Search

Background/Objective \ud Patients classified as interstitial pneumonia with autoimmune features (IPAF) have interstitial lung disease (ILD) and features of autoimmunity but do not fulfill criteria for connective tissue diseases (CTDs). Our goal was to identify patients classifiable as IPAF, CTD-ILD, and idiopathic pulmonary fibrosis (IPF) from a preexisting pulmonary cohort and evaluate the prognosis of patients with IPAF.\ud \ud Methods \ud We reviewed the medical records of 456 patients from a single-center pulmonary ILD cohort whose diagnoses were previously established by a multidisciplinary panel that did not include rheumatologists. We reclassified patients as IPAF, CTD-ILD, or IPF. We compared transplant-free survival using Kaplan-Meier methods and identified prognostic factors using Cox models.\ud \ud Results \ud We identified 60 patients with IPAF, 113 with CTD-ILD, and 126 with IPF. Transplant-free survival of IPAF was not statistically significantly different from that of CTD-ILD or IPF. Among IPAF patients, male sex (hazard ratio, 4.58 [1.77–11.87]) was independently associated with worse transplant-free survival. During follow-up, only 10% of IPAF patients were diagnosed with CTD-ILD, most commonly antisynthetase syndrome.\ud \ud Conclusion \ud Despite similar clinical characteristics, most patients with IPAF did not progress to CTD-ILD; those who did often developed antisynthetase syndrome, highlighting the critical importance of comprehensive myositis autoantibody testing in this population. As in other types of ILD, male sex may portend a worse prognosis in IPAF. The routine engagement of rheumatologists in the multidisciplinary evaluation of ILD will help ensure the accurate classification of these patients and help clarify prognostic factors.

Diagnosis of diffuse parenchymal lung diseases (DPLD) on high resolution CT (HRCT) is difficult for non-expert radiologists due to varied presentation for any single disease and overlap in presentation between diseases.To evaluate whether a pattern-based training algorithm can improve the ability of non-experts to diagnosis of DPLD.Five experts (cardiothoracic-trained radiologists), and 25 non-experts (non-cardiothoracic-trained radiologists, radiology residents, and pulmonologists) were each assigned a semi-random subset of cases from a compiled database of DPLD HRCTs. Each reader was asked to create a top three differential for each case. The non-experts were then given a pattern-based training algorithm for identifying DPLDs. Following training, the non-experts were again asked to create a top three differential for each case that they had previously evaluated. Accuracy between groups was compared using Chi-Square analysis.A total of 400 and 1450 studies were read by experts and non-experts, respectively. Experts correctly placed the diagnosis as the first item on the differential versus having the correct diagnosis as one of their top three diagnoses at an overall rate of 48 and 64.3%, respectively. Pre-training, non-experts achieved a correct diagnosis/top three of 32.5 and 49.7%, respectively. Post-training, non-experts demonstrated a correct diagnosis/top three of 41.2 and 65%, a statistically significant increase (p0.0001). In addition, post training, there was no difference between non-experts and experts in placing the correct diagnosis within their top three differential.The diagnosis of DPLDs by HRCT imaging alone is relatively poor. However, use of a pattern-based teaching algorithm can improve non-expert interpretation and enable non-experts to include the correct diagnosis within their differential diagnoses at a rate comparable to expert cardiothoracic trained radiologists.

Coronavirus(CoV) and human metaneumovirus(hMPV) are worldwide causes of lower respiratory tract infection(LRTI) in adults Chest CT is increasingly used in the diagnosis and management of LRTI Our aims were to compare chest CT features for LRTI due to sporadic CoV with hMPV and correlate chest CT findings with clinical outcomes We retrospectively reviewed records of 61 adults with nucleic acid amplification(NAA) assay positive for CoV and 104 adults positive for hMPV over 33 months at 4 community hospitals in the northeast US A thoracic radiologist reviewed all chest CT images Inclusion criteria included:1 symptoms of acute LRTI, 2 chest CT within 7 days of positive NAA assay, 3 no other pulmonary infection/lung disease that might interfere with chest CT interpretation Ground-glass opacities(GGO) were more frequent (p< 05) with hMPV(47/104,45%) than with sporadic CoV(15/61,25%) Multifocal consolidation was more common (p< 05) with hMPV(31/104,30%) than with sporadic CoV(8/61,13%) LRTI without chest CT findings was more common (p< 05) with sporadic CoV (28/61,46%) than with hMPV (16/104,15%) For hMPV, multifocal consolidation was associated(p< 05) with treatment with assisted ventilation(9/30,30%) For hMPV, no other chest CT finding correlated with any studied outcome(new supplementary oxygen at discharge, discharge to skilled facility, hospital re-admission within 30 days) No chest CT finding correlated with any studied outcome for sporadic CoV With hMPV, healthcare providers should be aware that multifocal consolidation on chest CT often portends treatment with invasive/non-invasive ventilatory support

Human metapneumovirus (hMPV) has increasingly been identified as an important, worldwide cause of lower respiratory tract infections (LRTI) in adults. Our goals were to determine the chest CT imaging features of LRTI due to hMPV and to correlate chest CT imaging features with clinical outcomes. We retrospectively reviewed the medical records and chest CT images of 100 adults collected over 33 months at 4 community hospitals in the northeast US. Chest CT images were reviewed by an experienced thoracic radiologist. Study subjects satisfied 4 criteria: 1. acute lower respiratory tract symptoms, 2. positive reverse-transcriptase polymerase chain reaction (RT-PCR) assay of nasopharyngeal swab for hMPV, 3. chest CT within 7 days of positive RT-PCR assay for hMPV, 4. no other pulmonary infection or other pulmonary disease that might interfere with chest CT interpretation. On review, 16/100 had focal lung consolidation, 30/100 had multifocal lung consolidation, 31/100 had bronchial wall thickening, 44/100 had ground glass opacities and 62/100 had tree-in-bud opacities. Multifocal lung consolidation was associated with increased frequency (9/30, 30%) of treatment with invasive or non-invasive ventilatory support (p

