Normal High-resolution Computed Tomography Research Articles

High-resolution CT in childhood rheumatic lung disease

Childhood rheumatic diseases are multi-system diseases which affect connective tissue of whole body and lung is one of the main target organs. The review focus on the utility of high-resolution computed tomography (HRCT)in childhood rheumatic lung disease, including HRCT technique, the normal and abnormal HRCT imaging appearances,then emphasizes and illustrates HRCT imaging futures of several childhood rheumatic lung diseases. Key words: High-resolution CT; Children; Rheumatism; Lung

The radiological patterns of interstitial change at an early phase: Over a 4-year follow-up

The identification of early phase interstitial changes may influence the understanding of idiopathic interstitial pneumonitis. This study aimed to clarify its radiological patterns and the association with smoking. The subjects underwent low-dose computed tomography to screen lung cancer. The selected subjects with interstitial changes were monitored for the precise morphology of interstitial changes using a high-resolution computed tomography (HRCT) scan. The subjects were classified into normal and abnormal HRCT subjects. The radiological findings on the HRCT scan, serum Klebs von der Lungen-6 (KL-6), surfactant protein (SP)-A, SP-D, pulmonary function, and computed tomography (CT) scores were analyzed. Abnormal HRCT subjects were classified based on the radiological patterns, and were followed-up over a 4-year period. HRCT abnormalities suggesting interstitial changes were identified in 80 of 3079 subjects. Seven subjects with honeycombing and 14 with combined pulmonary fibrosis and emphysema (CPFE) were identified. The frequencies of sex (male) and smoking in the subjects with honeycombing was higher than that of other patterns. The smoking history and the levels of serum KL-6, SP-A, and SP-D in abnormal HRCT subjects were significantly higher than those in normal HRCT subjects. Thirty-two of 73 abnormal HRCT subjects showed a progression of the CT scores in a chest HRCT over a 4-year period. Eighteen abnormal HRCT current smokers were included in the progression of CT scores. HRCT patterns, excluding interlobular septal thickening, show the progression of CT scores. Smokers with CT abnormalities may have a tendency to demonstrate worsening interstitial changes.

Airway inflammation in employees involved in cultivating Japanese mushrooms (bunashimeji)

Chronic inhalation of spores may cause respiratory symptoms such as productive cough and sputum. The purpose of this study was to determine the clinical pathophysiology of airway inflammation caused by bunashimeji spores and to investigate whether the spores have direct toxic inflammatory effects. Sensitized employees with respiratory symptoms and a stimulation index (SI) > 200%, and non-sensitized employees with a SI < 200% were enrolled. They underwent sputum induction and chest high-resolution computed tomography (HRCT). The in vitro effect of bunashimeji spore solutions on normal human bronchial epithelial (NHBE) cell cultures was investigated using the air-liquid interface method. Bunashimeji spore solution was added at 10(4) or 10(6) spores per 20 microL/well. The interleukin (IL)-8 and epithelial neutrophil-activating peptide-78 (ENA-78) concentrations in the medium and IL-8 mRNA expression of NHBE cells were assessed after each stimulation. Sensitized employees were divided into 14 with normal HRCT and 9 with abnormal HRCT. Fifteen of the sensitized group and five of the non-sensitized group had a productive cough and sputum. The neutrophil counts in induced sputum were significantly higher in subjects with abnormal HRCT than in those with normal HRCT. IL-8 and ENA-78 concentrations following stimulation with 10(4) and 10(6) spores were significantly increased compared with PBS only on day 9. IL-8 mRNA expression due to spore stimulation was significantly increased compared with control. IL-8 mRNA expression with 10(6) spore stimulation was significantly increased on days 6 and 12 compared with 10(4) spores. The inhalation of spores directly produces toxic inflammatory effects in the airways, independent of the degree of sensitization.

