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INTRODUCTION: Hard metal pneumoconiosis is a rare but serious disease of the lungs associated with inhalational exposure to tungsten or cobalt dust. Little is known about the radiologic and pathologic characteristics of this disease and the efficacy of treating with immunosuppression. OBJECTIVE: We describe the largest cohort of patients with hard metal pneumoconiosis in the literature, including radiographic and pathologic patterns as well as treatment options. METHODS: We retrospectively identified patients from the University of Pittsburgh pathology registry between the years of 1985 and 2016. Experts in chest radiology and pulmonary pathology reviewed the cases for radiologic and pathologic patterns. RESULTS: We identified 23 patients with a pathologic pattern of hard metal pneumoconiosis. The most common radiographic findings were ground glass opacities (93%) and small nodules (64%). Of 20 surgical biopsies, 17 (85%) showed features of giant cell interstitial pneumonia. Most patients received systemic corticosteroids and/or steroid-sparing immunosuppression. CONCLUSIONS: Hard metal pneumoconiosis is characterized predominately by radiographic ground glass opacities and giant cell interstitial pneumonia on histopathology. Systemic corticosteroids and steroid-sparing immunosuppression are common treatment options.

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BACKGROUND: Tube thoracostomy remains the standard of care for the treatment of pneumothoraces and simple effusions. This report describes a favorable experience with the 8.3 French pigtail catheter as a less invasive alternative to traditional chest tube insertion. METHODS: We retrospectively reviewed 109 consecutive pigtail catheter placements. Catheters were inserted under local anesthesia at the bedside without radiographic guidance. Pre- and post-insertion chest radiographs were reviewed to determine efficacy of drainage. RESULTS: Fifty-one of 109 patients (47%) were mechanically ventilated and 26 patients (24%) had a coagulopathy. There were no complications related to pigtail catheter insertion. Seventy-seven pigtail catheters were placed for pleural effusion and 32 for pneumothorax. Mean effusion volume decreased from 43 to 9 percent, and drainage averaged 2899 ml over 97 hours. Mean pneumothorax size diminished from 38 to 1 percent during an average 71-hour placement. Clinical success rates in the effusion and pneumothorax groups were 86 and 81 percent, respectively. CONCLUSION: The pigtail catheter offers reliable treatment of pneumothoraces and simple effusions and is a safe and less invasive alternative to tube thoracostomy.

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RATIONALE AND OBJECTIVES: To assess the usefulness of classifying degree of difficulty in abnormality detection and to determine the effect of knowing the true diagnosis when selecting subtle images for observer-performance studies. MATERIALS AND METHODS: A total of 529 posteroanterior chest images that had been used in a multiabnormality, multireader observer-performance study were rated by three observers as to the difficulty of determining the presence or absence of each abnormality when the true diagnosis was known and when it was not known. Changes in image subtlety ratings were evaluated, and actual observer-performance results for the different groups of images grouped according to raters' classifications with and without availability of the true diagnosis were compared. RESULTS: The majority of negative cases (9,168 of 12,258, 74.8%) were rated as "easy" to determine. Substantial changes were made during the selection of the "subtle" case category when the truth was known compared with when the truth was not provided. These changes caused differences between typical and subtle cases in terms of observer performance. Combined ratings of case subtlety by agreement of multiple classifiers resulted in a well-ordered selection with decreasing observer performance as a function of subtlety ratings. CONCLUSION: Cases for observer-performance studies that stress the diagnostic system can be successfully selected in the multiple-disease setting by experienced readers and should be selected with the truth known to the raters. The degree of agreement by multiple raters can be used to refine subtlety ratings.

