Imaging findings in COVID-19 pneumonia

The coronavirus disease (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARSCoV-2), emerged in Wuhan city and was declared a pandemic in March 2020. Although the virus is not restricted to the lung parenchyma, the use of chest imaging in COVID-19 can be especially useful for patients with moderate to severe symptoms or comorbidities. This article aimed to demonstrate the chest imaging findings of COVID-19 on different modalities: chest radiography, computed tomography, and ultrasonography. In addition, it intended to review recommendations on imaging assessment of COVID-19 and to discuss the use of a structured chest computed tomography report. Chest radiography, despite being a low-cost and easily available method, has low sensitivity for screening patients. It can be useful in monitoring hospitalized patients, especially for the evaluation of complications such as pneumothorax and pleural effusion. Chest computed tomography, despite being highly sensitive, has a low specificity, and hence cannot replace the reference diagnostic test (reverse transcription polymerase chain reaction). To facilitate the confection and reduce the variability of radiological reports, some standardizations with structured reports have been proposed. Among the available classifications, it is possible to divide the radiological findings into typical, indeterminate, atypical, and negative findings. The structured report can also contain an estimate of the extent of lung involvement (e.g., more or less than 50% of the lung parenchyma). Pulmonary ultrasonography can also be an auxiliary method, especially for monitoring hospitalized patients in intensive care units, where transfer to a tomography scanner is difficult

Computed tomography quantification of lung disease in bronchiectasis patients

Introdução: Escores tomográficos visuais são utilizados para quantificação do acometimento pulmonar em pacientes com bronquiectasias, porem, são subjetivos, requerem treinamento prévio e demandam tempo considerável para sua realização. O objetivo deste estudo e avaliar a densitometria pulmonar por tomografia computadorizada (DPTC) como método de quantificação automática do acometimento pulmonar em pacientes com bronquiectasias de etiologia não fibrose cística, correlacionando-a com dados da prova de função pulmonar (PFP) e comparando-a com o escore tomográfico visual (CF-CT). Métodos: Entre 2014 e 2017, foram recrutados 100 adultos com bronquiectasias de etiologia não fibrose cística. Os pacientes realizaram TC de tórax em inspiração e expiração, prova de função pulmonar, pletismografia e medida da capacidade de difusão do monóxido de carbono (DLCO). Foram calculados o escore tomográfico visual, escores prognósticos multidimensionais (FACED e BSI) e parâmetros da DPTC. Resultados: Parâmetros da DPTC (curtose e assimetria) apresentaram correlação com o volume expiratório forcado em 1 segundo (VEF1) (r=0,32 e r=0,34; p 60). Além disso, a DPTC foi mais rápida do que a analise visual. Conclusão: A DPTC e um método rápido, objetivo e reprodutível que pode ser utilizado para quantificação automática do acometimento pulmonar em pacientes com bronquiectasias. Na nossa população a quantificação automática de aprisionamento aéreo apresentou desempenho melhor que o escore tomográfico visual para discriminar pacientes de alto risco e pacientes com aprisionamento aéreo grave, sugerindo que este método possa contribuir na avaliação dos pacientes com bronquiectasias, especialmente na quantificação de aprisionamento aéreoIntroduction: Visual computed tomography (CT) scoring systems are used for quantitative evaluation of lung disease in bronchiectasis patients but are subjective, require previous training and are time-consuming. The aim of this study was to use CT lung densitometry, an automated method of lung disease quantification in the evaluation of non-cystic fibrosis bronchiectasis patients and to investigate the relationship of this CT quantification system with pulmonary function test (PFT) and visual CT score system (CF-CT score). Methods: From 2014 to 2017, 100 consecutive adult patients with non-cystic fibrosis bronchiectasis underwent inspiratory and expiratory volumetric chest CT and PFT. CT lung densitometry parameters, visual CF-CT score and multidimensional prognostic scores (FACED and BSI) were calculated in all patients and correlated to PFT. Results: CT lung densitometry parameters (kurtosis and skewness) correlated with forced expiratory volume in 1 second (FEV1) (r=0.32 e r=0.34; p 60). Also, CT lung densitometry is a faster method of evaluation than visual CT scoring. Conclusion: CT lung densitometry is a fast, objective and reproductible method of automated quantification of lung disease in bronchiectasis patients. In our population, automated air trapping quantification performed better than visual CT score in the diagnosis of high-risk patients and severe air trapping, suggesting this method could be used in the evaluation of bronchiectasis patients, especially for the quantification of air trappin