Purpose Human metapneumovirus has been increasingly identified as a cause of lower respiratory tract infection in adults worldwide. The CT imaging features of human metapneumovirus in adults have not been characterized. The purpose of this paper is to determine the imaging features of human metapneumovirus and to compare them with features of other viruses. Methods Two clinicians retrospectively reviewed the medical records of 104 adults with lower respiratory tract infection due to human metapneumovirus at four hospitals in the northeast USA over 32 months. CT images were evaluated by two chest radiologists for airspace consolidation, bronchiectasis, bronchial wall thickening, ground-glass opacities, pleural effusion and tree-in-bud opacities and the dominant imaging pattern. Results for human metapneumovirus were compared with results previously reported for other viruses. Results Human metapneumovirus predominantly caused an airway-centric pattern (71-81/104, 68-77%) of infection characterized by bronchial wall thickening, tree-in-bud opacities, peri-bronchial consolidation and/or peri-bronchial ground-glass opacities. The airway-centric pattern has been previously reported with other paramyxoviridae (parainfluenza virus and respiratory syncytial virus). However, human metapneumovirus was significantly more likely (p = 0.03-0.001) to cause bronchopneumonia (46-55%) than parainfluenza virus (17%) or respiratory syncytial virus (21%). Follow-up CT in 41 (39%) patients with hMPV revealed resolution of findings in 38/41 (91%). Conclusion The paramyxoviridae, including human metapneumovirus, are known to have a propensity to infect ciliated respiratory cells and we have demonstrated this leads to a propensity to cause bronchitis, bronchiolitis and bronchopneumonia on CT scans. Of these, human metapneumovirus is most likely to cause bronchopneumonia. Healthcare providers should consider human metapneumovirus as a cause of pneumonia on chest CT.

Coronavirus(CoV) has been associated with lower respiratory tract infection(LRTI) in adults worldwide. The CoV associated with Sudden Acute Respiratory Syndrone and Middle East Respiratory Syndrone typically cause ground-glass opacities(GGO) and/or consolidation on chest CT. Chest CT features of sporadic CoV(subtypes: HKU1, NL63, OC43, 229E) have not been characterizedc. Our aims were to characterize chest CT features of sporadic CoV and compare these findings with those from other viruses. We retrospectively reviewed the records and chest CT images of 61 adults over 32 months at 4 community hospitals in the northeast US. CT images were reviewed by an experienced thoracic radiologist. Study subjects satisfied 4 criteria: 1) symptoms of acute LRTI, 2) positive polymerase chain reaction assay for CoV, 3)CT within 7 days of positive assay for CoV, 4)no other pulmonary infection or other pulmonary disease that might interfere with CT interpretation. We compared the chest CT features of sporadic CoV with those we previously reported for adenovirus, influenza, human metapneumovirus (hMPV), parainfluenza virus (PIV) and respiratory syncytial virus. On review of CoV cases, 11(18%) had bronchial wall thickening, 15(25%) had GGO, 12(20%) had lung consolidation and 13(21%) had tree-in-bud opacities. Twenty-eight(46%) had no chest CT findings related to acute infection. Sporadic CoV was similar to influenza but different from PIV (p

BACKGROUND:\ud Idiopathic pulmonary fibrosis (IPF), a progressive disease with an unknown pathogenesis, may be due in part to an abnormal response to injurious stimuli by alveolar epithelial cells. Air pollution and particulate inhalation of matter evoke a wide variety of pulmonary and systemic inflammatory diseases. We therefore hypothesized that increased average ambient particulate matter (PM) concentrations would be associated with an accelerated rate of decline in FVC in IPF.\ud \ud METHODS:\ud We identified a cohort of subjects seen at a single university referral center from 2007 to 2013. Average concentrations of particulate matter < 10 and < 2.5 μg/m3 (PM10 and PM2.5, respectively) were assigned to each patient based on geocoded residential addresses. A linear multivariable mixed-effects model determined the association between the rate of decline in FVC and average PM concentration, controlling for baseline FVC at first measurement and other covariates.\ud \ud RESULTS:\ud One hundred thirty-five subjects were included in the final analysis after exclusion of subjects missing repeated spirometry measurements and those for whom exposure data were not available. There was a significant association between PM10 levels and the rate of decline in FVC during the study period, with each μg/m3 increase in PM10 corresponding with an additional 46 cc/y decline in FVC (P = .008).\ud \ud CONCLUSIONS:\ud Ambient air pollution, as measured by average PM10 concentration, is associated with an increase in the rate of decline of FVC in IPF, suggesting a potential mechanistic role for air pollution in the progression of disease.

