PURPOSE: To describe the characteristic HRCT appearance and to evaluate the usefulness of HRCT in patients with welders' pneumoconiosis. MATERIALS AND METHODS: Chest radiographs and high-resolution computed tomography(HRCT) of 45 shipyard welders(male : female=41 : 4 ; age : 36-58 years, mean 47.8) with an occupational history of 4-25(mean 15.8) years were evaluated. Small rounded opacities in chest radiographs were read accordingto the ILO standard films(1980). HRCT were evaluated with micronodules, ground-glass attenuation, and other findings. Serial HRCT scans of seven welders taken 27 months apart were also evalauted. Two of these were still working in that job ; five had not worked as welders for 1-6(mean 4.4) years. RESULTS: HRCT of welders' pneumoconiosis showed poorly marginated centrilobular branching or dot opacities of low attenuation(n=36, 80.0%)with variable profusion and extent and ground-glass attenuation(n=8, 17.8%). HRCT abnormalities were seen in 39 welders(86.7%). It was able to depict micronodules(n=13) and/or ground-glass attenuation(n=3) in 15(68.2%) of 22welders with normal chest radiograph. Serial HRCT revealed no changes in parenchymal abnormalities(n=6) andslightly decreased profusion of micronodules(n=1). There was no HRCT abnormality suggesting gross parenchymal fibrosis. CONCLUSION: HRCT is more sensitive than chest radiography in detecting parenchymal changes in welders' pneumoconiosis, with characteristic poorly-marginated centrilobular branching opacities or dots and ground-glass attenuation. These HRCT appearances may be helpful in differentiating welders' pneumoconiosis from other diffuse lung diseases.
Pneumoconiosis* ; Radiography ; Radiography, Thoracic ; Thorax

No abstract available.
Radiography, Thoracic* ; Thorax*

No abstract available.
Pneumonectomy* ; Radiography, Thoracic* ; Thorax*

No abstract available.
Pneumonia* ; Radiography, Thoracic* ; Thorax*

Primary pulmonary amyloidosis is a rare disease, and is classified as either tracheobronchial or parenchymal ; the latter is also divided into nodular and diffuse alveolar septal forms. The alveolar form is extremely rare and usually produces reticular and nodular opacities. We describe a case of alveolar septal pulmonary amyloidosis manifested as multiple small nodules on chest radiograph and disseminated micronodules mainly in centrilobular and subpleural location without reticular opacities, on HRCT.
Amyloidosis* ; Radiography, Thoracic ; Rare Diseases

PURPOSE: The purpose of this study was twofold. In a preliminary study, we evaluated the accuracy of 3-D(three-dimensional) CT for the estimation of pneumothorax volume and for providing the optimal postprocessing method for clinical study. In the clinical study, we determined which of the two methods, Collins' and Axel's, was more accurate for the estimation of pneumothorax volume, as seen on chest radiographs, using 3-D CT as the standard of reference. MATERIALS AND METHODS: In the preliminary study, 3-D CT was applied to phantoms and to four patients with p-neumothorax using two different postprocessing methods, manual contour delineation and thresholding. In the clinical study, 3-D CT was performed in 13 patients with pneumothorax. For the purpose of evaluating conventional radiographs, a localizer scan was used for comparing the accuracy of Collins' method with that of Axel's method, with 3-D CT as the standard of reference. RESULTS: The preliminary study revealed that 3-D CT estimated pneumothorax volume with great accuracy and that manual contour delineation and thresholding measured volume equally well. Because of the shorter postprocessing time required with thresholding than with manual contour delineation (5 min versus 30 min), the former was used during clinical study. The results of this indicated close correlation between the measurements obtained using Collins' method on chest radiographs and those obtained by 3-D CT(r=0.95, p<0.05). In contrast, measurements obtained using Axel's method correlated poorly with those obtained by 3-D CT (r=0.55, p>0.05). CONCLUSION: 3-D CT can estimate pneumothorax volume with great accuracy. Collins' method is superior to Axel's method for the quantification of pneumothorax volume as seen on chest radiographs.
Humans ; Pneumothorax* ; Radiography, Thoracic* ; Thorax*