Inspiratory and Expiratory High-Resolution Computed Tomography (HRCT) in Patients with Chemical Warfare Agents Exposure

Chemical warfare agents (CWA) including sulfur mustard (SM) were commonly used in Iran–Iraq war. Respiratory problems are the greatest cause of long-term disability among people who had combat exposure to SM. High-resolution computed tomography (HRCT) has been accepted as the imaging modality of choice in these patients. We used expiratory HRCT findings in comparison to inspiratory HRCT for demonstration of pulmonary damage in these patients. HRCT in deep inspiration as well as full expiration was performed in 473 patients with a history of chemical gas exposure during the war and the results were compared. The study was prospective during 1 yr. Of 473 patients, 366 (77.38%) showed normal HRCT in deep inspiration; however, on corresponding expiratory cuts, 263 (71.86%) had abnormalities. The most frequent abnormal finding in expiration was patchy air trapping (77.77%). We conclude that exposure to SM causes pulmonary complications resulting in disability in the affected patients; however, HRCT in inspiration is normal in most of the affected patients. Expiratory HRCT showed patchy air trapping as the most common finding, which is suggestive of small air way diseases such as bronchiolitis obliterans; therefore it is recommended to do HRCT both in deep inspiration and full expiration in patients with a history of CWA exposure.

Multiple-breath inert gas washout and spirometry versus structural lung disease in cystic fibrosis

Background: A sensitive and valid non-invasive marker of early cystic fibrosis (CF) lung disease is sought. The lung clearance index (LCI) from multiple-breath washout (MBW) is known to detect abnormal...

Radiological and functional assessment of pulmonary involvement in the rheumatoid arthritis patients

The aim was to evaluate the findings of high resolution computed tomography (HRCT) and pulmonary function tests (PFT) in the rheumatoid arthritis (RA) patients with and without pulmonary symptoms and to determine their role in prediction of respiratory system involvement. Among 54 consecutive RA patients, 22 (41%) were symptomatic and 32 (59%) were asymptomatic after detailed respiratory examination. Abnormal findings in PFTs were present in 10 (45%) symptomatic and 15 (47%) asymptomatic patients. PFT results were similar in both groups. A total of 18 (82%) symptomatic and 16 (50%) asymptomatic patients had abnormalities in HRCT scans. About 16 (80%) of 20 patients with normal HRCT scans had no pulmonary symptoms at all and we noted a significant correlation (P < 0.05). HRCT was more useful mean than PFTs in evaluation of pulmonary involvement in the RA patients; however, no correlation was present between various respiratory symptoms and abnormal findings both in PFTs and HRCT scans.

Loss of Anteroposterior Intralobar Attenuation Gradient of the Lung: Correlation with Pulmonary Function

Since the initial description of an intralobar attenuation gradient by Webb et al, it has been suggested that departure from the intralobar attenuation gradient could indicate early lung diseases. However, its significance has not been determined in detail. We aimed to quantify the anteroposterior intralobar attenuation gradient on volumetric end-inspiratory and end-expiratory high-resolution computed tomography (CT) in patients with emphysema and to correlate the gradient values with pulmonary function. The study population consisted of 21 consecutive patients with emphysema evaluated with volumetric expiratory high-resolution CT and 6 patients with normal high-resolution CT findings. The anteroposterior intralobar attenuation gradient values were quantified on end-inspiratory and end-expiratory sagittal reformations using a lung analysis software program and were correlated with pulmonary function tests results. The intralobar attenuation gradient values in patients with forced expiratory volume in 1 second (FEV1) < or =70% were significantly smaller compared with those in patients with FEV1 >70% in bilateral lower lobes at end-expiration (P = .0061, P = .047, respectively, unpaired t-test). The FEV1 values in patients with attenuation gradient values < or =0.02 were significantly lower than in those with attenuation gradient values >0.02 (right lower lobe: P = .024; left lower lobe: P = .0034; chi-squared test). The intralobar attenuation gradient values in bilateral lower lobes at end-expiration were significantly correlated with FEV1 and FEV1/forced vital capacity (right: P = .031, P = .039, respectively; left: P = .036, P = .030, respectively, Pearson correlation). The quantitative measurement of the anteroposterior intralobar attenuation gradient values of the lung showed that these gradients at end-expiration in both lower lobes correlate with obstructive physiology.

