film radiographic systems in the detection of a wide variety of chest lesions. SR is likely to enable better visualization than FR in the detection of mediastinal and large pulmonary abnormalities.

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A prospective study was undertaken to evaluate the significance of asymmetric breast tissue (asymmetric volume of breast tissue, asymmetrically dense breast tissue with preserved architecture, or asymmetrically prominent ducts) on mammograms. Of 8,408 mammograms obtained in 1985, 221 (3%) demonstrated asymmetric breast tissue. Follow-up was 36-42 months after the initial mammographic study. During this time none of the patients underwent biopsy on the basis of mammographic findings, although 20 underwent excisional biopsy because of clinical findings. Breast cancer was diagnosed in two patients and breast lymphoma in one patient. Biopsy specimens from the remaining 17 patients were benign. At mammography, all three malignant lesions had a palpable abnormality associated with the asymmetric tissue. Breast cancer was not found in any of the remaining 201 patients. Therefore, an asymmetric volume of breast tissue, asymmetrically dense breast tissue, or asymmetrically prominent ducts that do not form a mass, do not contain microcalcifications, or do not produce architectural distortion should be viewed with concern only when associated with a palpable asymmetry and are otherwise normal variations.

Following the observation of several cases of localized echogenic foci in abdominal parenchymal organs in patients with acute bleeding due to trauma, an experimental study was designed to define the sonographic appearance of fresh, nonhemolyzed blood. Ultrasound scanning performed before and after the injection of blood or air into the parenchyma of cadaveric organs (liver, spleen, and kidney) resulted in consistent ultrasonic patterns. Linear echogenic foci resulted from the injection of 0.5 to 2.0 ml of blood, rounded echogenic foci were seen with air or 3- to 10-ml injections of blood, and the injection of contrast material (into the liver only) caused poorly defined hypoechoic areas. To determine if the ultrasound appearance of the cadaveric organs could have been caused mainly by air, an in vivo experiment was performed in which computed tomograms of the liver of a dog that had been injected with autologous blood were obtained. It is concluded that CT confirmed the ultrasound findings, and that ultrasound is useful for the investigation of hematoma following blunt, and possibly penetrating, trauma.