To identify features of obstructive airway disease on sagittal reconstruction, compare the accuracy of findings to traditional imaging characteristics of COPD, and determine the fraction of additional cases identified using new characteristics. The study was approved by the centre’s Institutional Review Board and is HIPAA compliant. Two hundred sixteen patients with HRCT and spirometry within a 3-month window were included. Four radiologists evaluated each HRCT for traditional characteristics of COPD and new quantitative and qualitative features of obstruction on axial and sagittal reconstructions. Imaging characteristics were assessed for correlation with the spirometric diagnosis of obstructive airway disease. Quantitative and qualitative findings on sagittal reconstruction are highly specific for COPD (specificity >90 %). Features of hyperinflation on sagittal reconstruction are more accurate predictors of obstruction than traditional axial measures, with greater interobserver reliability (hyperinflation left hemidiaphragm: accuracy: 70.08 % ± 2.49 %; kappa: 0.511 versus traditional measures: accuracy: 62.00 % ± 5.38 %; kappa: 0.407). Sagittal reconstruction identified 27-70 % more patients with COPD than traditional axial findings (p

Background\ud Despite the relationship between idiopathic pulmonary fibrosis (IPF) and advancing age, little is known about the epidemiology of interstitial lung disease (ILD) in the elderly. We describe the diagnoses, clinical characteristics, and outcomes of patients who were elderly at the time of ILD diagnosis.\ud \ud Methods\ud Among subjects from a prospective cohort study of ILD, elderly was defined as age ≥ 70 years. Diagnoses were derived from a multidisciplinary review. Differences between elderly and nonelderly groups were determined using the χ2 test and analysis of variance.\ud \ud Results\ud Of the 327 subjects enrolled, 80 (24%) were elderly. The majority of elderly subjects were white men. The most common diagnoses were unclassifiable ILD (45%), IPF (34%), connective tissue disease (CTD)-ILD (11%), and hypersensitivity pneumonitis (8%). Most elderly subjects (74%) with unclassifiable ILD had an imaging pattern inconsistent with usual interstitial pneumonia (UIP). There were no significant differences in pulmonary function or 3-year mortality between nonelderly and elderly subjects combined or in a subgroup analysis of those with IPF.\ud \ud Conclusions\ud Although IPF was the single most common diagnosis, the majority of elderly subjects had non-IPF ILD. Our findings highlight the need for every patient with new-onset ILD, regardless of age, to be surveyed for exposures and findings of CTD. Unclassifiable ILD was common among the elderly, but for most, the radiographic pattern was inconsistent with UIP. Although the effect of ILD may be more pronounced in the elderly due to reduced global functionality, ILD was not more severe or aggressive in this group.

Streptococcus anginosus has long been recognized to cause invasive pyogenic infections. This holds true for thoracic infections where S. anginosus has a propensity for abscess and empyema formation. Early diagnosis is important given the significant morbidity and mortality associated with thoracic S. anginosus infections. Yet, distinguishing thoracic S. anginosus clinically is difficult. We present three cases of thoracic S. anginosus that demonstrated radiographic extension across tissue planes, including the interlobar fissure, diaphragm, and chest wall. Few infectious etiologies are known to cross tissue planes. Accordingly, we propose S. anginosus be considered among the differential diagnosis of potential infectious etiologies causing radiographic extension across tissue planes.

The purpose of our study was to determine the relative frequencies of causes of widespread ground-glass opacity (GGO) in an unselected, consecutive patient population and to identify any associated imaging findings that can narrow or reorganize the differential.The study was approved by the center's IRB and is HIPPA compliant. Cases with widespread GGO in the radiology report were identified by searching the Radiology Information System. Medical records and CT scan examinations were reviewed for the causes of widespread GGO. Associations between a less dominant imaging finding and a particular diagnosis were analyzed with the chi square test. Our study group consisted of 234 examinations with 124 women and 110 men and a mean age of 53.7 years.A cause was established in 204 (87.2%) cases. Hydrostatic pulmonary edema was most common with 131 cases (56%). Interstitial lung diseases (ILD) were the next most common, most often hypersensitivity pneumonitis (HP) (n=12, 5%) and connective tissue disease related ILD (n=7, 3%). Infection accounted for 5% (12 cases). A few miscellaneous diseases accounted for 5 cases (2.1%). The combination of septal thickening and pleural effusions had a specificity of 0.91 for hydrostatic pulmonary edema (P.001) while centrilobular nodules and air trapping had a specificity of 1.0 for HP. In 24 (10.2%) patients, increased opacification from expiration was incorrectly interpreted as representing widespread ground glass opacity. The relative frequency of disease dramatically changed according to the setting. In the inpatient setting, diffuse alveolar disease and diffuse infection accounted for all of the known diagnoses. Pulmonary edema accounted for 75% of the diagnoses and diffuse infection accounted for approximately 7%. In the outpatient setting, interstitial lung disease was the most common cause, accounting for 26 of 53 cases (49%). Regarding immunocompromised patients, hydrostatic pulmonary edema was still the most common cause (46%) with diffuse infection (24%) the next most likely diagnosis. For patients with bone marrow suppression, 80% of the cases were due to opportunistic viral infection.Widespread GGO is most commonly a manifestation of hydrostatic pulmonary edema. Outpatients will most often have HP or connective tissue disease related ILD. Associated findings are helpful for the diagnosis of hydrostatic pulmonary edema and HP.

