Mediastinal lymph nodes and pulmonary nodules in children: MDCT findings in a cohort of healthy subjects.

OBJECTIVE: Existing data are very limited on incidentally detected pulmonary nodules or mediastinal lymph nodes in healthy children who undergo chest MDCT. We aimed to evaluate the prevalence, distribution, and average dimensions of these occasional findings in a cohort of otherwise healthy patients. MATERIALS AND METHODS: Two radiologists reviewed in consensus the scans of patients referred for chest MDCT during the preoperative workup for pectus carinatum or pectus excavatum treatments. Exclusion criteria included the presence of any documented malignancy (by date of MDCT or during the 2 years after the examination), history of recent infections, or trauma. Patients' records were assessed after 2 years for the development of any malignancy. RESULTS: A total of 99 individuals (63 boys, 36 girls; mean age, 13.5 years; range, 4-18 years) who fulfilled the study criteria were evaluated. The presence of at least one pulmonary nodule was observed in 75% of the patients, with a mean diameter of 2.8 mm. Of a total number of 225 pulmonary nodules, only 24 (10.7%) were calcified. Mediastinal lymph nodes were also identified in 81% of the cases, with a maximum diameter of 7 mm (smallest axis). CONCLUSION: The presence of pulmonary nodules or mediastinal lymph nodes on the basis of preoperative chest MDCT scans in healthy children is frequent. Given that 95% of the nodules and 100% of the lymph nodes measured less than 6 mm and 7 mm, respectively, we conclude that incidental findings under these limits are very unlikely to be pathologic.

CT quantification of large opacities and emphysema in silicosis: correlations among clinical, functional, and radiological parameters.

BACKGROUND: The assessment of the extent of silicosis on chest radiographs is subjective and could be more standardized by using computed tomography (CT) quantification methods. We propose a semiautomatic method of quantifying the anatomical lung damage (LD) (the sum of the emphysema and large opacities volumes) measured by CT densitovolumetry in complicated silicosis. METHODS: Twenty-three nonsmokers with complicated silicosis were included. Large opacities were recorded as size A, B, or C according to the size of the opacities on chest radiographs. Pulmonary function tests (PFT) were assessed by spirometry and the carbon monoxide diffusion capacity. Total lung capacity (TLC) was measured by helium dilution, and total lung volume (TLV) was measured by CT quantification (TLVct). CT images were postprocessed using CT densitovolumetry to measure the TLVct, large opacities volume, emphysema volume (EV), and emphysema index (EI). RESULTS: Significant correlations were observed between the EV and the forced vital capacity (r = 0.41, p = 0.04), TLC (r = 0.44, p = 0.03), and residual volume (RV) (r = 0.49, p = 0.01). A correlation also was observed between the LD% and RV (r = 0.43, p = 0.03) and between the LD and RV (r = 0.47, p = 0.02). CONCLUSIONS: The PFT findings were correlated with the EV, EI, LD, and LD%, but they were not correlated with the large opacities volume. These results suggest that the emphysema volume, more than the large opacities volume, is responsible for functional impairment in patients with complicated silicosis.

High-resolution computed tomographic findings of cocaine-induced pulmonary disease: a state of the art review.

Cocaine is the most commonly used illicit drug among patients presenting at hospital emergency departments and the most frequent cause of drug-related deaths reported by medical examiners. Various respiratory problems temporally associated with cocaine use have been reported. Acute and chronic uses also are responsible for lung complications, such as pulmonary edema, alveolar hemorrhage, pulmonary hypertension, organizing pneumonia, emphysema, barotrauma, infection, cancer, eosinophilic disease, and aspiration pneumonia. Although most imaging findings are nonspecific, they may raise suspicion of a cocaine-related etiology when considered together with patients' profiles and medical histories. This literature review describes cocaine-induced diseases with pulmonary involvement, with an emphasis on high-resolution chest computed tomographic findings and patterns.

Reversed halo sign in active pulmonary tuberculosis: criteria for differentiation from cryptogenic organizing pneumonia.

