Screening of miners and millers at decreasing levels of asbestos exposure: comparison of chest radiography and thin-section computed tomography.

BACKGROUND: Chest radiography (CXR) is inferior to Thin-section computed tomography in the detection of asbestos related interstitial and pleural abnormalities. It remains unclear, however, whether these limitations are large enough to impair CXR´s ability in detecting the expected reduction in the frequency of these asbestos-related abnormalities (ARA) as exposure decreases. METHODS: Clinical evaluation, CXR, Thin-section CT and spirometry were obtained in 1418 miners and millers who were exposed to progressively lower airborne concentrations of asbestos. They were separated into four groups according to the type, period and measurements of exposure and/or procedures for controlling exposure: Group I (1940-1966/tremolite and chrysotile, without measurements of exposure and procedures for controlling exposure); Group II (1967-1976/chrysotile only, without measurements of exposure and procedures for controlling exposure); Group III (1977-1980/chrysotile only, initiated measurements of exposure and procedures for controlling exposure) and Group IV (after 1981/chrysotile only, implemented measurements of exposure and a comprehensive procedures for controlling exposure). RESULTS: In all groups, CXR suggested more frequently interstitial abnormalities and less frequently pleural plaques than observed on Thin-section CT (p<0.050). The odds for asbestosis in groups of decreasing exposure diminished to greater extent at Thin-section CT than on CXR. Lung function was reduced in subjects who had pleural plaques evident only on Thin-section CT (p<0.050). In a longitudinal evaluation of 301 subjects without interstitial and pleural abnormalities on CXR and Thin-section CT in a previous evaluation, only Thin-section CT indicated that these ARA reduced as exposure decreased. CONCLUSIONS: CXR compared to Thin-section CT was associated with false-positives for interstitial abnormalities and false-negatives for pleural plaques, regardless of the intensity of asbestos exposure. Also, CXR led to a substantial misinformation of the effects of the progressively lower asbestos concentrations in the occurrence of asbestos-related diseases in miners and millers.

COPD phenotypes in biomass smoke- versus tobacco smoke-exposed Mexican women.

We hypothesised that biomass smoke exposure is associated with an airway-predominant chronic obstructive pulmonary disease (COPD) phenotype, while tobacco-related COPD is associated with an emphysema-predominant phenotype. In this cross-sectional study, female never-smokers with COPD and biomass exposure (n=21) and female ex-cigarette smokers with COPD without biomass exposure (n=22) completed computed tomography (CT) at inspiration and expiration, pulmonary function, blood gas, exercise tolerance, and quality of life measures. Two radiologists scored the extent of emphysema and air trapping on CT. Quantitative emphysema severity and distribution and airway wall thickness were calculated using specialised software. Women in the tobacco group had significantly more emphysema than the biomass group (radiologist score 2.3 versus 0.7, p=0.001; emphysema on CT 27% versus 19%, p=0.046; and a larger size of emphysematous spaces, p=0.006). Women in the biomass group had significantly more air trapping than the tobacco group (radiologist score 2.6 and 1.5, respectively; p=0.02) and also scored lower on the symptom, activities and confidence domains of the quality of life assessment and had lower oxygen saturation at rest and during exercise (p<0.05). Biomass smoke exposure is associated with less emphysema but more air trapping than tobacco smoke exposure, suggesting an airway-predominant phenotype.

Lung diffusing capacity relates better to short-term progression on HRCT abnormalities than spirometry in mild asbestosis.