Multiple causes for air trapping as identified by expiratory computed tomography (CT) have been reported, but a unified evaluation schema has never been proposed.It was our purpose to identify imaging features that would help distinguish etiologies of mosaic air trapping.Cases with the term "air trapping" in the radiology report in 2010 were identified by searching the Radiology Information System of an academic tertiary care center and associated community hospital. Medical records and CT examinations were reviewed for the causes of air trapping.Causes for moderate to severe air trapping could be identified in 201 of 230 (87.4%) cases and could be subdivided into those associated with bronchiectasis (76 of 201, 38%), those associated with interstitial lung disease (62 of 201, 31%), those associated with tree-in-bud opacities (5 of 201, 2%), and those with air trapping alone (58 of 201, 29%). When found with bronchiectasis, nontuberculous mycobacteria, cystic fibrosis, idiopathic bronchiectasis, and transplant-related bronchiolitis obliterans were the most common causes of air trapping. When found with interstitial lung disease, sarcoidosis, hypersensitivity pneumonitis, or unspecified interstitial lung disease were the most common cause of air trapping. When found in isolation, chronic bronchitis, asthma, bronchiolitis obliterans, and unspecified small airways disease were the most common causes of air trapping. Unusual conditions causing isolated air trapping included vasculitis and diffuse idiopathic neuroendocrine cell hyperplasia.A variety of conditions can cause air trapping. Associated imaging findings can narrow the differential diagnosis.

Interstitial lung disease (ILD) is common among patients with both classic dermatomyositis (DM) and clinically amyopathic dermatomyositis (CADM), patients with classic skin manifestations without weakness. ILD prognosis is thought to be worse in patients with CADM, but this observation may be due primarily to an increased frequency of rapidly-progressive ILD. This article is protected by copyright. All rights reserved.

Multiple causes for tree-in-bud (TIB) opacities have been reported. However, to our knowledge the relative frequencies of the causes have not been evaluated. The purpose of this study was to determine the relative frequency of causes of TIB opacities and identify patterns of disease associated with TIB opacities.Cases with TIB opacities in the radiology report in 2010 were identified by searching the Radiology Information System. Medical records and CT scan examinations were reviewed for the causes of TIB opacities. Patterns of disease associated with TIB opacities were evaluated.Causes for TIB opacities were established in 166 of 406 (40.9%) cases. Respiratory infections (119 of 166, 72%) with mycobacteria (65 of 166, 39%), bacteria (44 of 166, 27%), viruses (four of 166, 3%), or multiple organisms (six of 166, 4%) were most common. Aspiration was the cause in 42 of 166 (25%). Alternating areas of normal lung with regions of small airways disease (TIB opacities, bronchiectasis) (random small airways pattern) was specific (0.92) for Mycobacterium avium complex infection. Nearly uniform distribution of bronchiectasis (widespread bronchiectasis pattern) was specific for "diseases predisposing to airway infection" (specificity 0.92), such as cystic fibrosis, primary ciliary dyskinesia, allergic bronchopulmonary aspergillosis, and immunodeficiency states. Consolidation and TIB opacities (bronchopneumonia pattern) were usually due to bacterial infection or aspiration. Dependent distribution (specificity 0.79) and esophageal abnormality (specificity 0.86) with TIB opacities were associated with aspiration. Chronicity of findings was associated with mycobacterial infection (Plt; .0001, sensitivity 0.96). Acuteness of findings was associated with bacterial infection (Plt; .001, specificity 0.87).TIB opacities are most often a manifestation of infections or aspiration. Patterns of disease can provide clues to the most likely diagnosis.

We retrospectively reviewed the CT findings of lower respiratory tract infection (LRTI) due to parainfluenza virus (PIV) to determine the imaging features of PIV infection and to identify any differences compared with the CT appearances of LRTIs due to respiratory syncytial virus (RSV), adenovirus, and influenza virus.The imaging features of LRTI from PIV over a 51-month period were retrospectively reviewed. The specific CT findings and overall pattern of infection in patients with LRTI due to PIV were recorded and were then compared with the CT appearances of RSV, adenovirus, and influenza LRTIs using data from a previous study.Twenty-four chest CT examinations of 24 patients with PIV infection were analyzed. Tree-in-bud opacities were the most common finding (13/24, 54%), and the airway-centric pattern of disease--characterized by combinations of bronchial wall thickening, tree-in-bud opacities, and peribronchiolar consolidation (bronchitis, bronchiolitis, and bronchopneumonia)--was the most common pattern (16/24, 67%). In comparison with previous data on RSV, adenovirus, and influenza virus, PIV showed tree-in-bud opacities and airway-centric patterns significantly more often than adenovirus or influenza virus. PIV and RSV showed similar CT findings and patterns of disease.Despite varying CT appearances of PIV LRTI, it most often shows airway-centric disease and is similar to the appearance of RSV infection, both of which are members of the Paramyxoviridae family of viruses.

Purpose To retrospectively determine the frequency, natural progression, radiographic characteristics, and primary cancer cell type of focal ground-glass opacities (GGOs) identified on serial radiographic examinations in patients with prior non-small cell lung carcinoma (NSCLC) resection. Methods One thousand three hundred and seventy-nine CT examinations in 154 patients with NSCLC resection between 1997 and 2008 were reviewed by two radiologists to determine the frequency of postoperative focal GGOs. Percentages, imaging characteristics and primary cancer cell types of GGOs that persisted, resolved, or resected were recorded. For persistent GGOs, growth rate was determined. Results Of 154 patients, 67 (44%) developed 174 GGO during a mean follow-up of 2.7 years (standard deviation 2.23 years, range 1 month to 10 years). Of these 174 opacities, 110 (63%) spontaneously resolved within 6 months. Of the remaining 64 lesions, 5 (3%) were resected and 59 (34%) persisted and demonstrated indolent growth with a median annual growth rate of 2.02 mm. Of the 59 persistent GGOs, 41 (69%) were nodularly shaped, 58 (95%) indistinctly marginated, 17 (29%) with pseudocavitation and 25 (42%) contained solid elements. Adenocarcinoma was the original resected cancer in more than half of these lesions (37 of 59, 63%). Conclusions In individuals who have undergone NSCLC resection, approximately 44% will develop focal GGO on follow-up CT examination. A majority of these GGOs will spontaneously resolve by 6 months after initial identification. As most persistent GGOs are indolent, we propose an initial 6-month interval reimaging once postoperative GGOs are detected followed by subsequent annual surveillance.