OBJECTIVE: The purpose of this study was to compare the morphologic characteristics of the "reversed halo" sign caused by tuberculosis with those caused by cryptogenic organizing pneumonia (COP) and to determine whether high-resolution CT (HRCT) can differentiate between these two conditions. MATERIALS AND METHODS: We retrospectively reviewed the HRCT scans of patients with the reversed halo sign caused by active tuberculosis and HRCT scans of patients with the reversed halo sign caused by COP. The study included 12 patients with active pulmonary tuberculosis (10 women and two men) and 10 patients with biopsy-proven COP (five women and five men). Tuberculosis was diagnosed by culture of sputum, bronchoalveolar lavage, or biopsy specimen. All patients underwent HRCT, and the images were reviewed by two chest radiologists who reached decisions by consensus. RESULTS: HRCT scans of all patients with active tuberculosis showed reversed halos with nodular walls; in most cases (10/12), we also observed nodules inside the halos. None of the HRCT scans of the COP cases reviewed had halos with nodular walls or nodules inside them. We also observed parenchymal abnormalities, such as consolidation, ground-glass, and linear opacities, associated with the reversed halo sign. Neither the number of reversed halo sign lesions nor the associated parenchymal lesions discriminated between tuberculosis and COP. Nevertheless, the association of the reversed halo sign with nodular walls or nodules inside the halo was seen only in tuberculosis patients. CONCLUSION: Although COP is considered the most frequent cause of the reversed halo sign, the presence of nodular walls or nodules inside the reversed halo strongly favors a diagnosis of active pulmonary tuberculosis rather than COP.

Correlative anatomy for the mediastinum.

Diseases of the mediastinum comprise a wide spectrum of benign and malignant entities that share the same anatomic site within the chest. Correct management often requires a multidisciplinary approach. Diagnostic imaging modalities such as computed tomography (CT), magnetic resonance imaging (MRI), ultrasonography, and positron emission tomography play a major role in the diagnosis of mediastinal diseases and in guiding minimally invasive diagnostic procedures, minimizing the risk of imaging-guided biopsies. This article describes the mediastinal anatomy, correlating the findings of plain radiography, CT, and MRI.

Neurofibromatosis type 1: evaluation by chest computed tomography.

OBJECTIVE: The aim of this study was to evaluate chest computed tomography (CT) findings in patients diagnosed with neurofibromatosis type 1 (NF1). MATERIAL AND METHODS: This was a retrospective study in which we reviewed the chest CT scans of 14 patients diagnosed with NF1 and neurofibromatosis-associated diffuse lung disease (NF-DLD). The sample comprised eight women and six men. The median age was 55 years (range, 11-75 years). The diagnosis of NF1 was made on the basis of the diagnostic criteria established by the U.S. National Institutes of Health. The images were analyzed by two chest radiologists, who reached decisions by consensus. RESULTS: The predominant CT finding of NF-DLD was multiple cysts, which were observed in 13 patients (92.9%), followed by emphysema, in eight (57.1%) and subpleural bullae, in six (42.9%). Other findings included subcutaneous neurofibromas, in 12 patients (85.7%), ground-glass opacities, in one (7.1%), and tracheobronchial neurofibromas, in one (7.1%). The pulmonary abnormalities were bilateral in 12 cases (85.7%). The abnormalities were predominantly in the upper lung fields in eight cases (57.1%), and their distribution was random in 11 (78.6%). CONCLUSION: Pulmonary cysts, emphysema, and subpleural bullae appear to be the chest CT findings that are most characteristic of NF-DLD.

OBJETIVO: O objetivo deste estudo foi avaliar os achados pulmonares na tomografia computadorizada do tórax de pacientes diagnosticados com neurofibromatose tipo 1 (NF1). MATERIAIS E MÉTODOS: Foram revisados, retrospectivamente, os achados tomográficos de 14 pacientes com doença pulmonar difusa associada à NF1 (NF-DPD). A amostra incluiu oito mulheres e seis homens, com idade entre 11 e 75 anos (mediana de idade de 55 anos). O diagnóstico foi estabelecido com base em critérios diagnósticos predeterminados pelo National Institutes of Health dos Estados Unidos. As imagens foram analisadas de forma independente por dois radiologistas, que chegaram a um consenso. RESULTADOS: Os achados tomográficos predominantes foram múltiplos cistos em 13 pacientes (92,9%), enfisema em oito (57,1%) e bolhas subpleurais em seis (42,9%). Achados associados incluíram neurofibromas cutâneos e subcutâneos em 12 pacientes (85,7%), opacidades em vidro fosco em um (7,1%) e neurofibromas traqueobrônquicos em um (7,1%). As anormalidades pulmonares foram bilaterais em 12 casos (85,7%). Houve predomínio nos terços superiores em oito (57,1%) pacientes e se distribuíram randomicamente pelos pulmões em 11 (78,6%). CONCLUSÃO: Os achados tomográficos pulmonares mais frequentes na NF-DPD foram os cistos pulmonares, o enfisema e as bolhas subpleurais.