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This study compared a five-category ordinal scale and a two-alternative forced-choice subjective rating of image quality preferences in a multiabnormality environment. 140 pairs of laser-printed posteroanterior (PA) chest images were evaluated twice by three radiologists who were asked to select during a side-by-side review which image in each pair was the "better" one for the determination of the presence or absence of specific abnormalities. Each pair included one image (the digitized film at 100 microns pixel resolution and laser printed onto film) and a highly compressed (approximately 60:1) and decompressed version of the digitized film that was laser printed onto film. Ratings were performed once with a five-category ordinal scale and once with a two-alternative forced-choice scale. The selection process was significantly affected by the rating scale used. The "comparable" or "equivalent for diagnosis "category was used in 88.5% of the ratings with the ordinal scale. When using the two-alternative forced-choice approach, noncompressed images were selected 66.8% of the time as being the "better" images. This resulted in a significantly lower ability to detect small differences in perceived image quality between the noncompressed and compressed images when the ordinal rating scale is used. Observer behavior can be affected by the type of question asked and the rating scale used. Observers are highly sensitive to small differences in image presentation during a side-by-side review.

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BACKGROUND: Previous studies have reported conflicting results on whether pulmonary radiographic findings predict mortality for patients with community-acquired pneumonia (CAP). OBJECTIVE: To determine whether pulmonary radiographic findings at presentation are independently associated with 30-day mortality in patients with suspected CAP. METHODS: This study was conducted as part of the Pneumonia Patient Outcomes Research Team multicenter, prospective cohort study of ambulatory and hospitalized patients with clinical and radiographic evidence of CAP. For each patient with CAP, a structured data form was completed by a panel of radiologists to evaluate the radiographic pattern of infiltrate, number of lobes involved, presence of pleural effusion, and 8 other radiographic characteristics. Cox proportional hazards models were used to evaluate the independent association between radiographic findings and 30-day mortality, while controlling for patient demographic, clinical, and laboratory characteristics with a known association with this outcome. RESULTS: Of 2287 patients enrolled in the Pneumonia Patient Outcomes Research Team cohort study, 1906 patients (83.3%) had a pulmonary radiographic infiltrate confirmed by the radiology panel. Overall, 30-day mortality in this cohort was 4.9%. Univariate regression analyses demonstrated the following radiographic characteristics to be significantly associated with 30-day mortality: (1) bilateral pleural effusions (risk ratio [RR], 7.0; 95% confidence interval [CI], 3.9-12.6); (2) a pleural effusion of moderate or greater size (RR, 3.4; 95% CI, 1.4-8.4); (3) 2 or more lobes involved with infiltrate (RR, 2.5; 95% CI, 1.6-3.8); (4) bilateral infiltrate (RR, 2.8; 95% CI, 1.9-4.2); (5) bronchopneumonia (RR, 1.6; 95% CI, 1.0-2.7); and (6) air bronchograms (RR, 0.5; 95% CI, 0.2-0.9). Multivariate analysis of radiographic features and other clinical characteristics showed the presence of bilateral pleural effusions (RR, 2.8; 95% CI, 1.4-5.8) was independently associated with mortality. CONCLUSIONS: In patients with CAP, the presence of bilateral pleural effusions is an independent predictor of short-term mortality. This finding, which is available at presentation, can help guide physicians' assessment of prognosis in CAP.

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OBJECTIVE: To evaluate the interobserver reliability of pulmonary radiographic findings in patients with community-acquired pneumonia (CAP). DESIGN: A prospective, multicenter study. SETTING: Physician offices, medical walk-in clinics, emergency departments, and inpatient wards affiliated with three university hospitals, one community hospital, and one staff model health maintenance organization in three geographic areas. METHODS: Copies of the initial chest radiograph of patients suspected of having CAP were independently read by two staff radiologists at the coordinating university hospital. Interobserver reliability for the interpretation for radiographic findings was assessed by calculation of agreement rates and the kappa statistic. PARTICIPANTS: Adults (age > or = 18 years) with symptoms or signs of CAP and a pulmonary radiographic infiltrate documented by a local study site radiologist. RESULTS: Among the 282 patients whose initial pulmonary radiographs were evaluated, there was agreement between the two staff radiologists on the presence of infiltrate in 79.4% and on the absence of an infiltrate in 6.0% (kappa = 0.37; 95% confidence interval [CI] = 0.22 to 0.52). For the 224 patients with an infiltrate identified by both radiologists, there was further agreement that the infiltrate was unilobar in 41.5% and multilobar in 33.9% (kappa = 0.51; 95% CI = 0.28 to 0.62), pleural effusion was present in 10.7% and absent in 73.2% (kappa = 0.46; 95% CI = 0.33 to 0.50), and the infiltrate was alveolar in 96.3% of patients and interstitial in no patients (kappa = -0.01; 95% CI = -0.03 to 0.00). Among the 210 patients with an alveolar infiltrate, both radiologists classified the infiltrate as lobar in 74.6% and bronchopneumonia in 2.4% (kappa = 0.09; 95% CI = -0.04 to 0.22), and agreed on the presence of air bronchograms in 7.6% and their absence in 52.9% (kappa = 0.01; 95% CI = -0.13 to 0.15). CONCLUSION: In patients with CAP, two university radiologists identified the presence of infiltrate, multilobar disease, and pleural effusion with fair to good interobserver reliability. However, interobserver reliability for the pattern of infiltrate and the presence of air bronchograms was poor.

