High-resolution CT Findings In Patients Research Articles

Acute Q fever pneumonia: high-resolution computed tomographic findings in six patients.

We analyzed high-resolution CT (HRCT) findings from six male patients (mean age, 22.6 years) with confirmed diagnoses of acute Q fever. Two chest radiologists analyzed the images and reached decisions by consensus. All patients presented fever, myalgia, prostation, headache, and dry cough. They also had common epidemiologic factors (recent travel for military service, where they had contact with sheep and capybara). Diagnoses were confirmed by the detection of C. burnetii DNA in clinical samples by polymerase chain reaction. The predominant HRCT findings were areas of consolidation (100%) and nodules (66.6%) with halos of ground-glass opacity, predominantly with segmental and peripheral distributions. Lesions affected all lobes, and predominated in the left upper and lower lobes. Involvement of more than one lobe was observed in four patients. No pleural effusion or lymph node enlargement was found. The predominant HRCT findings in patients with acute Q fever pneumonia were bilateral, peripheral areas of consolidation and nodules with irregular contours and halos of ground-glass opacity. Acute Q fever should be included in the differential diagnosis of lesions with the halo sign on HRCT.

Serial evaluation of high-resolution CT findings in patients with pneumonia in novel swine-origin influenza A (H1N1) virus infection

The purpose of our study was to review the changes in the serial high-resolution CT (HRCT) findings from patients with novel swine-origin influenza A (H1N1) virus (S-OIV) infection. HRCT findings of 70 patients with presumed or laboratory-confirmed novel S-OIV infection were reviewed. The pattern (consolidation, ground glass, fibrosis and air trapping), distribution and extent of abnormality of the lesions on the HRCT were evaluated at different time points. To assess changes that occurred over time, the CT scans in 56 patients were examined in sequence. The most common CT findings in patients with S-OIV infection are ground-glass opacities with or without consolidation at the first week. The abnormalities peaked at the second week and resolved after that time, which resulted in substantial reduced residual disease at 4 weeks or later. The development of fibrosis was noted in the first week and peaked at the third week of illness (34.7%), then decreased slowly after that time. The mean time of air trapping being noted after the onset of symptoms was 55.5 ± 20.6 days. Comparing the findings of initial CT, most results (96.4%) of follow-up chest CT findings showed improvement (p<0.01). The abnormalities of ground-glass opacities and/or consolidation on initial CT scans tended to resolve to fibrosis, which then resolved completely or displayed substantially reduced residual disease. HRCT may show more changes in disease progression and play an important role in the evaluation of severe S-OIV.

High-resolution CT Findings in Patients With Pulmonary Tuberculosis

There are data about the relationship between morphologic findings on high-resolution computed tomography (HRCT) and the number of acid-fast bacilli (AFB) on sputum smears in patients with pulmonary tuberculosis (PTB). It was also shown that existence of cavities and airspace consolidation might be related to smear positivity in PTB patients. However, there is no study suggesting a relationship between AFB on sputum smears and radiologic extent of disease based on HRCT findings. In this study, we investigated a relationship between the degree of smear positivity and radiologic extent of disease based on HRCT findings and, the degree of smear positivity and different pulmonary parenchymal changes on HRCTs of the PTB patients. Sixty-one male patients with PTB (mean age: 22+/-3.2) were included into the study. HRCT images were assessed for patterns, distribution, and profusion of pulmonary abnormalities. Dividing the lungs into 3 zones, profusion of abnormalities was assessed. A profusion score was given. Patients were divided as smear positive and smear negative and compared for the scores of HRCT findings. Smear-positive patients were divided into 4 groups as per grading of the sputum AFB smear: group I (sputum 1+), group II (sputum 2+), group III (sputum 3+), and group IV (sputum 4+). Correlations were investigated between the degree of smear positivity and the scores of HRCT findings. A significant correlation between radiologic extent of the disease based on HRCT and the degree of smear positivity was found (r=0.63, P=0.0001). There were also significant correlations between the degree of smear positivity and the scores of different HRCT findings. Nodule, cavity, and bronchial lesions are the most important contributors of the predictive properties of the total score. There was significant differences for the scores of HRCT findings between smear-positive and smear-negative patients. Our study suggests that radiologic extent of disease based on HRCT findings in patients with PTB correlated with the degree of smear positivity. Different HRCT findings such as nodule, cavitation, ground-glass opacity, consolidation, and bronchial lesion are significantly associated with smear-positive PTB. Particularly, nodules, cavities, and bronchial lesions might be predictors of smear positivity in patients with PTB. This study also suggests that the thickness of cavity wall and the distance of cavity from central airways might be related to the degree of smear positivity.