Klippel-Trenaunay syndrome (KTS) is a congenital disorder characterized by venous malformations and a predisposition to pulmonary embolism. We reviewed the imaging findings of 7 adult patients with KTS who underwent thoracic CT. While the superficial manifestations of KTS predominantly affect the extremities, patients frequently develop abnormalities of the pulmonary arterial system, particularly chronic thromboembolic pulmonary hypertension. Additionally, some patients are seen to develop pulmonary arteriolar aneurysms; the physiologic significance of this finding is unknown at this time. Radiologists should be aware of these potential findings and have a high index of suspicion for chronic PE in patients with KTS.

We retrospectively compared the CT findings of consecutive viral and bacterial lower respiratory tract infections (LRTIs) to determine their imaging appearance and any definable differences among the causative viruses and between the viral and bacterial infections.Imaging features of LRTI caused by influenza virus, respiratory syncytial virus (RSV), parainfluenza, adenovirus, and bacteria over a 33-month period were reviewed by three radiologists blinded to clinical and diagnostic information. Individual CT features and the dominant pattern of infection were recorded for each examination. Imaging characteristics were compared among the four respiratory viruses and between viral and bacterial infections.One hundred fifteen chest CT scans were analyzed (60 influenza virus, 19 RSV, 10 adenovirus, four parainfluenza virus, and 22 bacterial pneumonia LRTIs). Individual imaging findings and imaging patterns were seen in similar frequencies when we compared viral and bacterial LRTIs, with the exception of the diffuse airspace pattern, which was seen more frequently in bacterial infections. Although there was overlap in the imaging appearance of individual viruses, RSV and adenovirus tended to have characteristic imaging appearances. RSV presented with an airway-centric pattern of disease (13/19 cases [68%]) characterized by varying mixtures of tree-in-bud opacities and bronchial wall thickening, with or without peribronchiolar consolidation. Adenovirus typically appeared as multifocal consolidation or ground-glass opacity without airway inflammatory findings (7/10 cases [70%]).There is considerable overlap in the imaging appearance of viral and bacterial respiratory infections. However, some characteristic differences can be seen, especially with RSV and adenovirus infections.

The appearance of respiratory virus infection on thoracic computed tomography (CT) has been described only to a limited extent in the current literature, and viral pneumonias may be under-recognized by radiologists. Our objective was to describe thoracic CT findings in a broad range of adult inpatients with respiratory virus infections.A retrospective analysis of chest CTs was performed on symptomatic adult inpatients presenting with positive nucleic acid-based assays for 1 of 4 common community-acquired respiratory viruses. Forty-two patients with viral respiratory tract infections who underwent chest CT imaging were evaluated. The reviewer was blinded to virus type and patient information. CT findings were compared with CT reports produced at the time of the original study and correlated with clinical outcome measures.Influenza (n=21), adenovirus (n=9), respiratory syncytial virus (n=8), and parainfluenza (n=4) were represented among the cohort. Three patterns of the disease were seen with viral infection: (1) limited infection with normal imaging (21%), (2) bronchitis/bronchiolitis characterized by bronchial wall thickening and tree-in bud opacities (31%), and (3) pneumonia characterized by multifocal consolidation or ground-glass opacities (36%). Viral infection was suggested in only 4/42 (10%) of the original radiology reports, all of which had evidence of bronchitis/bronchiolitis on chest CT. Viral pneumonia, characterized by multifocal ground-glass opacities or multifocal consolidations, was interpreted as aspiration pneumonia or bacterial pneumonia in 15/16 (94%) of the original CT reports.CT scans of the inpatients with community-acquired viral infections most commonly show 1 of 2 patterns: consolidation and ground-glass opacities or bronchial wall thickening and tree-in-bud opacities. It is important that physicians interpreting CTs with multifocal consolidations and/or multifocal ground-glass opacities consider viral pneumonia when these findings are observed and recommend appropriate diagnostic testing when clinically warranted.

The purpose of this study was to determine, with CT as the reference standard, the ability of radiologists to detect pleural effusions on bedside chest radiographs.Images of 200 hemithoraces in 100 ICU patients undergoing chest radiography and CT within 24 hours were reviewed. Four readers with varying levels of experience reviewed the chest radiographs and predicted the likelihood of the presence of an effusion or parenchymal opacity on independent 5-point scales. The results were compared with the CT findings.All readers regardless of experience had similar accuracy in detecting pleural effusions. Among 117 pleural effusions, 66% were detected on chest radiographs (53%, 71%, and 92% of small, moderate, and large effusions) with 89% specificity. Similarly, 65% of all parenchymal opacities were detected on chest radiographs, also with 89% specificity. Most (93%) of the misdiagnosed pulmonary opacities were simply not seen. Meniscus, apical cap, lateral band, and subpulmonic opacity were highly specific findings but had low individual sensitivity for effusions. The finding of homogeneous opacity, including both layering and gradient opacities, was the most sensitive sign of effusion. Atelectasis can occasionally mimic the pleural veil sign of effusion, accounting for most false-positive findings.Radiologists interpreting bedside chest radiographs of ICU patients detect large pleural effusions 92% of the time and can exclude large effusions with high confidence. However, small and medium effusions often are misdiagnosed as parenchymal opacities (45%) or are not seen (55%). Pulmonary opacities often are missed (34%) but are rarely misdiagnosed as pleural effusions (7%).