Tomographic findings in bronchial atresia.

OBJECTIVE: To evaluate computed tomography (CT) findings in 23 patients with bronchial atresia. MATERIALS AND METHODS: The CT images were reviewed by two radiologists who reached decisions by consensus. We included only patients who presented with abnormalities on CT and in whom the diagnosis had been confirmed by pathological examination of the surgical specimen (if the lesion was resected). The CT scans were assessed in order to identify the main findings and to map the distribution of the lesions (i.e., to determine whether the pulmonary involvement was unilateral or bilateral). RESULTS: The main CT finding was the combination of bronchocele and hyperinflation of the distal lung. That combination was observed in all of the patients. The lesions were unilateral in all 23 cases, being seen predominantly in the left upper lobe, followed by the right lower lobe, right upper lobe, middle lobe, and left lower lobe. CONCLUSION: The diagnosis of bronchial atresia can be reliably made on the basis of a finding of bronchocele accompanied by hyperinflation of the adjacent lung parenchyma.

OBJETIVO: Analisar os achados na tomografia computadorizada (TC) de tórax de 23 pacientes com atresia brônquica. MATERIAIS E MÉTODOS: As imagens de TC foram avaliadas por dois observadores e os casos discordantes foram resolvidos por consenso. Os critérios de inclusão foram a presença de anormalidades na TC compatíveis com atresia brônquica e/ou diagnóstico confirmado por exame anatomopatológico das peças cirúrgicas para os pacientes submetidos a ressecção cirúrgica. As TCs foram avaliadas quanto aos principais achados de imagem, à distribuição das lesões, ao envolvimento pulmonar unilateral ou bilateral. RESULTADOS: Os principais achados na TC foram a presença de broncocele, hiperinsuflação do parênquima pulmonar ou ambos. A combinação desses achados foi encontrada em todos os pacientes. Em relação à distribuição, o envolvimento foi unilateral nos 23 casos. Quando se consideraram os lobos mais acometidos, o lobo superior esquerdo foi o mais acometido, seguido do lobo inferior direito, lobo superior direito, lobo médio e lobo inferior esquerdo. CONCLUSÃO: O diagnóstico de atresia brônquica pode ser feito em presença de broncocele associada com hiperinsuflação do parênquima pulmonar adjacente.

Lipoid pneumonia in 53 patients after aspiration of mineral oil: comparison of high-resolution computed tomography findings in adults and children.

OBJECTIVE: To evaluate the high-resolution computed tomography (HRCT) findings in 53 patients with exogenous lipoid pneumonia and to compare the imaging features of adults and children. MATERIALS AND METHODS: The study included 35 children and 18 adults. Statistical comparisons of findings in the 2 age groups were performed using either Pearson chi2 or Fisher exact test, as appropriate, at 5% significance level. RESULTS: The main HRCT findings included air-space consolidation, ground glass attenuation, air-space nodules, and crazy-paving pattern. Abnormalities predominated in the posterior regions of the right lung. The right lower lobe was most likely to show severe involvement. CONCLUSIONS: The presence of air-space consolidation, the involvement of upper right lobe, and the central and posterior distribution of the lesions were more common in children, whereas the crazy-paving pattern and random localization were significantly more frequent in adults. The other findings were not different between the 2 groups.

CT quantification of emphysema in young subjects with no recognizable chest disease.