Pulmonary involvement in lifelong non-smoking patients with rheumatoid arthritis and ankylosing spondylitis without respiratory symptoms

Pulmonary involvement seen in rheumatoid arthritis (RA) and ankylosing spondylitis (AS) has been detected increasingly by using highly sensitive diagnostic techniques such as high-resolution computed tomography (HRCT). However, HRCT findings in healthy controls and the effects of smoking and drugs have not been well studied. The aim of this controlled study was to evaluate the relationships between disease-specific clinical, laboratory, HRCT and pulmonary function test (PFT) findings in 20 RA patients using methotrexate (MTX) and 20 AS patients using sulphasalazine who were non-smokers and exhibited asymptomatic respiratory signs. For this purpose, a total of 60 persons (40 patients and 20 healthy controls) were included in this study. A restrictive pattern on PFT was detected in four patients (20%) with AS, one patient with RA and one control (p<0.05). Fourteen patients (70%) with RA and ten patients (50%) with AS had positive HRCT findings. Only one patient (5%) in the control group had abnormal HRCT findings (p<0.05). Interstitial lung disease (ILD) was the most frequently seen HRCT finding in both the RA (35%) and AS (20%) groups. The chest expansion measurement, the score of the visual analogue scale (VAS) for pain and C-reactive protein (CRP) levels were statistically significantly better in patients with AS having normal HRCT than in those with abnormal findings (p<0.05). There was no correlation detected between HRCT and duration of disease, disease activity markers, functional indexes and PFT in patients with RA and AS. HRCT is a sensitive tool in detecting ILD in patients with RA and AS with no signs and symptoms of pulmonary involvement and may be an integral part of such work-up. However, future prospective studies are needed to better determine if HRCT is in fact a predictor of subsequent MTX toxicity.

Avaliação da tomografia de alta resolução versus radiografia de tórax na doença intersticial pulmonar na esclerose sistêmica

OBJETIVO: Avaliar a acurácia da tomografia de alta resolução (TCAR) do tórax em relação à radiografia simples (RX) do tórax no diagnóstico de doença intersticial pulmonar relacionada à esclerose sistêmica (ES). MATERIAIS E MÉTODOS: Foram realizados TCAR e RX de tórax em póstero-anterior e perfil em 34 pacientes com diagnóstico de ES, segundo critérios do Colégio Americano de Reumatologia, e feita comparação entre as prevalências dos achados radiológicos sugestivos de doença intersticial pulmonar encontradas com estes dois métodos de imagem. RESULTADOS: Foram observadas alterações em 31 (91%) das TCAR, enquanto 16 (47%) dos RX de tórax se apresentavam alterados. Os achados mais freqüentes à TCAR foram: linhas septais (74%), faveolamento (56%) e bandas parenquimatosas (26%), localizados predominantemente nas bases pulmonares. Os RX de tórax demonstraram áreas de infiltrado reticular em 32% dos casos e distorção parenquimatosa em 12% dos pacientes. Em 18 (53%) pacientes com RX de tórax normal a TCAR revelou espessamento septal em 55%, vidro fosco em 44%, faveolamento em 38,5% e cistos em 33%. CONCLUSÃO: A TCAR é mais sensível que o RX de tórax para a investigação de envolvimento intersticial pulmonar inicial em pacientes com ES, justificando, em casos incipientes, tratamento com terapia imunossupressora.

