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C A Staples

Publications and source records attributed to C A Staples.

At least 37 records · Page 2Linked to original sources
PubMed1995

Invasive pulmonary aspergillosis in AIDS: radiographic, CT, and pathologic findings.

PURPOSE: To review the radiographic and computed tomographic (CT) manifestations of invasive pulmonary aspergillosis and to correlate the imaging and pathologic findings in patients with acquired immunodeficiency syndrome (AIDS). MATERIALS AND METHODS: Chest radiographs, CT scans, and pathologic specimens were reviewed retrospectively in 10 AIDS patients with proved invasive pulmonary aspergillosis. RESULTS: The most common radiographic finding was the presence of thick-walled cavitary lesions. Less common findings included nodules, consolidation, and pleural effusion. CT depicted more nodules and cavities than did radiography. The predominant pathologic abnormalities consisted of tissue invasion and abscess formation and angioinvasion with or without infarction. All patients had infection with Aspergillus fumigatus as well as other pathogens, the most common being cytomegalovirus and Pseudomonas aeruginosa. CONCLUSION: Thick-walled cavitary lesions are the most common radiologic manifestation of invasive pulmonary aspergillosis in AIDS. The findings are more numerous and better defined on CT scans. The radiologic findings reflect a spectrum of pathologic abnormalities.

AIDS-Related Opportunistic Infections↗
PubMed1995

Intrathoracic lymphoproliferative disorders in the immunocompromised patient: CT findings.

PURPOSE: To assess the computed tomographic (CT) findings of intrathoracic lymphoproliferative disorders in the immunocompromised patient. MATERIALS AND METHODS: The authors retrospectively reviewed CT scans of the chest in 18 consecutive patients with pathologically proved intrathoracic lymphoproliferative disorders. Twelve patients had the acquired immunodeficiency syndrome (AIDS), and six were receiving immunosuppressive therapy. Final diagnosis included AIDS-related diffuse lymphoid hyperplasia (n = 1), lymphocytic interstitial pneumonia (LIP) (n = 3), posttransplantation lymphoproliferative disorders (PTLDs) (n = 4), and lymphoma (n = 10). RESULTS: Diffuse areas of ground-glass attenuation were found in the patient with lymphoid hyperplasia and the three patients with LIP. The four patients with PTLDs had multiple, well-circumscribed pulmonary nodules, and nodules in three of the four patients had a halo of ground-glass attenuation. Nine of the 10 patients with lymphoma had well-circumscribed nodules or nodules with consolidation. Mediastinal lymph node enlargement was present in two patients with PTLDs and three patients with lymphoma. CONCLUSION: The intrathoracic CT findings of lymphoproliferative disorders appear to be similar in immunocompromised patients with and without AIDS and are usually extranodal.

Acquired Immunodeficiency Syndrome↗
PubMed1995

Measurement of lung expansion with computed tomography and comparison with quantitative histology.

The total and regional lung volumes were estimated from computed tomography (CT), and the pleural pressure gradient was determined by using the milliliters of gas per gram of tissue estimated from the X-ray attenuation values and the pressure-volume curve of the lung. The data show that CT accurately estimated the volume of the resected lobe but overestimated its weight by 24 +/- 19%. The volume of gas per gram of tissue was less in the gravity-dependent regions due to a pleural pressure gradient of 0.24 +/- 0.08 cmH2O/cm of descent in the thorax. The proportion of tissue to air obtained with CT was similar to that obtained by quantitative histology. We conclude that the CT scan can be used to estimate total and regional lung volumes and that measurements of the proportions of tissue and air within the thorax by CT can be used in conjunction with quantitative histology to evaluate lung structure.

Biopsy↗
PubMed1994

Chronic infiltrative lung disease: comparison of diagnostic accuracies of radiography and low- and conventional-dose thin-section CT.

PURPOSE: To compare the accuracy of low-dose thin-section computed tomography (CT), chest radiography, and conventional-dose thin-section CT in diagnosis of chronic infiltrative lung disease (CILD). MATERIALS AND METHODS: Chest radiographs and low-dose (80-mAs) and conventional-dose (340-mAs) thin-section (1.5-mm) CT scans from 50 patients with CILD and 10 healthy control subjects were randomized and analyzed retrospectively. For CT, three images were obtained: at the aortic arch, at the tracheal carina, and 1 cm above the right hemidiaphragm. Two independent observers listed three likely diagnoses and recorded the degree of confidence in their first choice. RESULTS: A correct first-choice diagnosis was made more often with either CT technique than with radiography (P < .02). A high confidence level in the diagnosis was reached in 42% of radiographic, 61% of low-dose CT, and 63% of conventional-dose CT interpretations, which were correct in 92%, 90%, and 96% of the studies, respectively. CONCLUSION: The superior diagnostic accuracy of low-dose thin-section CT was achieved without an increase in effective radiation dose.

Adult↗
PubMed1994

Diagnosis of thoracic complications in AIDS: accuracy of CT.

OBJECTIVE: The purpose of this study was to assess the accuracy of CT interpretation in the diagnosis of thoracic complications of AIDS. If CT is accurate, more invasive diagnostic procedures can be avoided. MATERIALS AND METHODS: We reviewed the CT scans of 102 patients who had AIDS with proved thoracic complications and 20 HIV-positive patients without active intrathoracic disease. The scans were independently assessed by two observers from a different institution who did not know the clinical or pathologic data. The observers listed the three most likely diagnoses in order of probability and recorded the degree of confidence in their first-choice diagnosis. Imaging diagnoses were compared with final diagnoses based on results of sputum cultures, bronchoscopy, fine-needle aspiration, mediastinoscopy, open lung biopsy, autopsy, gallium scans, other clinical data, and extensive follow-up. RESULTS: Nineteen of the 20 cases in which no active disease was present were correctly identified by one observer, and 18 were correctly identified by the other. All 102 cases of active disease were correctly identified as abnormal by one observer, and 101 cases were identified as abnormal by the second observer. The correct first-choice diagnosis, regardless of the degree of confidence, was made in 66% of the cases. A confident diagnosis was made in 48% of all cases, and the observers were correct in 92% of those cases. There was good agreement between the two observers in the confident diagnosis based on CT (kappa statistic = 0.71). The interpretations of CT scans were most often accurate in the confident diagnosis of pneumocystis pneumonia (94%) and Kaposi's sarcoma (90%) and in the exclusion of active thoracic disease (93%). CONCLUSION: Certain findings on chest CT scans allow confident diagnoses of specific complications in patients with AIDS. CT-based diagnosis may preclude more invasive diagnostic procedures in selected cases.

AIDS-Related Opportunistic Infections↗
PubMed1993

Pulmonary talcosis: CT findings in three cases.

The authors describe the computed tomographic (CT) appearances in three patients with pulmonary talcosis resulting from chronic intravenous drug abuse. There was widespread ground-glass attenuation in one case and an appearance similar to that of progressive massive fibrosis in two cases. In the latter cases, there were confluent perihilar masses with areas of high attenuation. While the CT appearances may be suggestive of pulmonary talcosis, tissue sampling is required for definitive diagnosis.

Adult↗
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↗