BACKGROUND: Pulmonary function tests (PFT), particularly spirometry and lung diffusing capacity for carbon monoxide (DL(CO) ), have been considered useful methods for the detection of the progression of interstitial asbestos abnormalities as indicated by high-resolution computed tomography (HRCT). However, it is currently unknown which of these two tests correlates best with anatomical changes over time. METHODS: In this study, we contrasted longitudinal changes (3-9 years follow-up) in PFTs at rest and during exercise with interstitial abnormalities evaluated by HRCT in 63 ex-workers with mild-to-moderate asbestosis. RESULTS: At baseline, patients presented with low-grade asbestosis (Huuskonen classes I-II), and most PFT results were within the limits of normality. In the follow-up, most subjects had normal spirometry, static lung volumes and arterial blood gases. In contrast, frequency of DL(CO) abnormalities almost doubled (P < 0.05). Twenty-three (36.5%) subjects increased the interstitial marks on HRCT. These had significantly larger declines in DL(CO) compared to patients who remained stable (0.88 vs. 0.31 ml/min/mm Hg/year and 3.5 vs. 1.2%/year, respectively; P < 0.05). In contrast, no between-group differences were found for the other functional tests, including spirometry (P > 0.05). CONCLUSIONS: These data demonstrate that the functional consequences of progression of HRCT abnormalities in mild-to-moderate asbestosis are better reflected by decrements in DL(CO) than by spirometric changes. These results might have important practical implications for medico-legal evaluation of this patient population.

Illustrated Brazilian consensus of terms and fundamental patterns in chest CT scans.

The objective of this new Brazilian consensus is to update and to continue the standardization of the principal terms and fundamental patterns in chest CT scans in Portuguese. There is a succinct definition of the principal terms used to describe chest CT findings, as well as illustrations of classic examples. The group of authors comprised radiologists specializing in chest radiology and holding membership in the Brazilian College of Radiology and Diagnostic Imaging, as well as pulmonologists having a special interest in diagnostic imaging and holding membership in the Brazilian Thoracic Association.

Consenso brasileiro ilustrado sobre a terminologia dos descritores e padrões fundamentais da TC de tórax / Illustrated Brazilian consensus of terms and fundamental patterns in chest CT scans

O objetivo deste novo consenso brasileiro é atualizar e dar continuidade à padronização da terminologia dos principais descritores e padrões fundamentais da TC de tórax em língua portuguesa. Este consenso contém uma descrição sucinta dos principais termos utilizados na TC de tórax e ilustrações de exemplos clássicos. O grupo de autores é formado por médicos radiologistas membros do Colégio Brasileiro de Radiologia e Diagnóstico por Imagem, especializados em radiologia torácica, e por pneumologistas membros da Sociedade Brasileira de Pneumologia e Tisiologia, com particular interesse em diagnóstico por imagem.

The objective of this new Brazilian consensus is to update and to continue the standardization of the principal terms and fundamental patterns in chest CT scans in Portuguese. There is a succinct definition of the principal terms used to describe chest CT findings, as well as illustrations of classic examples. The group of authors comprised radiologists specializing in chest radiology and holding membership in the Brazilian College of Radiology and Diagnostic Imaging, as well as pulmonologists having a special interest in diagnostic imaging and holding membership in the Brazilian Thoracic Association.

Idiopathic interstitial pneumonias.

The idiopathic interstitial pneumonias (IIPs) are a group of diffuse parenchymal lung diseases of unknown etiology characterized by the presence of various degrees of inflammation and fibrosis. Confident definitive diagnosis of the various IIPs requires dynamic interaction among clinicians, radiologists, and pathologists to arrive at a clinico-radiologic-pathologic diagnosis. The aims of this manuscript are to summarize the characteristic clinical and histologic manifestations, and to describe and illustrate the high-resolution computed tomography manifestations of the IIPs. The focus will be on idiopathic pulmonary fibrosis (idiopathic usual interstitial pneumonia), nonspecific interstitial pneumonia, cryptogenic organizing pneumonia, and acute interstitial pneumonia. High-resolution computed tomography plays an important role in the initial diagnosis, the assessment of disease extent, the likelihood of response to treatment and prognosis, and the assessment of complications.