High-Resolution Computed Tomography Is Useful for Early Diagnosis of Severe Acute Respiratory Syndrome–Associated Coronavirus Pneumonia in Patients with Normal Chest Radiographs

We investigated the usefulness of high-resolution computed tomography (HRCT) in early detection of severe acute respiratory syndrome (SARS)-associated coronavirus pneumonia and analyzed HRCT findings associated with potentially more severe disease. All patients with suspected SARS and normal chest radiographs on admission within the study period were subjected to HRCT examination. The clinical, radiologic, and laboratory data of patients who were confirmed to have SARS-associated coronavirus infection by a positive nasopharyngeal aspirate, stool or urine reverse transcription-polymerase chain reaction (RT-PCR) and/or serological testing were prospectively followed up and analyzed. Characteristics of patients admitted to the intensive care unit (ICU) and those that were not were compared. Among 47 suspected SARS patients with normal chest radiographs, 27 had SARS-associated coronavirus infection confirmed by RT-PCR and/or positive serological testing. Twenty-five of the 27 (93%) patients had HRCT changes compatible with atypical pneumonia, and all 25 patients developed SARS with progressive clinical deterioration. Ten (40%) had unifocal diseases, and 15 had multifocal diseases (60%). Ten (40%) patients had the diseases confined to 1 single lung in the first HRCT, and both lungs were involved at initial presentation in 15 (60%) patients. Concerning the overall extent of the disease at initial presentation, 3 (12%) patients had disease process in all lobes, and the disease was confined to 1 single lobe in 10 (40%) patients. The disease process was mainly peripheral in location (96%), and the lower lobes were more commonly involved (68% in the left lower lobe and 64% in the right lower lobe). Small parapneumonic effusions occurred in 1 (4%) patient. None of the patients with unifocal lesions or single-lung involvement were admitted to the ICU (P < 0.05) (in both comparisons). Subsequent follow-up of the 2 (7%) patients with normal HRCT on admission showed that they were having nonpneumonic SARS-associated coronavirus infection only and were eventually denotified from having SARS. HRCT is useful for early diagnosis of SARS-associated coronavirus pneumonia in patients with normal chest radiographs. HRCT findings in these patients predict potentially severe disease.

Preoperative High Resolution CT and MR Imaging in Cochlear Implantation

Introduction: Accurate preoperative imaging of the temporal bone in patients receiving cochlear implants is important. High resolution computed tomography (HRCT) and magnetic resonance (MR) imaging are the 2 preoperative imaging modalities that provide critical information on abnormalities of the otic capsule, pneumatisation of the mastoid, middle ear abnormalities, cochlear ducts patency and presence of cochlear nerve. Materials and Methods: The HRCT and MR imaging in 46 cochlear implant patients in our department were reviewed. Results: Majority of our patients [34 patients (73.9%)] showed normal HRCT of the temporal bone; 5 (10.9%) patients had labyrinthitis ossificans, 2 (4.3%) had Mondini’s abnormality and 2 (4.3%) had middle ear effusion. One patient each had high jugular bulb, hypoplasia of the internal auditory canal and single cochlear cavity, respectively. Conclusion: The above findings contribute significantly to our surgical decisions regarding candidacy for surgery, side selection and surgical technique in cochlear implantation.

Lung findings on high resolution CT in early ankylosing spondylitis

Objective: Ankylosing spondylitis (AS) is a chronic inflammatory disease mainly affecting the axial skeleton and pulmonary involvement is a well known feature of the disease. The aim of this study was to investigate the pulmonary high resolution computed tomography (HRCT) findings of patients with early AS. The relationship between pulmonary function tests (PFT) and HRCT findings was also determined. Subjects and methods: Twenty-eight patients with AS (mean age 30.8±7.4 and disease duration 7.0±2.6) were included in the study. Patients with a disease duration of >10 years or had other pulmonary diseases were excluded. All patients underwent plain chest radiography (posteroanterior and lateral views), thoracic HRCT and PFT. Results: All chest radiographs were normal and HRCT revealed abnormalities in 18 patients. The most common abnormalities seen on HRCT were mosaic pattern (ten of 28), subpleural nodule (seven of 28) and parenchymal bands (five of 28). Seven of ten patients with mosaic pattern revealed air trapping areas on end expiratory scans. Twelve patients had abnormal PFT and all had restrictive type of involvement. Ten of these 12 patients had abnormal HRCT and the remaining two patients had normal HRCT. On the other hand, eight patients with normal PFT had abnormalities on HRCT. Conclusion: Patients with early AS frequently have abnormalities on HRCT, even though they have normal PFT and chest X-ray. Small airway involvement was found as frequent as interstitial lung disease in early AS.