Pulmonary Infections After Bone Marrow Transplantation: High-Resolution CT Findings in 111 Patients

The purpose of this study was to review the high-resolution CT findings in patients with pulmonary infection after bone marrow transplantation and to determine distinguishing features among the various types of infection. This study included 111 consecutive bone marrow transplant recipients who had documented pulmonary infection, high-resolution CT of the chest performed within 24 hr of the beginning of symptoms, and proven diagnosis within 1 week of the onset of symptoms. Two radiologists analyzed the CT scans and reached final decisions regarding the findings by consensus. Statistical analysis was performed using the Fisher's exact test and multivariate analysis; a p value of less than 0.05 was considered statistically significant. The pulmonary infections were due to viruses (n = 57), bacteria (n = 26), fungi (n = 21), and protozoa (n = 1). Six patients had more than one organism responsible for the infection. Nodules that were 1 cm or more in diameter were seen in 13 (62%) of 21 patients with fungal pneumonia, five (19%) of 26 patients with bacterial pneumonia (p = 0.0059), three (10%) of 30 with respiratory syncytial virus (RSV) pneumonia (p = 0.0001), and three (14%) of 22 with cytomegalovirus pneumonia (p = 0.0016). The halo sign was present in 10 of 21 patients with fungal pneumonia, two of 26 with bacterial pneumonia (p = 0.0026), three of 30 with RSV pneumonia (p = 0.0036), and one of 22 with cytomegalovirus pneumonia (p = 0.0015). There was no statistically significant difference in the prevalence of the other CT patterns including small nodules, ground-glass attenuation, and air-space consolidation among viral, bacterial, and fungal infections (all p > 0.05). The presence of large nodules and visualization of the halo sign are most suggestive of fungal infection. Other high-resolution CT patterns are not helpful in distinguishing among the various types of infection seen in bone marrow transplant recipients.

High-Resolution CT Findings in Patients With Near-Fatal Asthma: Comparison of Patients With Mild-to-Severe Asthma and Normal Control Subjects and Changes in Airway Abnormalities Following Steroid Treatment