OBJECTIVE: The purpose of this prospective study was to evaluate volumetric CT emphysema quantification (CT densitovolumetry) in a young population with no recognizable lung disease. SUBJECTS AND METHODS: A cohort of 30 nonsmoking patients with no recognizable lung disease (16 men, 14 women; age range, 19-41 years) underwent inspiratory and expiratory CT, after which the data were postprocessed for volumetric quantification of emphysema (threshold, -950 HU). Correlation was tested for age, weight, height, sex, body surface area (BSA), and physical activity. Normal limits were established by mean +/- 1.96 SD. RESULTS: No correlation was found between the measured volumes and age or physical activity. Correlation was found between BSA and normal lung volume in inspiration (r = 0.69, p = 0.000), shrink volume (i.e., difference in total lung volume in inspiration and in expiration) (r = 0.66, p = 0.000), and percentage of shrink volume (r = 0.35, p = 0.05). For an alpha error of 5%, the limits of normality based on this sample are percentage of emphysema in inspiration, 0.35%; percentage of emphysema in expiration, 0.12%; and maximum lung volume in expiration, 3.6 L. The maximum predicted percentage of shrink volume can be calculated as %SV = 29.43% + 16.97% x BSA (+/- 1.96 x 7.61%). CONCLUSION: Young healthy nonsmokers with no recognizable lung disease can also show a small proportion of emphysematous-like changes on CT densitovolumetry when a threshold of -950 HU is used. Reference values should be considered when applying the technique for early detection or grading of emphysema and when studying aging lungs.

Neurofibromatosis type 1: State-of-the-art review with emphasis on pulmonary involvement.

Neurofibromatosis type 1 (NF-1), also known as von Recklinghausen's disease, is an autosomal dominant dysplasia of the ectoderm and mesoderm with a variable clinical expression, but near-complete penetrance before the age of 5 years. The estimated incidence is 1 in 3000 births. NF-1 is characterized by collections of neurofibromas, café-au-lait spots, axillary and inguinal freckling, and pigmented hamartomas in the iris (Lisch nodules). Pulmonary manifestations of NF-1, which usually include bilateral basal reticulations and apical bullae and cysts, are reported in 10-20% of adult patients. Clinically, neurofibromatosis-associated diffuse lung disease (NF-DLD) usually presents with nonspecific respiratory symptoms, including dyspnea on exertion, shortness of breath, and chronic cough or chest pain, at the time of diagnosis. Computed tomography (CT) is highly accurate for the identification and characterization of NF-DLD; it is the most reliable method for the diagnosis of this lung involvement. Various CT findings of NF-DLD, including cysts, bullae, ground-glass opacities, bibasilar reticular opacities, and emphysema, have been described in patients with NF-1. The typical CT pattern, however, is characterized by upper-lobe cystic and bullous disease, and basilar interstitial lung disease. Currently, the goal of NF-DLD treatment is the earliest possible diagnosis, focusing on symptom relief and interventions that positively alter the course of the disease, such as smoking cessation. The aim of this review is to describe the main clinical, pathological, and imaging aspects of NF-1, with a focus on pulmonary involvement.

Laryngotracheobronchial papillomatosis: chest CT findings.

To evaluate the findings on chest CTs in 16 patients (8 men and 8 women) with laryngotracheobronchial papillomatosis. This was a retrospective study involving patients ranging from 2 to 72 years of age. The evaluation of the CT scans was independently performed by two observers, and discordant results were resolved by consensus. The inclusion criteria were presence of abnormalities on the CT scans, and the diagnosis was confirmed by anatomopathological examination of the papillomatous lesions. The most common symptoms were hoarseness, cough, dyspnea, and recurrent respiratory infections. The major CT findings were nodular formations in the trachea, solid or cavitated nodules in the lung parenchyma, air trapping, masses, and consolidation. Nodular formations in the trachea were observed in 14 patients (87.5%). Only 2 patients had lesions in lung parenchyma without tracheal involvement. Only 1 patient had no pulmonary dissemination of the disease, showing airway involvement only. Solid and cavitated lung nodules were observed in 14 patients (87.5%) and 13 (81.2%), respectively. Masses were observed in 6 patients (37.5%); air trapping, in 3 (18.7%); consolidation in 3 (18.7%); and pleural effusion, in 1 (6.3%). Pulmonary involvement was bilateral in all cases. The most common tomography findings were nodular formations in the trachea, as well as solid or cavitated nodules and masses in the lung parenchyma. Malignant transformation of the lesions was observed in 5 cases.