Diagnostic reference level quantities for adult chest and abdomen-pelvis CT examinations: correlation with organ doses

Key points 1. DRL quantities and target-organ doses can support guidance’s to optimization criteria. 2. Organ doses inside imaged area are higher than in other regions. 3. Statistical significance between organ doses and the DRL quantities are presented. 4. Results reinforce the importance on the adequate choice of the scan length

Computed tomography in hypersensitivity pneumonitis: main findings, differential diagnosis and pitfalls

Hypersensitivity pneumonitis (HP) is a disease with variable clinical presentation in which inflammation in the lung parenchyma is caused by the inhalation of specific organic antigens or low molecular weight substances in genetically susceptible individuals. Alterations of the acute, subacute and chronic forms may eventually overlap, and the diagnosis based on temporality and presence of fibrosis (acute/inflammatory HP vs. chronic HP) seems to be more feasible and useful in clinical practice. Differential diagnosis of chronic HP with other interstitial fibrotic diseases is challenging due to the overlap of the clinical history, and the functional and imaging findings of these pathologies in the terminal stages. Areas covered: This article reviews the essential features of HP with emphasis on imaging features. Moreover, the main methodological limitations of high-resolution computed tomography (HRCT) interpretation are discussed, as well as new perspectives with volumetric quantitative CT analysis as a useful tool for retrieving detailed and accurate information from the lung parenchyma. Expert commentary: Mosaic attenuation is a prominent feature of this disease, but air trapping in chronic HP seems overestimated. Quantitative analysis has the potential to estimate the involvement of the pulmonary parenchyma more accurately and could correlate better with pulmonary function results

Computed tomography in hypersensitivity pneumonitis: main findings, differential diagnosis and pitfalls

<p><b>Introduction</b>: Hypersensitivity pneumonitis (HP) is a disease with variable clinical presentation in which inflammation in the lung parenchyma is caused by the inhalation of specific organic antigens or low molecular weight substances in genetically susceptible individuals. Alterations of the acute, subacute and chronic forms may eventually overlap, and the diagnosis based on temporality and presence of fibrosis (acute/inflammatory HP <i>vs</i>. chronic HP) seems to be more feasible and useful in clinical practice. Differential diagnosis of chronic HP with other interstitial fibrotic diseases is challenging due to the overlap of the clinical history, and the functional and imaging findings of these pathologies in the terminal stages.</p> <p><b>Areas covered</b>: This article reviews the essential features of HP with emphasis on imaging features. Moreover, the main methodological limitations of high-resolution computed tomography (HRCT) interpretation are discussed, as well as new perspectives with volumetric quantitative CT analysis as a useful tool for retrieving detailed and accurate information from the lung parenchyma.</p> <p><b>Expert commentary</b>: Mosaic attenuation is a prominent feature of this disease, but air trapping in chronic HP seems overestimated. Quantitative analysis has the potential to estimate the involvement of the pulmonary parenchyma more accurately and could correlate better with pulmonary function results.</p

The Diagnostic Challenge of an Infrequent Spectrum of Cryptococcus Infection

Cryptococcal infection results from inhalation of fungal spores and usually is confined to the lungs, but may disseminate systemically. Radiologically, cryptococcal infection has multiple forms of presentation. The diagnosis is usually based on fungal isolation from cultured clinical specimens. Long term antifungal therapy is recommended, but surgical procedures may eventually be necessary when large thoracic symptomatic masses are present. We report a case of a 41-year-old male, immunocompetent, investigating a palpable mass in the left supraclavicular region associated with unintentional weight loss over the last three months. He also reported chest pain in this period. Chest X-ray, ultrasonography, and computed tomography were performed, which diagnosed a mediastinal and left supraclavicular mass, interpreted as lymph node conglomerates of unknown etiology. He also underwent a biopsy of the left supraclavicular mass for etiological determination by histopathology, which confirmed cryptococcosis infection. Although very infrequent, mediastinal cryptococcal infection (simulating masses) is a challenging but important differential diagnosis of benign and malignant lesions, since its treatment is usually clinical