PURPOSE: To evaluate the diagnostic accuracy of chest x-ray interpretation of diffuse calcification of pulmonary nodules. MATERIALS AND METHODS: On plain chest radiograph and CT, 152 pulmonary nodules with diffuse calcification in 98 patients were selected. The nodules were of various diameters : 44 were of 0.5 - 1cm (Group1), 58 were of 1 - 2cm (Group 2), and 50 were of 2 - 3cm (Group 3). On plain chest radiograph, diffuse calcification was considered to be present when the density of pulmonary nodules of 0.5 - 1cm and 1 - 2cm indiameter was greater than that of the overlapping area of the second and fifth ribs. The density of nodules 2-3cmin diameter was compared with that of the mid-claviclar cortex; calcification was considered to be present when the density of the former was greater than that of the latter. Diffuse calcification of a pulmonary nodule on CT image was considered to be present when more than 10% of the area of the nodule showed a higher attenuation than the surrounding rib cortex. RESULTS: The overall diagnostic accuracy of chest radiographs in the detection of diffuse calcification was as follows : sensitivity 77.6%, specifity 89%, PPV (positive predictive value) 82.3%, NPV(negative predictive value) 86.9%. In group 1, sensivity was 96%, specifity 89.5%, PPV 91.6%, and NPV 94.9%. In group 2 nodules, sensitivity was 77.8%, specifity 91%, PPV 89%, and NPV 81.4%. In group 3, sensitivity was 56%,specifity 88% PPV 56% and NPV 83.9%. CONCLUSION: Chest radiographs showed relatively high accuracy in the diagnosis of diffuse calcificatio of pulmonary nodules, particulary when the nodule was less than 2cm in diameter. As the nodule increased in diameter, diagnostic accuracy declined.
Humans ; Radiography, Thoracic ; Ribs ; Thorax*

Pneumothorax, pneumomediastinum and pneumopericardium usually develop during emergency situations and these conditions may result in cardiopulmonary compromise, so an early and accurate diagnosis is seen as crucial for proper treatment. For diagnosis of pneumothorax, pneumomediastinum and pneumopericardium, chest radiography is a primary modality and CT can help for diagnosing them earlier and detecting associated abnormalities. The purpose of this pictorial essay is to describe the pathophysiology, various radiographic signs and diagnostic pitfalls of pneumothorax, pneumomediastinum and peumopericardium on chest radiographs that are correlated with CTs, and to aid the physician in the radiographic diagnosis.
Diagnosis ; Emergencies ; Mediastinal Emphysema* ; Pneumopericardium* ; Pneumothorax* ; Radiography ; Radiography, Thoracic ; Thorax

PURPOSE: Using dynamic range compression (DRC) processing, this study compared the detectability ofmediastinal lines by conventional film screen rediography (FS) and by storage phosphor digital radiography(DR). MATERIALS AND METHODS: We selected 200 normal consecutive chest radiographs (100 FS, 100 DR) ; dynamic rangecompression was applied to DR processing and moving grids were used in both systems. Seven mediastinal lines (leftfaraspinal, right paraspinal, azygoesophageal, left para-aortic, posterior junctional, anterior junctional andright paratracheal) were scored from 0 point to 3 point(0:not visible, 1:suspiciously visible, 2:visible, but notclear, 3: clearly visible) according to visibility and sharpness, as agreed by a radiologist and a resident. Thedifferences between the two modalities were compared and analyzed by chi-square test. RESULTS: Among the 1400mediastinal lines analyzed, 419 lines by DR(59.9%) and 232 lines by FS(33.1%) were scored more than 2 points. Inall mediastinal lines except the left para-aortic, DR was more detectable and clearer than FS, with statisticalsignificance(P<.01). CONCLUSION: DR processed with DRC visualizes mediastinal lines more frequently and clearlythan conventional FS, and is therefore thought to be useful for the evaluation of mediastinal diseases.
Mediastinal Diseases ; Radiographic Image Enhancement ; Radiography* ; Radiography, Thoracic

This paper illustrates the spectrum of CT findigns of pulmonary tuberculosis in children and shows the advantages and complementary nature of CT compared with conventional radiography. Common CT manifestations of pulmonary tuberculosis in children are mediastinal or hilar lymphadenopathy, air-space consolidation, atelectasis and disseminated nodules. CT is useful in the detection of the disease in equivocal chest radiographs, in the characterization of lesions, by demonstrating caseation necrotic areas, calcification and bronchogenic spread nodules, and in defining the extent of the disease and its complications. This in formation will be helpful in the diagnosis and evaluation of tuberculosis in children.
Child* ; Humans ; Lymphatic Diseases ; Radiography ; Radiography, Thoracic ; Tuberculosis ; Tuberculosis, Pulmonary*