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C A Staples

Publications and source records attributed to C A Staples.

15 recordsLinked to original sources
PubMed1992

Computed tomography in the evaluation of benign asbestos-related disorders.

High-resolution CT is more sensitive than chest radiography and conventional CT in the detection and assessment of benign asbestos-related pleural and parenchymal diseases. The HRCT features of asbestosis correlate with clinical and functional restriction. The specificity of HRCT findings of asbestosis needs further evaluation. Given its low cost and availability, chest radiography remains the mainstay of imaging in benign asbestos-related diseases. CT (conventional or high-resolution) is not recommended as a universal screening test in asbestos-exposed workers. It has a useful role in identifying and quantitating pulmonary fibrosis distinct from emphysema and pleural disease, in distinguishing pleural disease from normal extrapleural soft tissues, and in clarifying the confusing chest radiograph or conflicting pulmonary function data. CT is useful in excluding a mass that may be obscured by extensive pleural and parenchymal fibrosis and is helpful in the follow-up of benign fibrotic masses or in the direction of their biopsy.

Asbestosis↗
PubMed1991

Chronic diffuse infiltrative lung disease: comparison of diagnostic accuracy of high-resolution and conventional CT.

We compared the accuracies of high-resolution CT (HRCT) and conventional CT in determining the specific diagnoses in 75 consecutive patients with chronic diffuse infiltrative lung disease. Without knowledge of clinical or pathologic data, two reviewers independently assessed three separate sets of CT scans in random order: three HRCT scans, three 10-mm collimation CT scans obtained at the same levels as the HRCT scans, and a complete conventional CT scan. The HRCT scans were obtained at the level of the aortic arch, tracheal carina, and 1 cm above the right hemidiaphragm by using 1.5-mm collimation and a high spatial resolution algorithm. Observers gave the most likely diagnosis along with their degree of diagnostic confidence. The correct diagnosis, irrespective of confidence level, was reached with 71% of the HRCT scans and with 72% of both the corresponding 10-mm and complete conventional CT scans. Confidence level 1 (definite) was reached with 49% of HRCT scans, 31% of corresponding 10-mm scans, and 43% of complete conventional CT examinations; the correct diagnosis was made in 92%, 96%, and 94% of those examinations, respectively. In none of the patients were findings on the limited HRCT scan normal when findings on the conventional CT scan were abnormal. We conclude that in most patients with chronic infiltrative lung disease a specific diagnosis can be made by obtaining a limited number of HRCT scans.

Adult↗
PubMed1991

Pulmonary angiitis and granulomatosis.

The presentation of a patient with multiple pulmonary nodules with or without cavitation and often with signs of a multisystemic vasculitis should suggest one of the pulmonary angiitis and granulomatosis syndromes. The five conditions traditionally considered together in the category of pulmonary angiitis and granulomatosis differ widely in their cause and pathogenesis and are more appropriately considered as variants or relatives of other processes. The radiologic features of this group of diseases, however, are similar, and it is useful to still consider them together. Table 1 summarizes the radiologic features of these conditions.

Bronchial Diseases↗
PubMed1990

Changes in total lung capacity during acute spontaneous asthma.

An increased TLC has been reported during exacerbations of asthma, but the methods used (helium, dilution, plethysmography) have been subsequently found unreliable in the assessment of lung volumes in patients with obstructive lung disease. To address this problem, we measured TLC (TLC-XR) from posteroanterior and lateral chest roentgenograms obtained during exacerbations (E) of asthma and after recovery (R) using planimetry in 12 asthmatic subjects. At recovery, TLC was also measured by plethysmography or by helium dilution for comparison with the radiographic measurement. The plethysmographic measurements were made with a panting frequency less than 1 Hz to allow for airway obstruction. A chest radiologist also used independent radiologic measurements of hyperinflation (lung height, diaphragmatic arc height, rib counts) to assess lung volumes. Mean FEV1 during E was 1.43 +/- 0.38 L, and significant improvement occurred at R (FEV1 = 2.81 +/- 0.58 L, p less than 0.05). Of the independent radiologic variables measured, only an increase in lung height distinguished the two sets of radiographs. Mean TLC-XR (E) (6.01 +/- 1.62 L) was significantly greater than mean TLC-XR (R) (5.44 +/- 1.17 L, p less than 0.05). TLC measured radiographically at recovery was strongly correlated (r = 0.94) with TLC measured by plethysmography or helium dilution. We conclude that acute reversible increases in TLC do occur during exacerbations of asthma and that these changes are only readily detected by formal planimetry.

Acute Disease↗
PubMed1990

Bronchiolitis obliterans organizing pneumonia: CT features in 14 patients.

