Chest radiographic image quality: comparison of asymmetric screen-film, digital storage phosphor, and digital selenium drum systems--preliminary study.

Conventional screen-film radiography does not display all regions of the thorax satisfactorily. Three chest radiographic techniques display both the lung and the mediastinum with good contrast. These techniques are asymmetric screen-film (ASF), digital storage phosphor (DSP), and digital selenium drum (DSD) imaging. ASF systems use two asymmetric screen-film combinations to produce a wide-latitude image of the thorax with good contrast in the lungs. In DSP systems, image data are acquired digitally with a wide dynamic range by using the optical output of a photostimulable phosphor plate; in DSD systems, the wide-range digital image data are acquired by using the electronic charge generated on a drum coated with a thin layer of amorphous selenium. The appearance of a DSP or DSD radiograph is then determined by user-selected image processing operations: tone scaling, spatial frequency processing, and dynamic range compensation. Digital chest radiographs processed with strong regional equalization provide both excellent contrast in the lungs and effective display of the mediastinum and chest wall. At visual comparison, the high lung contrast and good mediastinal, retrocardiac, and subdiaphragmatic detail provided by the DSD method distinguish it from the other two methods.

Rib enlargement in patients with chronic pleural disease.

OBJECTIVE: The purpose of this study was to assess the width of ribs in patients with chronic pleural disease. MATERIALS AND METHODS: On posteroanterior radiographs, we measured the horizontal width of ribs in the midaxillary line of four groups of patients: 41 selected patients with widened ribs and chronic pleural disease (group I), 30 consecutive patients with the clinical diagnosis of tuberculosis for 5 or more years who had radiographs that showed unilateral pulmonary or pleural disease (group II), 25 consecutive patients with the clinical diagnosis of empyema who had radiographs that showed unilateral pleural and often pulmonary parenchymal disease (group III), and 60 consecutive persons who received routine preemployment examinations that revealed no pulmonary or pleural disease (control subjects). Available clinical data were reviewed. RESULTS: We found a significant difference between the size of the ribs on the side of disease and the nondiseased side for groups I and II (p = .0008 and p = .045, respectively). We found no such difference for group III or the control group. The mean absolute values of the different widths of ribs on the side of disease and the nondiseased side were greater for groups I, II, and III than the absolute values of the different widths for the right and left ribs of the control subjects (p < .05). We identified tuberculosis, nontubercular empyema, thoracic surgery, blunt trauma, and metastatic tumor as causative agents in 24 (59%) of the 41 patients in group I. CONCLUSION: Rib enlargement is occasionally displayed radiographically in cases of chronic pleural disease and is confirmed by comparison of the two sides. In our selected patients (group I) with rib enlargement, tuberculosis was the most common cause of pleural disease, but nontubercular empyema, thoracic surgery, blunt trauma, and metastatic tumor were also found. Conversely, we found no rib enlargement in association with pleural disease of short duration. We have shown that rib enlargement can indicate the chronicity of pleural disease.

Can computed tomography of the chest stage lung cancer? Yes and no.

To determine the accuracy of computed tomography (CT) of the chest in the staging of lung cancer, we studied 418 patients with primary pulmonary carcinoma between 1979 and 1986. Each had a preoperative scan performed before detailed operative staging. Each CT scan was analyzed for components of the current TNM staging system. Computed tomography sensitivity and specificity for mediastinal lymph node metastasis were 84.4% and 84.1%, with corresponding positive and negative predictive accuracies of 68.7% and 92.9%, respectively. When TNM stages were derived from CT scans, only 190 of 418 (45.4%) completely agreed with operative staging. An additional 53 of 418 (12.7%) predicted the correct stage, although components of the TNM system were incorrect. In 94 of 418 scans (22.5%) CT overestimated the stage, whereas in 81 (19.4%) CT downgraded the stage. Computed tomography suggested metastatic lesions in liver, lung, adrenal gland, bone, or abdominal lymph nodes in 40 of 373 scans (10.7%); only five of 40 (12.5%) had documented metastasis. In summary, CT of the chest cannot accurately stage primary lung carcinoma according to the TNM classification. Because the negative predictive accuracy for mediastinal lymph node metastasis remains high (92.9%), invasive staging can be deferred for definitive thoracotomy when no lymphadenopathy is evident on CT. The high negative predictive accuracy for scans of the chest and upper abdomen makes CT a useful tool for exclusion of metastatic disease.

Computed tomographic evaluation of intrathoracic thyroid malignancy.

As only a few cases of intrathoracic thyroid malignancy with computed tomographic (CT) examination have been described, we reviewed the CT examinations of three patients with primary and five patients with recurrent thyroid malignancy involving the thorax. Irregular border of the thyroid mass, extension of tumor mass into mediastinal fat or chest wall, or lymphadenopathy suggested the malignant nature of the primary tumor. CT examination in recurrent disease demonstrated mediastinal, hilar and retrocrural adenopathy, compression of major vessels with collateral flow, pulmonary and bony metastases. CT was of value both in identifying the extent of disease and documenting response to treatment.

