The disease caused by the new coronavirus (COVID-19) was restricted to China but quickly spread to other Asian countries and later to the Western countries, categorized as a pandemic by the World Health Organization. Its diagnosis is primarily dependent on viral detection in the airways. The available kits are, however, limited, do not have high sensitivity and their result takes time. In this scenario, computed tomography emerges as an efficient and available method with high sensitivity. It is up to us radiologists to readily recognize the findings related to this disease. The aim of this article is to demonstrate the main tomographic findings in symptomatic respiratory patients infected with COVID-19 in order to assist colleagues in this critical moment.

Keywords: Coronavirus; COVID-19; Multislice computed tomography.

The objective of this article is to share the strategy we used in order to restructure the radiology and diagnostic imaging department of a referral institution during the coronavirus disease 2019 pandemic, on the basis of the current recommendations. It is essential to integrate the work of supervisors, preceptors, and residents, maintaining communication and sharing decisions, with mutual support, as well as to determine the best strategy to be adopted in this scenario of uncertainty and constant change, while also ensuring adequate emotional support for all parties.

Keywords: Pandemics; Radiology; Internship and residency.

Radiotherapy plays a central role in the palliative and curative treatment of neoplasms of the chest wall or intrathoracic structures. However, despite technical advances, radiotherapy can alter previously normal organs and tissues, those alterations presenting as various types of imaging findings. Post-radiation alterations must be promptly recognized by radiologists, in order to avoid confusion between complications of radiotherapy and the recurrence of a tumor. This pictorial essay aims to illustrate different thoracic changes after radiotherapy.

Keywords: Radiotherapy; Tomography, X-ray computed; Magnetic resonance imaging; Diagnostic imaging; Thoracic neoplasms.

Vanishing bone metastasis (pseudopathological vertebral body enhancement) is a pitfall in the interpretation of contrast-enhanced computed tomography (CT) scans of patients with thoracic vein obstruction, mainly in the superior vena cava and brachiocephalic veins, typically being related to thrombosis due to malignant tumors. On the basis of the CT findings, pseudopathological vertebral body enhancement can be misdiagnosed as sclerotic bone metastasis, leading to unnecessary treatment. Although not rare, pseudopathological vertebral body enhancement is usually underdiagnosed by radiologists. The aim of this study is to review the pathophysiology of this phenomenon, illustrating the most common collateral venous pathways in thoracic vein obstruction and making the correlation with the CT findings.

Keywords: Neoplasm metastasis/physiopathology; Bone and bones/diagnostic imaging; Tomography, X-ray computed; Diagnostic errors; Venous thrombosis; Collateral circulation.

OBJECTIVE: To characterize the main causes of the reversed halo sign (RHS) on computed tomography (CT) of the chest and its imaging features.
MATERIALS AND METHODS: This was a retrospective study reviewing all chest CT scans for which the report contained the term "reversed halo sign" among those performed between 2015 and 2020 at a tertiary care hospital.
RESULTS: A total of 286 cases were identified, and the corresponding CT images and clinical data were reviewed. In this population, the most common cause of an RHS was pulmonary infarction (in 42%), followed by cryptogenic organizing pneumonia (in 17%) and bacterial pneumonia (in 16%). In addition, the CT characteristics of the RHS were identified in various conditions, such as pulmonary thromboembolism with pulmonary infarction, in which the RHS was typically smooth-walled and solitary with a peripheral distribution.
CONCLUSION: The RHS can be observed in many contexts, and its CT characteristics, in combination with the clinical picture, can help narrow the differential diagnosis.

Keywords: Tomography, X-ray computed/methods; Respiratory tract infections/diagnostic imaging; Pulmonary embolism/diagnostic imaging; Lung diseases, interstitial/diagnostic imaging.