Background CT scan measures of emphysema and airway disease have been correlated with lung function in cohorts of subjects with a range of COPD severity. The contribution of CT scan-assessed airway disease to objective measures of lung function and respiratory symptoms such as dyspnea in severe emphysema is less clear. Methods Using data from 338 subjects in the National Emphysema Treatment Trial (NETT) Genetics Ancillary Study, densitometric measures of emphysema using a threshold of −950 Hounsfield units (%LAA-950) and airway wall phenotypes of the wall thickness (WT) and the square root of wall area (SRWA) of a 10-mm luminal perimeter airway were calculated for each subject. Linear regression analysis was performed for outcome variables FEV 1 and percent predicted value of FEV 1 with CT scan measures of emphysema and airway disease. Results In univariate analysis, there were significant negative correlations between %LAA-950 and both the WT ( r = −0.28, p = 0.0001) and SRWA ( r = −0.19, p = 0.0008). Airway wall thickness was weakly but significantly correlated with postbronchodilator FEV 1 % predicted (R = −0.12, p = 0.02). Multivariate analysis showed significant associations between either WT or SRWA (β = −5.2, p = 0.009; β = −2.6, p = 0.008, respectively) and %LAA-950 (β = −10.6, p = 0.03) with the postbronchodilator FEV 1 % predicted. Male subjects exhibited significantly thicker airway wall phenotypes (p = 0.007 for WT and p = 0.0006 for SRWA). Conclusions Airway disease and emphysema detected by CT scanning are inversely related in patients with severe COPD. Airway wall phenotypes were influenced by gender and associated with lung function in subjects with severe emphysema.

OBJECTIVE. Our purpose was to show the CT and MRI findings of paragangliomas of the aortic body and the great vessels of the mediastinum.CONCLUSION. Paragangliomas of the aortic body and the great vessels have a characteristic imaging appearance. They originate from known sites of the branchiomeric paraganglia such as the aortic body. Knowledge of the location of the aortic body and other paraganglia combined with an appreciation of the how these tumors grow and displace neighboring structures will suggest a potential diagnosis of mediastinal paraganglioma.

To evaluate the rate of agreement of pulmonary embolism diagnosis in computed tomography (CT) pulmonary angiogram studies and to evaluate the rate of inaccurate interpretations in the community hospital setting.Using the keywords "pulmonary embolism/embolus/emboli," the radiology information system was searched for CT pulmonary angiograms performed over a 3-year period at three U.S. community hospitals. Studies containing probable or definite pulmonary emboli were independently reviewed by four subspecialty thoracic radiologists.Agreement about the presence of pulmonary embolism progressively decreased with decreasing diameter of pulmonary vascular lesions (P 0.0001). There was a sharp fall in observer agreement for pulmonary embolism of subsegmental lesions (P 0.0001). The frequency of agreement decreased with decreasing quality of the imaging examination (P 0.0001). Community radiologists were prone to false-positive pulmonary embolism diagnosis of subsegmental and/or small pulmonary arterial defects. The probability of a false-positive diagnosis and indeterminate examinations progressively increased with: (1) more peripheral location of the lesion, (2) decreased size (short-axis diameter) of the lesion, and (3) diminishing quality of the CT examination. Forty-eight of 177 (27%) of subsegmental vascular defects identified by community radiologists were deemed indeterminate, and 27 of 177 (15%) of subsegmental vascular defects were judged to be false positive for pulmonary embolism by the consensus diagnosis. Fifty-four of 274 (20%) vascular defects with short axis less than 6 mm were indeterminate for pulmonary embolism, and 37 of 274 (14%) of vascular defects with short axis less than 6 mm were false positive for pulmonary embolism. Eleven of 13 (85%) of vascular lesions identified as pulmonary emboli on the lowest-quality CT examinations were false positive or indeterminate for pulmonary embolism. False-positive examinations were most often due to respiratory motion artifact (19/38, 50%).There is relatively poor interobserver agreement for subsegmental and/or small pulmonary artery defects, especially in CT pulmonary angiograms degraded by technical artifacts. These factors can lead to an increased frequency of inaccurate interpretation or indeterminate diagnosis of subsegmental and/or small defects. Caution is indicated in interpreting the significance of small vascular defects in CT pulmonary angiograms.

Stephen Richardson, MD; Jeanne B. Budgin, DVM; Jacqueline M. Junkins-Hopkins, MD; Carmela C. Vittorio, MD; Jason Lee, MD; Wallace T. Miller, Jr, MD; Alain H. Rook, MD; Ellen J. Kim, MD; Departments of Dermatology (Drs Richardson, Junkins-Hopkins, Vittorio, Rook, and Kim) and Radiology (Dr Miller), University of Pennsylvania Health System; Department of Dermatology, University of Pennsylvania School of Veterinary Medicine (Dr Budgin); Department of Dermatology, Thomas Jefferson Medical College (Dr Lee), Philadelphia

Objectives/Hypothesis: The electronic nose is a sensor of volatile molecules that is useful in the analysis of expired gases. The device is well suited to testing the breath of patients receiving mechanical ventilation and is a potential diagnostic adjunct that can aid in the detection of patients with ventilatorassociated pneumonia. Study Design: A prospective study. Methods: We performed a prospective study of patients receiving mechanical ventilation in a surgical intensive care unit who underwent chest computed tomography (CT) scanning. A single attending radiologist reviewed the chest CT scans, and imaging features were recorded on a standardized form. Within 48 hours of chest CT scan, five sets of exhaled gas were sampled from the expiratory limb of the ventilator circuit. The gases were assayed with a commercially available electronic nose. Both linear and nonlinear analyses were performed to identify correlations between imaging features and the assayed gas signatures. Results: Twenty-five patients were identified, 13 of whom were diagnosed with pneumonia by CT scan. Support vector machine analysis was performed in two separate analyses. In the first analysis, in which a training set was identical to a prediction set, the accuracy of prediction results was greater than 91.6%. In the second analysis, in which the training set and the prediction set were different, the accuracy of prediction results was at least 80%, with higher accuracy depending on the specific parameters and models being used. Conclusion: The electronic nose is a new technology that continues to show promise as a potential diagnostic adjunct in the diagnosis of pneumonia and other infectious diseases.