Late abnormal findings on high-resolution computed tomography after Mycoplasma pneumonia.

The clinical course of Mycoplasma pneumonia is typically mild and self-limited. There are, however, several case reports of severe complication following this illness with considerable morbidity and mortality. This study was conducted to investigate, using high-resolution computed tomography (HRCT), the long-term pulmonary structural abnormalities after Mycoplasma pneumonia and to identify risk factors (chest radiograph findings, antibody titers, and host factors) that might increase the likelihood of developing the sequelae. Thirty-eight children requiring hospitalization attributable to Mycoplasma pneumonia were recruited by the retrospective examination of hospital records. They underwent HRCT after an interval of 1.0 to 2. 2 years. A control group of 17 children with the history of Mycoplasma upper respiratory infection was also studied after a similar interval. Abnormal HRCT findings were present in 37% (14/38) of the pneumonia group, compared with 12% (2/17) of the control group. The abnormalities in the pneumonia group, which appeared alone or in combination, included mosaic perfusion (n = 12), bronchiectasis (n = 8), bronchial wall thickening (n = 4), decreased vascularity (n = 1), and air trapping on expiratory scan (9 of 29 tested). The area affected by these abnormalities, usually involving 2 or more lobes, corresponded in all cases to the location of the infiltrate on chest radiograph at the time of pneumonia. Between subjects with abnormal HRCT (n = 14) and normal HRCT (n = 24) in the pneumonia group, significant differences were observed in age at the time of pneumonia (mean +/- standard deviation: 5.3 +/- 2. 0 years vs 7.7 +/- 3.4 years) and peak antimycoplasma antibody titer (geometric mean [range of 1 standard deviation]; 1:7943 [3126-19 953] vs 1:3093 [832-11 482]). We conclude that a considerable proportion of children with history of Mycoplasma pneumonia have abnormal findings on HRCT, suggestive of small airway obstruction and that younger age and higher antibody titer at the time of pneumonia may be risk factors for these sequelae.

Cigarette smoke inhalation and lung damage in smoking volunteers.

Cigarette smoking is the dominant risk factor for chronic obstructive pulmonary disease (COPD) but only 10-15% of smokers develop the condition. Risk does not relate closely to cumulative cigarette consumption, perhaps because smokers vary in the degree and depth of smoke inhalation. This study examined the role of smoke inhalation in the development of COPD. Eighty current smokers and 20 lifetime nonsmoking volunteers (aged 35-65 yrs) were recruited. Lung function variables were measured and high-resolution computed tomography (HRCT) scans performed. Smoke inhalation was assessed by CO boost (the increment of expired carbon monoxide 5 min after smoking a cigarette) and serum cotinine. Mean CO boost was 6.3 parts per million (ppm) in smokers with low CO transfer coefficients (KCO) and 2.9 ppm in those with normal KCO (p=0.006); 7.2 ppm in smokers with both HRCT-defined emphysema and a low KCO and 2.6 ppm in those with neither abnormality (p=0.002); 4.5 ppm in smokers with HRCT-defined emphysema alone and 2.8 ppm in those without (p=0.08). Mean serum cotinine was 328 ng x mL(-1) in smokers with chronic productive cough and 243 ng x mL(-1) in those without (p=0.005). Lifetime nonsmokers had normal HRCT scans, lung function and serum cotinine. Emphysema is associated with high alveolar smoke exposure as measured by CO boost. Productive coughing is associated with high nicotine uptake, probably from airway smoke particle deposition.