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Forced-choice just noticeable difference (JND) studies are extremely sensitive to image quality variations that are below the threshold at which the differences are apparent to or definable by the observer. Paired comparisons of 4K and 2K laser-printed posteroanterior chest images consistently demonstrated that although images are viewed as comparable by radiologists, when forced to choose the better ("sharper") image, they actually select the higher-resolution images in 83% of the paired observations. We conclude that small differences in image quality may be detectable even in image sets which are considered to be comparable by subjective assessments.

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OBJECTIVE: The purpose of this study was to compare observer performance in interpreting high-quality, digitally acquired computed radiographs of the chest displayed on either laser-printed radiographs or a workstation with observer performance in interpreting conventional chest radiographs. SUBJECTS AND METHODS: We performed a receiver-operating-characteristic study in which the presence or absence of five abnormalities was determined by nine experienced radiologists on 310 posteroanterior radiographs of the chest displayed in three forms: conventional radiographs, laser-printed films of digital radiographs, and digital radiographs on a high-resolution workstation. RESULTS: The results of our study suggest that observer performance with laser-printed films of digital radiographs obtained with high-resolution (4K x 5K), high-contrast sensitivity (12 bits) and appropriate exposure is comparable to observer performance with conventional radiographs. Observer performance with digital radiographs displayed on the workstation was found to be significantly lower for abnormalities that contained high-frequency and low-contrast information (e.g., interstitial disease and pneumothorax). CONCLUSION: Computed radiography technology can produce image quality that is adequate for interpreting posteroanterior radiographs of the chest. Observer performance is not as good when radiographs displayed on workstations are used to diagnose specific abnormalities.

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The records of 100 lung transplant recipients (13 heart-lungs, 45 double-lungs, and 42 single-lungs) from September 1990 through April 1992 were reviewed to determine the role of cardiopulmonary bypass (CPB) in early graft dysfunction. Fifty-five patients requiring CPB (CPB group) for 186 +/- 54 minutes were compared with the 45 patients without CPB (no-CPB group). All of the heart-lung and en-bloc double-lung transplantations were performed under CPB, with pulmonary vascular lung disease the principal diagnosis, resulting in a significantly younger age population in the CPB group. All other donor- and recipient-related factors matched well in both groups. Of 38 bilateral single-lung transplantations, CPB was used in 18. In double-lung and heart-lung recipients gas exchange of the allografts was evaluated by the arterial/alveolar oxygen tension ratios at nine intervals during the first 72 hours. The mean arterial/alveolar oxygen tension ratio in the CPB group was 0.48 +/- 0.19, significantly lower than in the no-CPB group with 0.60 +/- 0.22 (p = 0.025). All patients had radiographic interpretation and scoring of pulmonary infiltrates from chest roentgenograms taken within 12 hours after reperfusion. The CPB group had more severe pulmonary infiltrates than the no-CPB group (p = 0.034). Prolonged intubation defined as 7 days or longer occurred significantly more often (29/55) in the CPB group than in the no-CPB group (8/45) (p = 0.003). Actuarial graft and patient survival at 1 month was better in the no-CPB group than in the CPB group (42/45 versus 44/55 [p = 0.05] and 43/45 versus 45/55 [p = 0.033], respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

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The applications for which picture archiving and communication systems (PACS) will be used must dictate the technological requirements. Technology-driven integrated PACS have been implemented and tested in a variety of clinical environments. PACS do not generate new revenues, albeit they may affect the bottom line of health care delivery systems through increased efficiency of radiology and, perhaps more important, of the other physicians who use radiologic services. User performance expectations require that trade-offs are evaluated and compromises are made when PACS are designed using currently available technology. In this report, functional requirements for clinical PACS are discussed. These include reliability, speed, ease of use, connectivity, and upgradability. The advantages and disadvantages of specific choices are presented from a utility perspective of an end user.