The chest radiographic interpretation of interstitial lung disease is discussed by using a pattern approach. Patterns discussed are the Peripheral Reticular, Linear, Cystic, Nodular, and Ground-glass. The radiographic characteristics of each pattern are described, and the causes of each pattern are reviewed with attention to their usual clinical presentation. An understanding of the characteristic radiographic manifestations of various interstitial lung diseases can lead to improved diagnosis.

Streptococcus anginosus has long been recognized to cause invasive pyogenic infections. This holds true for thoracic infections where S. anginosus has a propensity for abscess and empyema formation. Early diagnosis is important given the significant morbidity and mortality associated with thoracic S. anginosus infections. Yet, distinguishing thoracic S. anginosus clinically is difficult. We present three cases of thoracic S. anginosus that demonstrated radiographic extension across tissue planes, including the interlobar fissure, diaphragm, and chest wall. Few infectious etiologies are known to cross tissue planes. Accordingly, we propose S. anginosus be considered among the differential diagnosis of potential infectious etiologies causing radiographic extension across tissue planes.

This study was undertaken to evaluate the efficacy of high resolution computed tomography (HRCT) in predicting the development of bronchiolitis obliterans syndrome (BOS) in lung transplant recipients. Fifty lung transplant patients who were clinically stable and without evidence of BOS were evaluated for the presence of four HRCT features reported to be associated with bronchiolitis obliterans: mosaic attenuation on inspiratory CT (mosaic perfusion), mosaic attenuation on expiratory CT (air trapping), bronchiectasis, and tree-in-bud opacities. CT exams were part of an annual surveillance process with the hope of predicting subsequent development of BOS. Diagnosis of BOS was made in 9 of 50 patients as indicated by a fall in FEV1 of greater than 20% of a stable baseline. None of the radiographic features associated with clinically established BOS were both sensitive and specific in the prediction of BOS. Air trapping demonstrated moderate sensitivity (56%, 5/9) and moderate specificity (76%, 35/46) for prediction of BOS in the year following the CT exam. Bronchiectasis, the most reliable indicator of the presence of BOS was a poor predictor of subsequent BOS with an 11% (1/9) sensitivity but had high specificity (96%, 44/46). No high resolution CT features accurately predicted the development of BOS.

The purpose of our study was to determine the CT findings in patients with esophagitis.A search of medical and radiology files revealed 29 patients with esophagitis in whom thoracic CT was performed within 1 month of the diagnosis. The CT scans were reviewed retrospectively for esophageal wall thickening, a target sign, or other abnormalities. The thickness of the esophageal wall was also measured on CT in these 29 patients and compared with a control group of 85 patients.We found that 16 patients (55%) with esophagitis had abnormal findings on CT, including a thickened esophageal wall (using 5 mm as the threshold for wall thickening) in all 16 (55%) and a target sign in five (17%). The overall mean esophageal wall thickness was 4.7 mm (standard deviation [SD], 2 mm; 95% confidence interval [CI], 0.7-8.7 mm) in patients with esophagitis versus a mean wall thickness of 2.9 mm (SD, 0.8 mm; 95% CI, 1.3-4.5 mm) in controls (p.001). Using the same 5-mm threshold for wall thickening, we found that only three (4%) of 85 controls had a thickened esophageal wall on CT.The majority of patients with esophagitis had abnormalities on CT, including a thickened esophageal wall (or =5 mm) in 55% and a target sign in 17%. Although barium studies and endoscopy are more sensitive modalities for detecting this condition, the CT finding of a relatively long segment of circumferential esophageal wall thickening, with or without a target sign, should suggest the diagnosis of esophagitis in the proper clinical setting.

Purpose: The purpose of this work was to characterize the cross-sectional imaging features of Kikuchi disease. Method: A search of our hospital records yielded three patients with pathologically proven Kikuchi disease. CT, MR, and ultrasound examinations of these patients were reviewed to characterize the imaging features of Kikuchi disease. Results: MRI of the neck in one patient, CT of the chest and abdomen in another,. and CT and MRI of the abdomen in the third demonstrated uniformly enhancing small lymph nodes in larger than normal numbers in the submandibular, axillary, gastrohepatic, celiac, periportal, paraaortic, retrocrural, mesenteric, and inguinal regions. Lymph node diameter was usually