Bronchiolitis obliterans organizing pneumonia is a disease characterized by the presence of granulation tissue within small airways and the presence of areas of organizing pneumonia. We retrospectively reviewed the chest radiographs, CT scans, and biopsy specimens in 14 consecutive patients with proved bronchiolitis obliterans organizing pneumonia. Six patients were immunocompromised because of leukemia or bone-marrow transplantation. In all patients, 10-mm collimation CT scans were available. In 11 of the 14 patients, select 1.5-mm scans were obtained. The CT findings included patchy unilateral (n = 1) or bilateral air-space consolidation (n = 9), small nodular opacities (n = 7), irregular linear opacities (n = 2), bronchial wall thickening and dilatation (n = 6), and small pleural effusions (n = 4). All patients had areas of air-space consolidation, small nodules, or both. A predominantly subpleural distribution of the air-space consolidation was apparent on the radiographs of two patients and on CT scans of six. Pathologically, the nodules and the consolidation represented different degrees of inflammation in bronchioles, alveolar ducts, and alveoli. Although most of the findings were apparent on the radiographs, the CT scans depicted the anatomic distribution and extent of bronchiolitis obliterans organizing pneumonia more accurately than did the plain chest radiographs.

Adult↗
PubMed1989

Chronic diffuse infiltrative lung disease: comparison of diagnostic accuracy of CT and chest radiography.

The accuracies of chest radiography and computed tomography (CT) in the prediction of specific diagnoses in 118 consecutive patients with chronic diffuse infiltrative lung disease (DILD) were compared. The radiographs and CT scans were independently assessed by three observers without knowledge of clinical or pathologic data. The observers listed the three most likely diagnoses in order of probability and recorded the degree of confidence they felt in their first-choice diagnosis on a three-point scale. Confidence level 1 (definite) was reached with 23% of radiographic and 49% of CT scan readings, and the correct diagnosis was made with 77% and 93% of those readings, respectively (P less than .001). The correct first-choice diagnosis regardless of the level of confidence was made with 57% of radiographic and 76% of CT scan readings (P less than .001). The CT scan interpretations were most accurate in silicosis (93%), usual interstitial pneumonia (89%), lymphangitic carcinomatosis (85%), and sarcoidosis (77%). Observers correctly predicted whether a transbronchial or open lung biopsy was indicated with 65% of radiographs and 87% of CT scans (P less than .001). It is recommended that CT be performed before lung biopsy in all patients with chronic DILD.

Adult↗
PubMed1989

Limitations of computed tomography in the assessment of emphysema.

Thirty-eight patients undergoing lobectomy or pneumonectomy for carcinoma had preoperative computed tomography (CT) of the chest. Twenty-seven had both 1.5 mm and 10 mm collimation scans, and eleven had 10 mm collimation images only. These images were analyzed for the extent and severity of emphysema, and the analysis compared to the pathologic findings in the corresponding transverse slice of lung. The latter was graded by a modification of a panel of standards and by a grid system numerically expressing extent and severity. The grid system is theoretically superior to the panel of standards because it allows better quantitation of early emphysema and, contrary to the set of standards, is designed to analyze transverse CT images and corresponding pathologic slices. There was good correlation between the CT score and the pathologic score using the panel of standards (r = 0.81, p less than 0.001) but a lower correlation with the grid system (r = 0.70, p less than 0.001). The correlation improved slightly with 1.5 as compared to 10 mm collimation scans. Close comparison between the CT and grid scores showed that CT was sensitive in demonstrating early distal acinar and irregular emphysema. However, CT consistently underestimated the extent of centriacinar and panacinar emphysema because most lesions less than 0.5 cm in diameter were missed. We conclude that CT is insensitive in detecting the earliest lesions of emphysema.

Humans↗
PubMed1989

High resolution computed tomography and lung function in asbestos-exposed workers with normal chest radiographs.

Asbestos-exposed persons with normal chest radiographs can demonstrate parenchymal abnormalities on high resolution computed tomography (HRCT). We reviewed the HRCT, clinical presentation, and results of pulmonary function tests in 169 asbestos-exposed workers with normal chest radiographs (ILO less than 1/0). The HRCT was normal or near normal in 76 subjects (Group 1), abnormal but indeterminate for asbestosis in 36, and abnormal and suggestive of asbestosis in 57 (Group 2). The indeterminate subjects were excluded from further analysis. The subjects in Groups 1 and 2 were not significantly different in their duration of asbestos exposure, latency, smoking history, or in measurements of airflow obstruction (FEV1/FVC% and %FEV1). Both the vital capacity percent predicted and diffusing capacity percent predicted were significantly lower in the abnormal subjects (Group 2) than in the normal subjects (Group 1) (79.0 versus 86.2, p = 0.005; 78.2 versus 87.1, p = 0.024; independent t test). We conclude that in asbestos-exposed subjects with normal chest radiographs, HRCT can identify a group of subjects with significantly reduced lung function indicative of restrictive lung disease when compared with a group with normal or near-normal HRCT.

Adult↗
PubMed1988

Mediastinal nodes in bronchogenic carcinoma: comparison between CT and mediastinoscopy.