Manifestações intratorácicas das doenças do colágeno na tomografia computadorizada de alta resolução do tórax / Intrathoracic manifestations of collagen vascular diseases on high-resolution chest computed tomography

As manifestações intratorácicas das doenças do colágeno são bastante comuns. O padrão e a freqüência de comprometimento dependem do tipo específico de doença do colágeno, que pode envolver um ou vários compartimentos simultaneamente, tais como parênquima, vias aéreas, artérias pulmonares, pleura, e pericárdio. As manifestações mais importantes incluem as pneumonias intersticiais difusas e a hipertensão pulmonar, que em conjunto representam as principais causas de mortalidade e morbidade nesses pacientes. O acometimento pulmonar, pleural e de via aérea pode ser também secundário a terapêutica instituída ou ser decorrente de processos infecciosos bacterianos ou por germes oportunistas, por causa da imunossupressão. Nesta revisão os autores sumarizam as manifestações intratorácicas e o diagnóstico diferencial das principais doenças do colágeno na tomografia computadorizada de alta resolução do tórax.

Intrathoracic manifestations of collagen vascular diseases are very common. The frequency of intrathoracic manifestations and the pattern of abnormality are variable depending on the type of collagen vascular disease and may simultaneously involve one or more of the following: lung parenchyma, airways, pulmonary vessels, pericardium, and pleura. Most significant manifestations include diffuse interstitial pneumonia and pulmonary hypertension which together represent the main causes of morbidity and mortality of these patients. Pulmonary, airway and pleural involvement may also be secondary to the therapy adopted for management of the disease, or result from bacterial pneumonia or opportunistic infection. In the present review, the authors summarize the main intrathoracic manifestations of collagen vascular diseases and the differential diagnosis on high-resolution chest computed tomography.

Organizing pneumonia as a manifestation of Pneumocystis jiroveci immune reconstitution syndrome in HIV-positive patients: report of 2 cases.

Organizing pneumonia (OP) is a nonspecific response to various forms of lung injury. Although patients with human immunodeficiency virus (HIV) infection tend to develop several respiratory disorders, especially infections and malignances, the association of HIV infection and OP is unusual. Pneumocystis jiroveci infection is also rarely associated with OP. We describe the radiologic findings in 2 HIV-positive patients who shortly after introduction of highly active antiretroviral therapy, presented with clinical and radiologic deterioration, despite elevation of the CD4 cell count and viral load decrease. In both patients, clinical and radiologic features were consistent with OP and lung biopsy revealed OP associated with P. jiroveci infection. These findings are consistent with immune reconstitution syndrome due to P. jiroveci.

Nonspecific interstitial pneumonia and idiopathic pulmonary fibrosis: changes in pattern and distribution of disease over time.

PURPOSE: To retrospectively assess the change in disease pattern of nonspecific interstitial pneumonia (NSIP) and idiopathic pulmonary fibrosis (IPF) findings seen at thin-section computed tomography (CT) at long-term follow-up and to compare the same with initial findings at CT. MATERIALS AND METHODS: The study included 48 patients (28 men, 20 women; mean age, 57.5 years) with biopsy-proved NSIP (n = 23) or IPF (n = 25) who underwent CT at initial diagnosis and at follow-up 34-155 months later. The CT scans were randomized and reviewed by two independent thoracic radiologists for pattern and distribution of ground-glass opacity (GGO), reticulation, traction bronchiectasis and bronchiolectasis, and honeycombing. Statistical analysis was performed by using nonparametric methods and univariate logistic regression. RESULTS: Follow-up CT in patients with NSIP showed marked decrease in the extent of GGO, increase in reticulation, and a greater likelihood of peripheral distribution (all P < .05). At presentation, the CT findings were interpreted as suggestive of NSIP in 18 of 23 patients with NSIP and indeterminate or suggestive of IPF in five. In five (28%) of 18 patients with initial findings suggestive of NSIP, the follow-up CT scans were interpreted as more suggestive of IPF. No CT features seen at presentation allowed distinction between patients with NSIP that maintained an NSIP pattern at follow-up and those that progressed to an IPF pattern. CONCLUSION: At follow-up CT, 28% of patients with initial CT findings suggestive of NSIP progressed to findings suggestive of IPF. Similar initial CT findings for NSIP may have different imaging outcomes.