High-Resolution Computed Tomography of Bronchiolitis Obliterans Syndrome after Bone Marrow Transplantation

High-resolution computed tomography (HRCT) has been described to be useful in assessing bronchiolitis obliterans (BO) syndrome in the transplanted lung. Currently, BO syndrome is diagnosed if lung function deterioration shows persistent or progressive irreversible airflow obstruction, with FEV₁ of less than 80% of baseline values, without clinical evidence of infection. The aim of this study is to assess the value of HRCT in evaluating BO syndrome after allogenic bone marrow transplantation (BMT). Fourteen HRCT scans were performed in 6 women and 3 men with moderately severe irreversible airflow obstruction and a clinical diagnosis of BO syndrome after BMT. Two patients had normal HRCT scans. In the remaining 7 patients, 7 of 11 HRCT scans were abnormal, with non-specific findings of bronchial dilatation (1), consolidation (2), hypoattenuated areas (4) and vascular attenuation (4). In comparison with the consistency of positive HRCT findings of BO syndrome in transplanted lungs, HRCT surveillance for BO syndrome in post-BMT patients with clinically established disease is of limited value, unless other pulmonary complications such as opportunistic infections are to be excluded.

Airways involvement in rheumatoid arthritis: clinical, functional, and HRCT findings.

The aim of the present study was to assess the prevalence and characteristics of airways involvement in rheumatoid arthritis (RA) patients in the absence of interstitial lung disease. We prospectively evaluated, with high-resolution computed tomography (HRCT) and pulmonary function tests (PFTs), 50 patients with RA (nine males and 41 females; mean age: 57.8 yr), including 39 nonsmokers and 11 smokers (mean cigarette consumption: 15.3 pack-yr) without radiographic evidence of RA-related lung changes. PFTs demonstrated airway obstruction (i.e., reduced FEV1/VC) in nine patients (18%) and small airways disease (SAD) (i.e., decreased FEF(25-75), defined as exceeding the predicted value by 1.64 residual SD [RSD] or more, and/or an increased phase III slope > 2 SD by single breath nitrogen washout) in four patients (8%). HRCT demonstrated bronchial and/or lung abnormalities in 35 cases (70%), consisting of air trapping (n = 16; 32%), cylindral bronchiectasis (n = 15; 30%), mild heterogeneity in lung attenuation (n = 10; 20%), and/or centrilobular areas of high attenuation (n = 3; 6%). Airway obstruction and SAD were correlated with the presence of bronchiectasis and bronchial-wall thickening (p = 0.003), and with bronchial infection (p = 0.01), but were unrelated to rheumatologic data. FEF(25-75) was reduced and the slope of phase III was increased in patients with airway changes on HRCT scans, whereas no PFT abnormalities were found in 13 of 15 patients with normal HRCT scans. HRCT depicted features of SAD in 20 of the 33 patients with normal PFTs. HRCT findings were unrelated to rheumatologic data. A high prevalence of airway abnormalities as assessed with HRCT and/or PFTs was observed in our RA population. HRCT appears to be more sensitive than PFTs for detecting small airways disease.

Cigarette smoking: CT and pathologic findings of associated pulmonary diseases.