Study objectives: Extensive airway inflammation and excessive mucus production are implicated in deaths from asthma. High-resolution CT (HRCT) can be used to image both large and small airway abnormalities in asthmatics. The aims of this study were to clarify the distinction of HRCT features between near-fatal asthma (NFA) and non-NFA, and to evaluate serial follow-up HRCT scans of patients with NFA. Patients and design: Abnormalities of the large airway (bronchial wall thickness) and small airways (prominence of centrilobular structures and air trapping) were measured semiquantitatively on HRCT scans of 24 non-NFA, 16 NFA, and 16 control subjects. In addition, these abnormalities were reevaluated after intensive and relatively long-term (> 6 months) treatment with inhaled corticosteroids. Results: Prominence of centrilobular structures was observed in 36% of mild asthma cases, in 70% of moderate-to-severe asthma cases, and in 100% of NFA cases. Prominence of centrilobular structures, but neither bronchial wall thickness nor the area of air trapping, was significantly increased in NFA, as compared with mild or moderate-to-severe asthma (p < 0.05). In the seven non-NFA and five NFA patients who underwent follow-up HRCT scans, only bronchial wall thickness was decreased significantly in the NFA cases (p < 0.05), while bronchial wall thickness and the prominence of centrilobular structures were significantly decreased in the non-NFA cases. These small airway abnormalities were partially reversible in the both groups. Residual prominence of centrilobular structures after long-term inhaled corticosteroid treatment was significantly higher in NFA than non-NFA patients. Conclusions: The results of our study indicate that extensive small airway abnormalities may be associated with NFA, and that these abnormalities are partially reversible after the successful control of asthma symptoms. Extensive airway inflammation and excessive mucus production are implicated in deaths from asthma. High-resolution CT (HRCT) can be used to image both large and small airway abnormalities in asthmatics. The aims of this study were to clarify the distinction of HRCT features between near-fatal asthma (NFA) and non-NFA, and to evaluate serial follow-up HRCT scans of patients with NFA. Abnormalities of the large airway (bronchial wall thickness) and small airways (prominence of centrilobular structures and air trapping) were measured semiquantitatively on HRCT scans of 24 non-NFA, 16 NFA, and 16 control subjects. In addition, these abnormalities were reevaluated after intensive and relatively long-term (> 6 months) treatment with inhaled corticosteroids. Prominence of centrilobular structures was observed in 36% of mild asthma cases, in 70% of moderate-to-severe asthma cases, and in 100% of NFA cases. Prominence of centrilobular structures, but neither bronchial wall thickness nor the area of air trapping, was significantly increased in NFA, as compared with mild or moderate-to-severe asthma (p < 0.05). In the seven non-NFA and five NFA patients who underwent follow-up HRCT scans, only bronchial wall thickness was decreased significantly in the NFA cases (p < 0.05), while bronchial wall thickness and the prominence of centrilobular structures were significantly decreased in the non-NFA cases. These small airway abnormalities were partially reversible in the both groups. Residual prominence of centrilobular structures after long-term inhaled corticosteroid treatment was significantly higher in NFA than non-NFA patients. The results of our study indicate that extensive small airway abnormalities may be associated with NFA, and that these abnormalities are partially reversible after the successful control of asthma symptoms.

Cytomegalovirus pneumonia after bone marrow transplantation: high resolution CT findings.

Cytomegalovirus (CMV) pneumonia is one of the most common pulmonary complications after bone marrow transplantation (BMT). We describe the high resolution CT (HRCT) findings of 13 patients with CMV pneumonia diagnosed after allogenic BMT. The study included 13 consecutive patients who developed CMV pneumonia after BMT and who had HRCT of the chest performed within 24 h of the onset of symptoms. HRCT scans were reviewed by two radiologists who assessed pattern and distribution of findings. There were nine male and four female patients, ranging from 9 years to 56 years of age (mean age 33 years). BMT was performed for treatment of chronic myelogenous leukaemia (54%), severe aplastic anaemia (23%), acute myelogenous leukaemia (15%) and Fanconi's anaemia (8%). The time elapsed until diagnosis ranged from +18 days to +405 days (median of 54 days, mean +81.6 days). The predominant patterns of abnormality on HRCT scans were ground-glass opacities (69%), small centrilobular nodules (69%) and air-space opacities (54%). The abnormalities were distributed in the central and peripheral zones of the lungs in six cases, only in the periphery in four cases, and only in the central zone in three cases. In all cases the lung lesions were bilateral, and asymmetry was observed in seven cases. The authors conclude that the most common HRCT findings in patients with CMV pneumonia after BMT consist of bilateral asymmetric ground-glass, air-space opacities and small centrilobular nodules.

High-resolution CT findings of respiratory syncytial virus pneumonia after bone marrow transplantation.

The aim of this study was to describe the high-resolution CT findings of respiratory syncytial virus pneumonia in 20 patients who had undergone allogeneic bone marrow transplantation. The study included 20 consecutive patients who developed respiratory syncytial virus pneumonia after bone marrow transplantation and who had high-resolution CT of the chest performed within 24 hr after the onset of symptoms. The CT scans were reviewed by two chest radiologists who assessed the pattern and distribution of findings. Bone marrow transplantation was performed on 12 male and eight female patients ranging from 3 to 48 years old (mean age, 25 years) for treatment of various forms of leukemia (n = 12), severe aplastic anemia (n = 6), Fanconi's syndrome (n = 1), and paroxysmal nocturnal hemoglobinuria (n = 1). Sixteen patients (80%) had abnormal CT findings. The predominant patterns of abnormality on high-resolution CT scans were small centrilobular nodules (10/20, 50%), air-space consolidation (7/20, 35%), ground-glass opacities (6/20, 30%), and bronchial wall thickening (6/20, 30%). The abnormalities were distributed in the central and peripheral areas of the lungs in nine cases, only in the periphery in five cases, and only in the central regions in two cases. The abnormalities were bilateral and asymmetric in distribution in 13 patients, bilateral and symmetric in two patients, and unilateral in one patient. The most common high-resolution CT findings in patients with respiratory syncytial virus pneumonia after bone marrow transplantation consist of small centrilobular nodules and multifocal areas of consolidation and ground-glass opacities in a bilateral asymmetric distribution.