Chest pain and dyspnea related to "crack" cocaine smoking: value of chest radiography.

The chest radiographs of 71 patients who had chest pain or shortness of breath following the smoking of highly potent "crack" cocaine were retrospectively evaluated. Nine patients had abnormal findings on radiographs as follows: atelectasis or localized parenchymal opacification in four, pneumomediastinum in two, pneumothorax in one, hemopneumothorax in one, and pulmonary edema in one. Radiographic detection of these abnormalities was important in the clinical management of these patients. This spectrum of findings is presented with a discussion of the pathophysiologic mechanisms responsible.

Small-cell bronchogenic carcinoma: CT evaluation.

CT examinations in 37 patients with proved small-cell bronchogenic carcinoma studied before treatment were reviewed. The distribution of lymphadenopathy in the mediastinal compartments designated by the American Thoracic Society was assessed. The frequency of lymph node enlargement was right hilum (43%), left hilum (49%), one or both hila (84%), right upper paratracheal (32%), right lower paratracheal (54%), right tracheobronchial (65%), left upper paratracheal (14%), left lower paratracheal (38%), left peribronchial (35%), paraesophageal (14%), anterior mediastinum (24%), and subcarinal (65%). We also assessed the frequency of additional findings including pleural effusion (38%), pericardial thickening (38%), displacement or narrowing of either the tracheobronchial tree (68%) or major vessels (68%), and hepatic masses (24%). Mediastinal involvement was present in 92% of cases, as compared with 13% reported in a large series based on conventional radiography. These data show the spectrum of intrathoracic CT findings in proved, untreated cases of small-cell bronchogenic carcinoma.

Chest-wall invasion by carcinoma of the lung: detection by MR imaging.

Nineteen patients with bronchogenic carcinoma were studied by MR imaging to determine the presence of chest-wall invasion. All studies were carried out at 1.5 T, and the results were correlated with chest radiographs or CT scans. All MR studies were interpreted before surgery (13 cases) and without knowledge of the results of other radiologic studies. MR findings indicative of chest-wall invasion included a high-signal focus within the chest wall and/or chest-wall thickening with increased signal on spin-echo (SE) images having a repetition time of 2500 msec and an echo time of 50-100 msec (SE 2500/50-100). In one case, noncontour-deforming high-signal intensity within chest-wall musculature (but no other abnormality) was demonstrated on SE 2500/50-100 images. Coronal or sagittal imaging facilitated identification of tumor contiguity with extrathoracic structures in apical lesions. Contrast differences between normal and invaded chest wall on T2-weighted images were the most helpful in assessing chest-wall involvement. These preliminary observations indicate that MR imaging is useful in the evaluation of chest-wall invasion by carcinoma of the lung.

Limitations of CT in evaluation of neoplasms involving chest wall.

We reviewed the CT of 20 patients with peripheral lung malignancies in which CT appearance suggested chest wall invasion on the basis of extension of mass around ribs into fat or muscle of the chest wall, or definite bone destruction. We correlated these findings with other radiographic studies and surgical and autopsy results. All 11 cases in which CT indicated chest wall involvement on the basis of definite bone destruction were confirmed. Tumor extension into the chest wall was disproven in six of the remaining nine cases in which invasion was suggested on the basis of tumor infiltration between ribs or extension of tumor into fat or soft tissue planes. Our findings confirm the lack of reliability of CT findings in determining the extension of malignancy into the chest wall, except when definite bone destruction is present.

Thoracic manifestations of AIDS.

Of 67 hospitalized AIDS patients, 39 had pulmonary pathology. More than half of these patients died of pulmonary disease. Pneumocystis carinii, cytomegalovirus, Cryptococcus neoformans and Mycobacterium avium-intracellulare were the most common pulmonary pathogens, and Kaposi's sarcoma was the most common neoplasm. Infections and neoplasms frequently coexist in the thorax of an AIDS patient. The chest radiograph may be normal in an AIDS patient with active Pneumocystis pneumonia.

T1N0M0 bronchogenic carcinoma: assessment by CT.

We reviewed medical records and conventional chest radiographs that showed a solitary T1N0M0 nodule in 23 patients who had non-oat-cell bronchogenic carcinoma. No patient had evidence of metastases, either on the chest radiograph or clinically. All patients underwent computed tomography (CT) examination of the thorax, including the adrenal glands. Only one patient (4%) had mediastinal lymph nodes greater than 1 cm in diameter accessible to mediastinotomy; anterior mediastinotomy confirmed metastatic spread in this patient, which precluded curative resection. Three patients each had a mildly enlarged (2 cm or less) adrenal gland; however, follow-up study suggested that metastasis was not the cause of adrenal enlargement in these patients. This study reinforces concern over whether CT is warranted in the preoperative assessment of T1N0M0 bronchogenic carcinoma.