The health risks associated with cigarette smoking are well known. Cigarette smoking is the most important causative factor in the development of bronchogenic carcinoma. Pulmonary diseases such as chronic bronchitis, centrilobular and panacinar emphysema, respiratory bronchiolitis-associated interstitial lung disease (RB-ILD), and pulmonary Langerhans cell histiocytosis are also related to cigarette smoking. In adenocarcinoma and squamous cell carcinoma, the most common manifestation at computed tomography (CT) is a solitary pulmonary nodule; in small cell carcinoma, hilar and mediastinal adenopathy secondary to metastases; and in large cell carcinoma, a mass with central necrosis or cavitation in the lung periphery. For chronic bronchitis, the most common CT finding is bronchial wall thickening, but this finding is nonspecific. Emphysema, both centrilobular and panacinar associated with alpha-1-antitrypsin deficiency, usually manifests as areas of decreased attenuation and may involve bullous changes. However, centrilobular emphysema more commonly involves the upper lungs, whereas panacinar emphysema more commonly involves the lower lungs. Most patients with RB-ILD have normal high-resolution CT scans; however, abnormalities may be present, the most common of which are areas of ground-glass attenuation. CT appearance of pulmonary Langerhans cell histiocytosis varies depending on the disease stage: In the early stage, typical CT findings include multiple nodules, usually accompanied by cystic spaces with thin, well-defined walls. As the disease progresses, the cystic spaces become more numerous and the number of nodules decreases.

Differentiation of the ILO Boundary Chest Roentgenograph (0/1 to 1/0) in Asbestosis by High-Resolution Computed Tomography Scan, Alveolitis, and Respiratory Impairment

High-resolution computed tomography (HRCT) scans have been advocated as providing greater sensitivity in detecting parenchymal opacities in asbestos-exposed individuals, especially in the presence of pleural fibrosis, and having excellent inter- and intraobserver reader interpretation. We compared the 1980 International Labor Organization (ILO) International Classification of the Radiographs of the Pneumoconioses for asbestosis with the high-resolution CT scan using a grid scoring system to better differentiate normal versus abnormal in the ILO boundary 0/1 to 1/0 chest roentgenograph. We studied 37 asbestos-exposed individuals using the ILO classification, HRCT grid scores, respiratory symptom questionnaires, pulmonary function tests, and bronchoalveolar lavage. We used Pearson correlation coefficients to evaluate the linear relationship between outcome variables and each roentgenographic method. The normal HRCT scan proved to be an excellent predictor of "normality," with pulmonary function values close to 100% for forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), total lung capacity (TLC), and carbon monoxide diffusing capacity (DLCO) and no increase in BAL inflammatory cells. Concordant HRCT/ILO abnormalities were associated with reduced FEV1/FVC ratio, reduced diffusing capacity, and alveolitis consistent with a definition of asbestosis. In our study, the ILO classification and HRCT grid scores were both excellent modalities for the assessment of asbestosis and its association with impaired physiology and alveolitis, with their combined use providing statistical associations with alveolitis and reduced diffusing capacity.

High resolution computed tomography for the evaluation of lung involvement in 101 patients with scleroderma.

The aim of the study was to investigate the pulmonary parenchymal abnormalities by high resolution computed tomography (HRCT) in patients with various forms of scleroderma. Three scans were performed sequentially in all cases: one at the level of aortic arch, one at the tracheal carina and one 1-2 cm above the diaphragm. Seventy cases with limited, 21 patients with diffuse cutaneous systemic sclerosis and 10 cases with circumscribed scleroderma were investigated. The 21 patients with diffuse scleroderma included three normal HRCT scan (14%), three with ground glass attenuation (14%), one with ground glass attenuation with fibrosis, three with fibrosis (14%), six with subpleural and five with diffuse honeycombing. The majority of cases with extensive honeycombing of the lungs had anti-Sc! 70 autoantibody which was the characteristic antibody of the diffuse scleroderma subset. The 70 cases with limited cutaneous systemic sclerosis were characterized by normal HRCT (43%), ground glass opacity with or without fibrosis (18.6%), whereas fibrosis was detected in 22.9%, subpleural or diffuse honeycombing in 15.7% of the patients. Six of the ten cases with circumscribed scleroderma also showed a fibrosis. Cases with diffuse scleroderma are characterized by the presence of advanced fibrosis, whereas the extent of fibrosis is far less pronounced in limited scleroderma. Mild fibrosis may also be present in circumscribed scleroderma forms.

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.