In patients with chronic pulmonary embolism, pulmonary thromboendarterectomy may result in a unique form of noncardiogenic pulmonary edema termed reperfusion edema. This report reviews the authors' experience after pulmonary thromboendarterectomy with particular emphasis on the radiographic manifestations of reperfusion edema. The clinical and radiographic record of 25 patients who underwent pulmonary thromboendarterectomy at the University of Pennsylvania from 1985 through 1995 were reviewed. The zonal distribution of radiographic opacity, time to maximal opacity, and the time to clearance of reperfusion edema were determined. The relationship of these radiographic manifestations to clinical severity of disease and clinical outcome was examined. Reperfusion edema, characterized by patchy bilateral perihilar alveolar opacities, occurred in all but one patient. There is a lower lung zone predominance of opacities, but in individual cases, striking unilateral or haphazard arrangements of opacities may be seen. In this small sample of patients, no association between preoperative pulmonary arterial pressures and radiographic appearance or clinical outcome was found. However, severity of radiographic opacities, as measured by the extent of involved lung, correlated with disease severity, as measured by time to extubation and time to discharge. Pneumonia, defined as a radiographic opacity that evolves discordantly with the reperfusion edema opacities, occurred in 20% of cases. Reperfusion edema is a common consequence of pulmonary thromboendarterectomy. The severity of radiographic manifestations and clinical severity of disease are related. This characteristically appears as perihilar alveolar opacities.

The finding of a pulmonary infiltrate on chest radiograph may represent a spectrum of pathologic entities in the acutely ill hospitalized adult. Timely intervention depends on the advanced practice nurse's ability to devise a differential diagnosis based on the characteristics of the infiltrate and the clinical setting. Pulmonary infiltrates are described as interstitial or alveolar, diffuse or focal. Their presentation may be chronic or acute in nature. Understanding the nuances of chest radiographic interpretation provides the foundation on which the infiltrate is described and is therefore the first step in establishing the differential diagnosis. Thorough clinical assessment and thoughtful requisition of diagnostic studies are used to discriminate the disorders found in the differential diagnosis. Using an organized approach to describe the radiographic abnormality and define its clinical context, the advanced practice nurse can efficiently establish a diagnosis so that the work of treatment may begin.

Mucormycosis is an opportunistic, angioinvasive fungal infection characteristically affecting individuals with diabetes mellitus, chronic renal failure, and hematologic malignancies. In most cases it is a rapidly progressive infection with an 80% overall mortality. Radiographic manifestations are usually nonspecific focal consolidation or masses. The air crescent sign is a rare manifestation of angioinvasive fungi and indicates either aspergillosis or mucormycosis.

The toxicity and marginal effectiveness of cytotoxic chemotherapy in metastatic non-small cell lung cancer (NSCLC) necessitates the search for new agents. Preliminary data in lung cancer and other malignant and premalignant disorders have identified retinoid compounds as potentially useful antitumor agents. Twenty-eight patients with metastatic NSCLC were treated with oral all-trans retinoic acid in a phase II trial. The study population consisted of patients with excellent performance status and minimal weight loss. Toxicities were generally mild and included cutaneous effects, headache, and myalgia. A significant number of patients developed elevations of hepatic transaminases or hyperlipidemia and 3 patients had treatment-related leukocytosis. Two patients (8%) achieved a partial response, and 1 had a mixed response. The duration of remission in the 2 responders was 7 and 13 months and the median survival of all patients 7 months. Therefore, all-trans retinoic acid has minimal activity as a single agent in NSCLC but warrants further study in combination with biological agents and chemotherapy.

Aspergillus causes a variety of pulmonary diseases. For the most part, they can be divided into three groups: mycetoma, invasive aspergillosis, and allergic forms of aspergillosis. The mycetoma form of aspergillosis has no effective treatment other than surgery, which is reserved for the severely symptomatic patient, usually with massive hemoptysis. Invasive aspergillosis is a dangerous pulmonary infection seen in patients who are generally severely immunocompromised. It is treated with amphotericin B and success in treatment of this form of aspergillosis is limited. Two of the allergic forms of Aspergillus infection, allergic bronchopulmonary aspergillosis and bronchocentric granulomatosis, are treated with steroids. The third allergic type of reaction, hypersensitivity lung, is best treated by removal of the patient from exposure to the antigen. Although these are the characteristic forms of aspergillosis, there is occasional overlap of the different types of aspergillosis.

Background Pulmonary infection and tumor in the AIDS population has a variable clinical and radiographic presentation. The association between the radiographic presentation of pulmonary tuberculosis and CD4 T lymphocyte count in the HIV-infected patient is investigated in order to provide an empirical approach for early diagnosis, treatment, and isolation of infected subjects. Methods: A retrospective analysis of chest radiographs, CD4 T lymphocyte counts, and clinical history of 35 subjects from 3 urban hospitals was performed. All subjects were HIV-seropositive and had culture-proven pulmonary tuberculosis. Radiographs were evaluated for the presence of either a pattern characteristic of post-primary tuberculosis (typical pattern) or a pattern uncharacteristic of post-primary infection (atypical pattern). Results: Twenty-one of 26 subjects with a CD4 T lymphocyte count less than 0.20×10 9 cells/L, whereas only 1 of 9 subjects with a CD4 T lymphocyte count of 0.20×10 9 cells/L or more presented with an atypical pattern of pulmonary tuberculosis (p with atypical versus typical radiographic pattern of post-primary pulmonary tuberculosis were 0.069 × 10 9 cells/L (n=22) and 0.323×10 9 cells/L (n=13), respectively (p 9 cells/L). Atypical radiographic pattern included diffuse and lower lobar opacities, pleural effusion, mediastinal adenopathy, interstitial nodules, and a normal chest radiograph. Conclusion: AIDS patients presenting with CD4 count less than 0.20×10 9 cells/L and an atypical radiographic pattern for pulmonary tuberculosis are at risk for tuberculous infection requiring appropriate treatment and isolation until the diagnosis of pulmonary tuberculosis has been excluded.