Chronic hypersensitivity pneumonitis: differentiation from idiopathic pulmonary fibrosis and nonspecific interstitial pneumonia by using thin-section CT.

PURPOSE: To retrospectively assess the accuracy of thin-section computed tomography (CT) in distinguishing chronic hypersensitivity pneumonitis (HP) from idiopathic pulmonary fibrosis (IPF) and nonspecific interstitial pneumonia (NSIP), with histologic results as the reference standard. MATERIALS AND METHODS: This retrospective study was approved by the institutional research boards of the participating centers, and informed consent was waived. There was HIPAA compliance for all U.S. patients. The study included 66 patients (36 men, 30 women; mean age, 58.8 years +/- 10.9 [standard deviation]) with proved chronic HP (n = 18), IPF (n = 23), or NSIP (n = 25) who underwent CT. Two independent readers assessed the CT images, made a first-choice diagnosis, and noted the degree of confidence in the diagnosis. A general linear model was used to identify CT features that independently differentiated chronic HP from IPF and NSIP. Weighted kappa statistic was used to assess interobserver agreement. RESULTS: The CT features that best differentiated chronic HP were lobular areas with decreased attenuation and vascularity, centrilobular nodules, and absence of lower zone predominance of abnormalities (P < or = .008). The features that best differentiated NSIP were relative subpleural sparing, absence of lobular areas with decreased attenuation, and lack of honeycombing (P < or = .002). The features that best differentiated IPF were basal predominance of honeycombing, absence of relative subpleural sparing, and absence centrilobular nodules (P < or = .004). A confident diagnosis was made in 70 (53%) of 132 readings. This diagnosis was correct in 66 (94%) of 70 readings. The accuracy for the entire cohort was 80%. Interobserver agreement for confident diagnosis was good to excellent (kappa = 0.77-0.96). CONCLUSION: Characteristic CT features of chronic HP, IPF, and NSIP allow confident distinction between these entities in approximately 50% of patients.

Asbestos-related disease: progression of parenchymal abnormalities on high-resolution CT.

PURPOSE: To evaluate the changes over time in the pattern and extent of parenchymal abnormalities in asbestos-exposed workers after cessation of exposure and to compare 3 proposed semiquantitative methods with a careful side-by-side comparison of the initial and the follow-up computed tomography (CT) images. MATERIALS AND METHODS: The study included 52 male asbestos workers (mean age+/-SD, 62.2 y+/-8.2) who had baseline high-resolution CT after cessation of exposure and follow-up CT 3 to 5 years later. Two independent thoracic radiologists quantified the findings according to the scoring systems proposed by Huuskonen, Gamsu, and Sette and then did a side-by-side comparison of the 2 sets of scans without awareness of the dates of the CT scans. RESULTS: There was no difference in the prevalence of the 2 most common parenchymal abnormalities (centrilobular small dotlike or branching opacities and interstitial lines) between the initial and follow-up CT scans. Honeycombing (20%) and traction bronchiectasis and bronchiolectasis (50%) were seen more commonly on the follow-up CT than on the initial examination (10% and 33%, respectively) (P=0.01). Increased extent of parenchymal abnormalities was evident on side-by-side comparison in 42 (81%) patients but resulted in an increase in score in at least 1 semiquantitative system in only 16 (31%) patients (all P>0.01, signed test). CONCLUSIONS: The majority of patients with previous asbestos exposure show evidence of progression of disease on CT at 3 to 5 years follow-up but this progression is usually not detected by the 3 proposed semiquantitative scoring schemes.

Acute exacerbation of chronic interstitial pneumonia: high-resolution computed tomography and pathologic findings.