High-resolution CT findings in patients with severe acute respiratory syndrome: a pattern-based approach.

We retrospectively reviewed high-resolution CT (HRCT) examinations of the lungs performed in 27 confirmed cases of severe acute respiratory syndrome (SARS). The HRCT findings at different phases of the illness were analyzed. A defined pattern of HRCT findings is observed in different phases of SARS, which is characterized by focal ground-glass and crazy paving patterns in a scattered distribution at presentation, followed by development of interstitial thickening, consolidation, pleural reaction, and scarring. Spontaneous pneumomediastinum is a distinct complication during the course of the illness.

Hermansky-Pudlak syndrome: radiography and CT of the chest compared with pulmonary function tests and genetic studies.

The objective of our study was to describe the chest radiographic and high-resolution CT findings in patients with Hermansky-Pudlak syndrome and to correlate the radiologic findings with age, causative gene, and pulmonary function. Sixty-seven patients with Hermansky-Pudlak syndrome underwent high-resolution CT of the chest. A scoring system based on the extent of pulmonary involvement and specific high-resolution CT findings was used, and the findings were compared with patient age and the results of pulmonary function and genetic studies. Fifty-eight (87%) of the 67 patients also underwent chest radiography. These radiographs were compared with the high-resolution CT scans. High-resolution CT was more sensitive than chest radiography in evaluating the extent of pulmonary disease in patients with Hermansky-Pudlak syndrome. All patients with mild findings on high-resolution CT scans had normal findings on chest radiographs. Common chest radiographic findings included reticulonodular interstitial pattern, perihilar fibrosis, and pleural thickening. High-resolution CT showed septal thickening, ground-glass opacities, and peribronchovascular thickening. For patients with Hermansky-Pudlak syndrome who were 30 years old or younger, high-resolution CT findings were usually minimal. Among patients who were older than 30 years, the 34 patients with HPS1 mutations had a score of 1.38+/-0.18 (mean+/-standard error of the mean) on high-resolution CT. This score is significantly greater than the score for the 11 patients without HPS1 mutations (0.36 +/- 0.15) (p < 0.001). The score based on high-resolution CT findings inversely correlated with percentage of forced vital capacity and was useful in defining the progression of interstitial disease. High-resolution CT provides a good radiologic monitor of disease status and progression in patients with Hermansky-Pudlak syndrome and correlates well with patient age, extent of pulmonary dysfunction, and genetic findings.

Pulmonary Function and High-Resolution CT Findings in Patients With an Inherited Form of Pulmonary Fibrosis, Hermansky-Pudlak Syndrome, Due to Mutations in HPS-1