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Posttransplant lymphoproliferative disorder (PTLD) is a serious complication of organ transplantation and immunosuppression. Early diagnosis and treatment greatly affect prognosis. Chest radiographs (n = 13), chest computed tomographic (CT) scans (n = 2), or both (n = 20) from 35 patients with intrathoracic PTLD were retrospectively studied to define the intrathoracic manifestations of this disorder. Intrathoracic abnormalities consisted of pulmonary nodules (16 patients), patchy air-space consolidation (three patients), mediastinal and hilar adenopathy (17 patients), thymic enlargement (two patients), pericardial thickening and/or effusions (two patients), and pleural effusions (four patients). Multiple, well-circumscribed pulmonary nodules with or without mediastinal adenopathy are highly suggestive of PTLD. However, pathologic examination is usually necessary for a definitive diagnosis.

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ROC methodology has been expanded in recent years to include multi-disease experiments. To accommodate these changes, different rating formats, general or disease specific, can be used. No experimental data are available concerning the possible effects of the rating format on the results of these studies. We performed a multi-observer, multi-disease study in which 196 chest images were rated using a format where each disease was evaluated individually and one in which the cases were evaluated without scoring a specific disease. The results indicate that for our data set, the overall assessment of accuracy was not significantly affected by the study format used. Thus, in spite of the difficulties in selecting appropriate controls and the necessity of reassessing sample size considerations, the disease-specific format appears to produce an assessment of accuracy equivalent to that produced by the general format. This equivalence permits the use of the disease-specific approach since it more closely simulates the readers' true environment and is more appropriate for comparing imaging systems that may have a relative accuracy that is disease specific.

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This article describes the current status and potential applications of high-resolution storage phosphor for imaging of the chest. Digital imaging that uses storage phosphor technology is easily adaptable to existing x-ray--generating equipment and can also be used with mobile equipment. The wide latitude of the storage phosphor technique permits satisfactory imaging in situations in which exposure factors cannot be accurately estimated or easily controlled. Early experience with an experimental Kodak high-resolution (4K x 4K) storage phosphor system suggests that standard and portal chest images of excellent quality can be obtained. Many issues must be resolved, however, before digital radiology with a storage phosphor can be advocated as being preferable to conventional film-screen systems. These issues, which include display modalities (film or television monitor), resolution requirements, and the effects of image processing, can only be resolved by further large-scale accuracy studies. The change to a digital imaging system will involve major expenditures for equipment and computers. Cost will be related largely to the level of spatial resolution required for primary radiographic diagnosis.

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Portal verification images were generated by the photon contamination in electron beams produced by a linear accelerator during treatment of patients receiving high-energy electron radiation therapy. Both conventional and storage phosphor methods yielded projection radiographs in which anatomy of the irradiated and surrounding tissue was demonstrated. Exposed phantoms were used to confirm that the images represent a true projection of the radiation field. A preliminary series of 22 cases was evaluated by two radiotherapists and judged subjectively to be of clinical value. Geometric error, or more importantly, the lack thereof, during high-energy electron treatments was easily confirmed with this method. In three cases, the treatment protocol was corrected based on the images obtained. Because the readout process of storage phosphor images allows for gain adjustments and post-processing, the images obtained with this method were found to delineate anatomy in the treated and surrounding tissues somewhat more consistently than could conventional images.