PURPOSE: To review the high-resolution computed tomography (CT) and histologic findings of acute exacerbation of chronic interstitial pneumonia and to assess the potential value of CT and histologic findings in predicting prognosis. MATERIALS AND METHODS: The study included 24 patients with clinical and histologic diagnosis of acute exacerbation of chronic interstitial pneumonia who underwent CT within 1 month before biopsy or autopsy. The final diagnosis was acute exacerbation of idiopathic pulmonary fibrosis (n=12), usual interstitial pneumonia associated with connective tissue disorders (n=5), idiopathic nonspecific interstitial pneumonia (n=4), and nonspecific interstitial pneumonia associated with connective tissue disorders (n=3). RESULTS: The main CT findings consisted of bilateral ground-glass opacities (100%) and consolidation (71%) superimposed on a reticular pattern. The ground-glass opacities and/or consolidation were diffuse in 54% of the cases, multifocal in 21%, and peripheral in 25%. The histologic patterns of acute injury consisted of diffuse alveolar damage (n=20), acute organizing pneumonia (OP) (n=3), and extensive fibroblastic foci (n=1). Eight (33%) patients survived the acute episode, including all 3 patients with OP and the patient with extensive fibroblastic foci (P=0.01). The survivors included 3 of 13 (23%) patients with diffuse parenchymal opacification, 2 of 5 (40%) patients with multifocal, and 3 of 6 (50%) patients with peripheral opacification on CT. CONCLUSIONS: The CT findings of acute exacerbation of chronic interstitial pneumonia consist of diffuse, multifocal, or peripheral parenchymal opacification superimposed on reticulation. Histologic findings of OP are superior to CT in predicting prognosis.

Pulmonary complications of illicit drug use: differential diagnosis based on CT findings.

OBJECTIVE: The aim of this manuscript is to summarize an approach to the differential diagnosis of the pulmonary complications of illicit drug use based on the computed tomography findings. CONCLUSIONS: The various pulmonary complications of illicit drug use result in 5 main patterns of parenchymal abnormality: nodules, ground-glass opacities, consolidation, air trapping, and emphysema. Other thoracic manifestations of illicit drug use include pulmonary arterial hypertension, pneumomediastinum, bacterial endocarditis, discitis, and septic arthritis.

Pulmonary artery aneurysms and pseudoaneurysms in adults: findings at CT and radiography.

OBJECTIVE: The purpose of this pictorial essay is to illustrate the radiologic manifestations of pulmonary artery aneurysms and pseudoaneurysms with emphasis on the findings on contrast-enhanced CT. CONCLUSION: Pulmonary artery aneurysms and pseudoaneurysms are uncommon. Most are caused by trauma, often iatrogenic, infection, and Behçet's syndrome. Less common causes include pulmonary hypertension, congenital heart disease, neoplasms, and connective tissue disease. Recognition of pulmonary artery aneurysms and pseudoaneurysms is important because of the high morbidity and mortality rates of rupture.

Hypersensitivity pneumonitis: spectrum of high-resolution CT and pathologic findings.

OBJECTIVE: The purpose of this article is to illustrate the spectrum of pathologic and high-resolution CT features of hypersensitivity pneumonitis (HP). CONCLUSION: High-resolution CT plays an important role in the diagnosis of HP. A confident diagnosis of subacute HP is based on the presence of ground-glass opacities, poorly defined centrilobular nodules, and mosaic attenuation on inspiratory images and of air trapping on expiratory CT images. Chronic HP is characterized on high-resolution CT by the presence of reticulation due to fibrosis superimposed on findings of subacute HP. Histologically, subacute HP is characterized by the presence of cellular bronchiolitis, noncaseating granulomas, and bronchiolocentric lymphocytic interstitial pneumonitis. Areas of organizing pneumonia also may be seen. The high-resolution CT and pathologic features of chronic HP frequently overlap with those of nonspecific interstitial pneumonia and usual interstitial pneumonia. Awareness of the various manifestations of HP is important for early diagnosis and management.

Acute exacerbation (acute lung injury of unknown cause) in UIP and other forms of fibrotic interstitial pneumonias.

