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The film digitizer plays an important transitory role as an analog-to-digital bridge for the implementation of PACS on screen-film mammography. The objective of this phantom study was to compare the observer performance of a digitized mammogram on liquid crystal displays (LCDs) with that of the original film mammogram, and to clarify which matrix size of LCDs is adequate for the interpretation of digitized mammography. The American College of Radiology mammographic accreditation phantom containing variously sized fibrils, simulated microcalcifications, and tumor-like masses was radiographed with a screen-film mammographic system. The original film was digitized with a sampling pitch of 50 mum and a density depth of 12 bit. Six observers who were trained in mammography individually viewed digitized images on LCDs and original film. Observer performance of a digitized mammogram with a 2-megapixel LCD was compared with that of original film. The observers were asked to rate the detectability of each test object according to a three-point scale (obviously visible=2, barely detectable=1, undetectable=0). The difference in the mean score between two systems at each object was evaluated by the Wilcoxon's test. In addition, the dependence of observer performance on the matrix size of LCDs ranging from 1-to 5-megapixel was tested with Scheffé's multiple comparison. The observers also judged the detectability according to the three-point scale. The results show that the digitized mammogram provides acceptable but slightly inferior detectability than original film. There was no dependence of matrix size in observer performance with more than 2-megapixel LCDs.

Three-dimensional data on the left ventricle at quasi-end-diastole and quasi-end-systole were acquired by helical scanning CT in 12 patients. Short axial images of the left ventricle and long axial images of the papillary muscle were created using multiplanar reconstruction. Left ventricular dimensions and the length of the papillary muscle were measured, and fractional shortening of the papillary muscle was calculated. There was a good correlation between left ventricular dimensions measured by echocardiogram and helical scanning CT (end-diastole: r = 0.94: end-systole: r = 0.86; fractional shortening of left ventricular dimension: r = 0.84). Papillary muscle fractional shortening was 6.3% in the ischemic group and 21.5% in the non-ischemic group (p < 0.005). Helical scanning CT is clinically useful for the assessment of left ventricular papillary muscle function.

Purpose: To assess the usefulness of fractal geometry in quantitatively evaluating the convergence of peripheral vessels on peripheral lung tumors in maximum intensity projection (MIP) images., Materials and Methods: We studied the MIP images of 34 pathologically proved small peripheral lung tumors (lung cancer in 21, hamartoma in 13) in 34 patients. To obtain MIP images, spiral CT (SOMATOM PLUS; Siemens) was performed during a single breath hold (24-second scan time, 2-mm section thickness, and 2 mm/sec table feed time, reconstructed at 1-mm increments). To evaluate the convergence of the peripheral vessels and bronchi towards the tumor, we fixed a region of interest (ROI) on the hilar side of the lung tumor, parallel to the chest wall, which consisted of 64 x 64 square pixels, in the images that divided at the center of the window width. We counted the overlapping pixels by the two-dimensional box-counting method and obtained fractal dimensional data on lung cancers and hamartomas., Results: There was a statistically significant difference in the fractal dimension (D) between lung cancers (D = 1.81 +/- 0.13) and hamartomas (D = 1.67 +/- 0.10) (P = 0.0067)., Conclusion: Fractal geometry could be useful in the diagnosis of small peripheral lung tumors.

A 56-year-old man was admitted to our hospital because of hemoptysis, and dyspnea. Breathing sounds decreased and rhonchi was audible in the right lung. Chest X-ray and Chest CT showed infiltrative shadows in the bilateral lower lobes. He was intubated and bronchofiberscopy revealed mucosal necrosis and hemorrhage of the lower trachea and the bilateral bronchi. MRSA was isolated from sputum and bronchial lavage fluids. He was diagnosed as NTB caused by MRSA. On the 7th day in hospital, he suffocated by the necrotic tissue and autopsy was performed. NTB is a very uncommon disease in adults, especially ones who are not under mechanical ventilation.

The high sensitivity of CT during arterial portography (CTAP) for hepatic lesions is accompanied with a lack of specificity for diagnosis. Combined CTAP and CT hepatic angiograpy (CTHA) had been proved to improves lesion detection and heightens confidence in interpreting perfusion abnormalities. We describe a new double lumen - coaxial catheter system for performing combined CTAP and CTHA without the need for repeated transfer of the patient or bilateral arterial punctures. This technique was employed in eight patients with liver neoplasms. In all eight patients, CTAP and CTA images were obtained successfully. We concluded that this method was useful for the evaluation of liver tumors.

A rare case of malignant peritoneal mesothelioma in a 49-year-old Japanese woman is presented. The tumor was limited to the peritoneum, and was cytologically and histologically identified as being composed of two components, epithelial and non-epithelial forms. The transition in her CA-125 level suggested that this tumor had good prospects of developing into a malignant mesothelioma. The good prognosis of the patient is considered to be attributed to detecting this tumor in its early stage and to aggressive chemotherapy.