To describe and correlate pulmonary function and high-resolution CT (HRCT) scan scores in individuals with a high risk for development of pulmonary fibrosis, ie, Hermansky-Pudlak syndrome (HPS) patients with mutations in the HPS-1 gene. Cross-sectional analysis of consecutive, eligible patients. Thirty-eight HPS inpatients at the National Institutes of Health Clinical Center with HPS-1 mutations. Thirty-seven patients were Puerto Rican and exhibited the typical 16-base pair (bp) duplication in exon 15 of HPS-1. One non-Puerto Rican was homozygous for a different mutation (intervening sequence 17 -2 A-->C) previously reported in the HPS-1 gene; he died at age 35 of pulmonary insufficiency. For the 23 patients who had pulmonary symptoms, the mean age of onset was 35 years. For all 38 patients (mean age, 37 +/- 2 years), the mean FVC was 71% of predicted; the mean FEV(1), 76%; mean total lung capacity (TLC), 72%; mean vital capacity (VC), 68%; and mean diffusing capacity of the lung for carbon monoxide (DLCO), 72%. When patients were grouped according to the extent of their reduction in FVC, the other four pulmonary function parameters followed the FVC. Seventeen patients had abnormal chest radiographs, and 31 (82%) had abnormal HRCT scans of the chest, for which a scoring system of 0 (normal) to 3 (severe fibrosis) is presented. The mean +/- SEM HRCT score for 38 patients was 1.30 +/- 0.17. HRCT scores correlated inversely with FVC and DLCO. Mutations in the HPS-1 gene, whether or not they involve the typical 16-bp duplication seen in Puerto Rican patients, are associated with fatal pulmonary fibrosis. In affected patients, the FVC, FEV(1), TLC, VC, and DLCO fall in concert, and this functional deficit correlates with HRCT scan evidence of progression of interstitial lung disease.

Plain radiographs and thoracic high-resolution CT in patients with ankylosing spondylitis.

The aims of this study were to identify the spectrum of abnormalities seen on high-resolution CT in patients with ankylosing spondylitis and to compare our findings with reports of plain film pulmonary manifestations of the disease. We prospectively studied 26 patients with documented ankylosing spondylitis. All patients underwent plain chest radiography (posteroanterior and lateral views), thoracic helical CT, high-resolution CT, and pulmonary function tests. High-resolution CT revealed abnormalities in 18 patients (69%), whereas plain chest radiography revealed abnormalities in four patients (15%). The most common abnormalities seen on CT were interstitial lung disease (ILD) (n = 4), bronchial wall thickening and bronchiectasis (n = 6), paraseptal emphysema (n = 3), mediastinal lymphadenopathy (n = 3), tracheal dilatation (n = 2), and apical fibrosis (n = 2). This study, which describes high-resolution CT findings in patients with ankylosing spondylitis, reveals a spectrum of abnormalities unlike those described in previous reports in which researchers used plain chest radiographs as the sole imaging technique. In addition to apical fibrosis, high-resolution CT revealed nonapical ILD, bronchiectasis, paraseptal emphysema, and tracheobronchomegaly. Of these new findings, we believe that identification of ILD is the most important. We suggest that nonapical ILD should be actively sought as an explanation for pulmonary symptoms developing in patients with ankylosing spondylitis. High-resolution CT should form an integral part of such workup.

Specificity of high-resolution CT findings in pulmonary asbestosis: do patients scanned for other indications have similar findings?

High-resolution CT findings in patients with asbestosis include subpleural curvilinear densities, subpleural density in dependent portions of the lung, parenchymal bands, thickened septal lines, and honeycomb lung. Our objective was to examine the prevalence of these CT findings in a random group of patients scanned for a variety of clinical reasons not specifically related to occupational exposure. One hundred sixty-eight CT studies of the thorax were performed at six levels in 168 patients examined for a variety of clinical indications. The scans were evaluated by two radiologists for the presence of subpleural curvilinear densities, subpleural density in dependent locations, parenchymal bands, thickened septal lines, and honeycomb lung. CT scans of 11 patients showed pleural plaques suggesting previous exposure to asbestos. Among the 157 studies showing no evidence of pleural plaques, CT scans showed subpleural curvilinear densities in dependent areas in 32 (20%); subpleural curvilinear densities in nondependent areas in 19 (12%); parenchymal bands in 47 (30%); thickened septal lines in dependent areas in 93 (59%), and septal lines in nondependent areas in 67 (43%); subpleural density in dependent areas in 66 (42%); and honeycomb lung in five (3%). Subpleural curvilinear densities, subpleural density in dependent locations, parenchymal bands, and thickened septal lines occur as isolated and as combined CT findings in patients with a variety of underlying diseases or conditions unrelated to asbestosis and by themselves are nonspecific findings. Their occurrence, even in patients with CT evidence of pleural plaques, does not necessarily indicate the presence of asbestosis.