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Patients who survive the postoperative period after combined heart-lung transplantation are at risk for developing progressive airway damage consisting of central bronchiectasis and bronchiolitis obliterans. The cause of these abnormalities is uncertain, but they are thought to represent a form of chronic rejection. The chest radiographs and medical records of 11 transplantation patients with proved bronchiolitis obliterans were reviewed retrospectively. A pathologic diagnosis was made by open-lung biopsy (five patients), transbronchial biopsy (three patients), and autopsy (two patients). Clinical criteria alone were used for diagnosis in one patient. In all patients, the chest radiographs showed parenchymal abnormalities consisting of linear-nodular, nodular, confluent nodular, or diffuse alveolar opacities. Radiographic evidence of central bronchiectasis was present in nine of the 11 patients. This feature was not present on chest radiographs of five randomly selected asymptomatic transplant patients. We conclude that the parenchymal lung changes in bronchiolitis obliterans in transplant patients are nonspecific and are radiographically indistinguishable from other infectious and noninfectious complications. The presence of central bronchiectasis (nine of the 11 patients) may be a distinctive radiographic finding in this group of patients.

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Two drawbacks in quality of portal radiographs in radiation therapy are their low contrast and low spatial resolution. These are due to the low differential absorption of body tissues at therapeutic energies and to a relatively large radiation source. We used an experimental, high-contrast sensitivity storage phosphor imaging system (Eastman Kodak Co.) to produce portal images. The system consists of a storage phosphor detector, a high-contrast sensitivity laser scanner (12 bit), an image processing module, and a laser printer (12 bit). Patients undergoing radiation therapy treatments had both a conventional portal image and a storage phosphor image taken. Both were displayed side-by-side and were evaluated independently by three radiotherapists according to quality of information to verify the treatment field. Each of the three radiotherapists rated the storage phosphor images to be better (p less than 0.001) than the conventional images. However, rated improvements of low-contrast storage phosphor images of the pelvis and abdomen (40) were significantly lower than those of high-contrast (head, neck, and chest) images (53).

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In a retrospective study of proved pseudoaneurysms (PAs) in 15 patients with transplanted organs (11 liver, three kidney, one pancreas), the results of computed tomography (CT), duplex sonography, and angiography were reviewed. Of the 15 cases of PA, eight occurred at the arterial anastomosis and seven were nonanastomotic. Three of the eight anastomotic PAs were caused by infection. Of the seven nonanastomotic PAs, four were caused by percutaneous biopsy, two were caused by infection, and one was of undetermined cause. In nine (60%) of the 15 patients the PAs were incidentally detected at imaging studies performed for other reasons. Diagnosis requires a high degree of suspicion. CT was performed in nine cases and duplex sonography in ten. The diagnosis of PA was made with CT in six (67%) patients and with duplex sonography in five (50%). CT and duplex sonography could not enable diagnosis when the PA was small, when the arterial anastomosis was not included in the field of study, or when enhancement with intravenously administered contract material was suboptimal. Angiography depicted the PAs in all 15 patients. In three liver transplant recipients with gastrointestinal tract bleeding, the causative PAs were detected only with angiography.

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We compared storage phosphor images with high-quality conventional film-screen images by evaluating physicians' perceptions of image quality and their levels of confidence in making diagnostic interpretations. Eight physicians each examined 11 posteroanterior storage phosphor chest images (obtained with an experimental high-resolution storage phosphor system) side by side with conventional film images of the same patients. The storage phosphor images were obtained only minutes after the conventional radiographs were obtained. Storage phosphor images were digitally printed onto films in two different formats: a full-size (12 X 14 in. [30.5 X 35.6 cm]) and a half-size format of four computer-processed, minified images (6 X 7 in. [15.2 X 17.8 cm] each). Most of the responses rated the quality and resolution/sharpness of conventional images, as well as their ability to display the complete lung field, as either "excellent" or "good"; however, the storage phosphor images received significantly better ratings (p less than .05). Computer-processed minified versions of the storage phosphor images also received better ratings than did the conventional images. When the physicians were asked to rate their confidence level in making diagnoses with each of the two techniques, in 74 of 88 cases they indicated that their level of confidence would be at least as high when using the storage phosphor images as when using the conventional images.

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A case of thoracic extramedullary hematopoiesis with a large fatty component presented a unique CT appearance that has not been previously reported.

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