Computed tomography (CT) and mediastinoscopy were compared in 151 patients with bronchogenic carcinoma. In all patients in whom findings at mediastinoscopy were negative, all accessible nodes were either removed or sampled at thoracotomy. Several size criteria for identifying nodes as enlarged on CT scans were compared. The long axis greater than or equal to 15 mm and short axis greater than 10 mm had very low sensitivity (61%), and the long axis greater than 5 mm had a low specificity (23%). CT (long axis greater than 10 mm) allowed sensitivity equal to that of mediastinoscopy (79%) in the detection of mediastinal metastases, but the specificity with CT was lower (65% vs. 100%). In seven of 44 patients with nodes greater than 10 mm on CT scans and with positive findings at mediastinoscopy, tumor was present not in the enlarged nodes but rather in normal-sized nodes in a different nodal station. The sensitivity of CT for actual nodal stations involved with tumor was only 66%. Eighty-three percent of patients with false-negative findings at mediastinoscopy but only 33% of patients with false-negative findings at CT had surgically resectable stage IIIa disease.

Carcinoma, Bronchogenic↗
PubMed1988

"Density mask". An objective method to quantitate emphysema using computed tomography.

We used a computed tomography (CT) scanner program ("density mask") that highlights voxels within a given density range to quantitate emphysema by defining areas of abnormally low attenuation. We compared different density masks, mean lung attenuation, visual assessment of emphysema and the pathologic grade of emphysema in 28 patients undergoing lung resection for tumor. In each patient, a single representative CT image was compared with corresponding pathologic specimens of tissue. There was good correlation between the extent of emphysema as assessed by the density mask and the pathologic grade of emphysema. The optimal attenuation level to define areas of emphysema may vary in different scanners, but, once determined for a particular scanner, the density mask accurately assesses the extent of emphysema and eliminates interobserver and intraobserver variability. It has the added advantage of determining the exact percentage of lung parenchyma showing changes consistent with emphysema.

Adult↗
PubMed1987

Differential diagnosis of bronchiolitis obliterans with organizing pneumonia and usual interstitial pneumonia: clinical, functional, and radiologic findings.

To assess the role of chest radiography in the differential diagnosis of bronchiolitis obliterans organizing pneumonia (BOOP) and usual interstitial pneumonia (UIP), records of 34 patients with biopsy-proved BOOP (16 patients) or UIP (18 patients) were reviewed. Chest radiographs taken before biopsy were available in 26 patients, clinical information in 33, and pulmonary function data in 22. These data were reviewed independently, without knowledge of the pathologic diagnosis. The clinical symptoms of BOOP were similar to those of UIP, although the duration of symptoms was longer in UIP (P less than .05), and the prevalence of systemic symptoms was higher in BOOP (P less than .025). The physical findings were similar except that finger clubbing was more common in patients with UIP than in those with BOOP (P less than .01). There was no significant difference in lung volumes, flows, or diffusing capacity between BOOP and UIP. The chest radiograph showed distinguishing features between UIP and BOOP in 23 of 26 patients. The most characteristic radiologic finding in BOOP was the presence of patchy areas of air-space consolidation (eight of 11 patients).

Adult↗
PubMed1987

Usual interstitial pneumonia: correlation of CT with clinical, functional, and radiologic findings.

Correlation between disease extent on computed tomographic (CT) scans and severity of clinical and functional impairment was obtained in 23 patients with usual interstitial pneumonia (UIP) by review of the clinical data, pulmonary function tests, chest radiographs, and CT scans. The CT scans and chest radiographs were each read twice by two independent observers. Disease extent was assessed on CT scans by a visual score (0%-100% involvement of the lung parenchyma) and on the radiograph by the International Labour Office classification. There was good intraobserver and interobserver agreement for both CT and radiograph scores (all r greater than or equal to .71). CT scans gave a better estimate of disease extent and showed more extensive honeycombing than did the radiograph. A significant correlation was found between the extent of disease as assessed with CT and the severity of dyspnea (r = .62, P less than .001), as well as between CT and impairment in gas exchange as assessed by the diffusing capacity (r = .64, P less than .001). There was poor correlation between disease severity as assessed with chest radiography and the clinical and functional variables (all r less than or equal to .39).

Adult↗
PubMed1987

Disease activity in idiopathic pulmonary fibrosis: CT and pathologic correlation.

Computed tomography (CT) scans were compared with pathologic determinants of disease activity in 12 patients with idiopathic pulmonary fibrosis. The theory was that intraalveolar and interstitial cellularity would result in areas of opacification of air spaces on CT scans. All patients underwent open lung biopsy, and disease activity was assessed with a pathologic grading system. Seven patients had mild disease activity, five had moderate to marked disease activity. Opacification of air spaces was patchy in distribution, predominantly peripheral, and seen better on 1.5-mm rather than 10-mm collimation scans. Disease activity on CT scans was graded independently from 0 to 3 based on the presence and relative density of the areas of air space consolidation compared with the surrounding parenchyma. The pathologic score was significantly greater in the patients with high CT scores than in those with low CT scores (P = .001). Five patients with marked disease activity and five of seven patients with mild disease activity were correctly identified. CT may be useful in the assessment of disease activity in idiopathic pulmonary fibrosis.

Adult↗