Tomographic findings in bronchial atresia / Achados tomográficos na atresia brônquica

Abstract Objective: To evaluate computed tomography (CT) findings in 23 patients with bronchial atresia. Materials and Methods: The CT images were reviewed by two radiologists who reached decisions by consensus. We included only patients who presented with abnormalities on CT and in whom the diagnosis had been confirmed by pathological examination of the surgical specimen (if the lesion was resected). The CT scans were assessed in order to identify the main findings and to map the distribution of the lesions (i.e., to determine whether the pulmonary involvement was unilateral or bilateral). Results: The main CT finding was the combination of bronchocele and hyperinflation of the distal lung. That combination was observed in all of the patients. The lesions were unilateral in all 23 cases, being seen predominantly in the left upper lobe, followed by the right lower lobe, right upper lobe, middle lobe, and left lower lobe. Conclusion: The diagnosis of bronchial atresia can be reliably made on the basis of a finding of bronchocele accompanied by hyperinflation of the adjacent lung parenchyma.

Resumo Objetivo: Analisar os achados na tomografia computadorizada (TC) de tórax de 23 pacientes com atresia brônquica. Materiais e Métodos: As imagens de TC foram avaliadas por dois observadores e os casos discordantes foram resolvidos por consenso. Os critérios de inclusão foram a presença de anormalidades na TC compatíveis com atresia brônquica e/ou diagnóstico confirmado por exame anatomopatológico das peças cirúrgicas para os pacientes submetidos a ressecção cirúrgica. As TCs foram avaliadas quanto aos principais achados de imagem, à distribuição das lesões, ao envolvimento pulmonar unilateral ou bilateral. Resultados: Os principais achados na TC foram a presença de broncocele, hiperinsuflação do parênquima pulmonar ou ambos. A combinação desses achados foi encontrada em todos os pacientes. Em relação à distribuição, o envolvimento foi unilateral nos 23 casos. Quando se consideraram os lobos mais acometidos, o lobo superior esquerdo foi o mais acometido, seguido do lobo inferior direito, lobo superior direito, lobo médio e lobo inferior esquerdo. Conclusão: O diagnóstico de atresia brônquica pode ser feito em presença de broncocele associada com hiperinsuflação do parênquima pulmonar adjacente.

Neurofibromatosis type 1: evaluation by chest computed tomography / Neurofibromatose tipo 1: estudo por tomografia computadorizada do tórax

Abstract Objective: The aim of this study was to evaluate chest computed tomography (CT) findings in patients diagnosed with neurofibromatosis type 1 (NF1). Material and Methods: This was a retrospective study in which we reviewed the chest CT scans of 14 patients diagnosed with NF1 and neurofibromatosis-associated diffuse lung disease (NF-DLD). The sample comprised eight women and six men. The median age was 55 years (range, 11-75 years). The diagnosis of NF1 was made on the basis of the diagnostic criteria established by the U.S. National Institutes of Health. The images were analyzed by two chest radiologists, who reached decisions by consensus. Results: The predominant CT finding of NF-DLD was multiple cysts, which were observed in 13 patients (92.9%), followed by emphysema, in eight (57.1%) and subpleural bullae, in six (42.9%). Other findings included subcutaneous neurofibromas, in 12 patients (85.7%), ground-glass opacities, in one (7.1%), and tracheobronchial neurofibromas, in one (7.1%). The pulmonary abnormalities were bilateral in 12 cases (85.7%). The abnormalities were predominantly in the upper lung fields in eight cases (57.1%), and their distribution was random in 11 (78.6%). Conclusion: Pulmonary cysts, emphysema, and subpleural bullae appear to be the chest CT findings that are most characteristic of NF-DLD.