Acute exacerbation of usual interstitial pneumonia (UIP) is a condition in which patients with UIP, and occasionally other forms of fibrotic interstitial lung disease, develop rapid respiratory failure, accompanied by extensive radiologic infiltrates. The pathologic features of this condition are ill-defined in the literature and the outcome is unclear. We report 12 such patients, 9 with underlying UIP, 2 with underlying fibrotic nonspecific interstitial pneumonia, and 1 with underlying chronic hypersensitivity pneumonitis, who underwent surgical lung biopsy for diagnosis. High-resolution computed tomography data were available in 11 cases and showed the presence of extensive bilateral ground-glass opacities, sometimes accompanied by focal consolidation, superimposed on underlying fibrosis. Three microscopic patterns of acute lung injury were seen: diffuse alveolar damage (DAD), organizing pneumonia (OP), and a pattern of numerous very large fibroblast foci superimposed on underlying fibrosis. After the biopsy, all patients were treated with steroids, in some instances accompanied by cyclophosphamide or azathioprine. Ten patients survived the acute episode and were discharged with survival times of 1 to 11 months; of these cases, 6 showed a pattern of OP or OP plus extensive fibroblast foci; 2 a pattern of extensive fibroblast foci only; and 2 a pattern of DAD. Both patients who died had histologic DAD. We conclude that acute exacerbation of UIP and other fibrotic lung diseases produces a variety of pathologic patterns on biopsy, and that patients with OP or extensive fibroblast foci as the acute pattern seem to do better than those with DAD. Our data also imply that survival (of the acute episode) may be better than the literature suggests.

Diffuse lung cysts in lymphoid interstitial pneumonia: high-resolution CT and pathologic findings.

Lymphoid interstitial pneumonia is part of a spectrum of pulmonary lymphoproliferative disorders that range from benign, small, and airway-centered cellular infiltrates (follicular bronchiolitis, nodular lymphoid hyperplasia) to low-grade malignant lymphoma. Most of the cases occur in patients with underlying autoimmune disease or immunodeficiency. The characteristic high-resolution computed tomography findings consist of diffuse ground-glass opacities, ill-defined centrilobular nodules, bronchovascular thickening, interlobular septal thickening, and scattered thin-walled cysts. The cysts may be seen in up to 80% of the patients and are typically few in number and measure less than 3 cm in diameter. This case illustrates extensive cysts as the predominant high-resolution computed tomography finding of idiopathic lymphoid interstitial pneumonia in a 64-year-old man who underwent unilateral lung transplant. Such extensive cystic disease and lung transplantation treatment has not been previously described.

Drug-induced lung diseases: most common reaction patterns and corresponding high-resolution CT manifestations.

Drug-induced lung disease is an increasingly common cause of morbidity and mortality. The diagnosis is based on clinical history and consistent radiologic findings. Lung biopsy is performed in a small percentage of cases. High-resolution CT may demonstrate parenchymal abnormalities in patients with normal radiographs and provides a better depiction of the pattern and distribution of findings. Knowledge of the most common high-resolution CT manifestations and the corresponding histologic patterns is important for early recognition and proper management of drug-induced lung disease.

Modelo de interpretação da tomografia computadorizada de alta resolução do diagnóstico diferencial das doenças intersticiais crônicas / High-resolution computed tomography interpretation model for differential diagnosis of chronic interstitial lung diseases

O reconhecimento e o diagnóstico diferencial dos diversos padrões da tomografia computadorizada de alta resolução (TCAR) são de fundamental importância na avaliação das doenças pulmonares difusas. Existem vários padrões de TCAR descritos na literatura, sendo alguns deles superponíveis. A interpretação desses padrões pode ser uma tarefa difícil, particularmente para residentes e radiologistas não especializados em tórax. Os autores ilustram os achados característicos da TCAR nas doenças pulmonares intersticiais crônicas e propõem um modelo simplificado de interpretação desses achados, baseado no padrão e na distribuição da doença. O algoritmo inclui os seis principais padrões de anormalidade identificados na TCAR: septal, reticular, cístico, nodular, de atenuação em vidro fosco e consolidação parenquimatosa.