Resumo Objetivo: O objetivo deste estudo foi avaliar os achados pulmonares na tomografia computadorizada do tórax de pacientes diagnosticados com neurofibromatose tipo 1 (NF1). Materiais e Métodos Foram revisados, retrospectivamente, os achados tomográficos de 14 pacientes com doença pulmonar difusa associada à NF1 (NF-DPD). A amostra incluiu oito mulheres e seis homens, com idade entre 11 e 75 anos (mediana de idade de 55 anos). O diagnóstico foi estabelecido com base em critérios diagnósticos predeterminados pelo National Institutes of Health dos Estados Unidos. As imagens foram analisadas de forma independente por dois radiologistas, que chegaram a um consenso. Resultados: Os achados tomográficos predominantes foram múltiplos cistos em 13 pacientes (92,9%), enfisema em oito (57,1%) e bolhas subpleurais em seis (42,9%). Achados associados incluíram neurofibromas cutâneos e subcutâneos em 12 pacientes (85,7%), opacidades em vidro fosco em um (7,1%) e neurofibromas traqueobrônquicos em um (7,1%). As anormalidades pulmonares foram bilaterais em 12 casos (85,7%). Houve predomínio nos terços superiores em oito (57,1%) pacientes e se distribuíram randomicamente pelos pulmões em 11 (78,6%). Conclusão: Os achados tomográficos pulmonares mais frequentes na NF-DPD foram os cistos pulmonares, o enfisema e as bolhas subpleurais.

Thoracic lymphadenopathy in benign diseases: A state of the art review.

Lymphadenopathy is a common radiological finding in many thoracic diseases and may be caused by a variety of infectious, inflammatory, and neoplastic conditions. This review aims to describe the patterns of mediastinal and hilar lymphadenopathy found in benign diseases in immunocompetent patients. Computed tomography is the method of choice for the evaluation of lymphadenopathy, as it is able to demonstrate increased size of individual nodes, abnormalities of the interface between the mediastinum and lung, invasion of surrounding fat, coalescence of adjacent nodes, obliteration of the mediastinal fat, and hypo- and hyperdensity in lymph nodes. Intravenous contrast enhancement may be needed to help distinguish nodes from vessels. The most frequent infections resulting in this finding are tuberculosis and fungal disease (particularly histoplasmosis and coccidioidomycosis). Sarcoidosis is a relatively frequent cause of lymphadenopathy in young adults, and can be distinguished from other diseases - especially when enlarged lymph nodes are found to be multiple and symmetrical. Other conditions discussed in this review are silicosis, drug reactions, amyloidosis, heart failure, Castleman's disease, viral infections, and chronic obstructive pulmonary disease.

PET/CT imaging in lung cancer: indications and findings.

The use of PET/CT imaging in the work-up and management of patients with lung cancer has greatly increased in recent decades. The ability to combine functional and anatomical information has equipped PET/CT to look into various aspects of lung cancer, allowing more precise disease staging and providing useful data during the characterization of indeterminate pulmonary nodules. In addition, the accuracy of PET/CT has been shown to be greater than is that of conventional modalities in some scenarios, making PET/CT a valuable noninvasive method for the investigation of lung cancer. However, the interpretation of PET/CT findings presents numerous pitfalls and potential confounders. Therefore, it is imperative for pulmonologists and radiologists to familiarize themselves with the most relevant indications for and limitations of PET/CT, seeking to protect their patients from unnecessary radiation exposure and inappropriate treatment. This review article aimed to summarize the basic principles, indications, cancer staging considerations, and future applications related to the use of PET/CT in lung cancer.

Birt-Hogg-Dubé syndrome. State-of-the-art review with emphasis on pulmonary involvement.

BACKGROUND: Birt-Hogg-Dubé syndrome (BHDS) is a rare, inherited autosomal-dominant disorder characterized by the development of cutaneous lesions, renal tumors, pulmonary cysts, and spontaneous pneumothorax. The gene responsible for BHDS is located on the short arm of chromosome 17 (17p11.2) and codes for the protein folliculin, which is believed to be an oncogene suppressor protein. METHODS: We reviewed currently published literature on the main characteristics of BHDS. RESULTS: Pulmonary cysts and spontaneous pneumothorax are often the presenting manifestations that lead to a final diagnosis in family members affected by the syndrome. CONCLUSIONS: Certain imaging characteristics of pulmonary cysts, including size and location, can suggest the diagnosis of BHDS based on chest computed tomography alone. The main concern in patients with BHDS is the increased risk of renal carcinoma. The aim of this review is to describe the main pathological, clinical, and imaging aspects of BHDS, ranging from its genetic basis to treatment, with emphasis on pulmonary involvement.