OBJECTIVE: To evaluate the accuracy of chest computed tomography (CT) in patients with suspected severe acute respiratory syndrome-related coronavirus-2 (SARS-CoV-2) infection at a cancer center. Materials and METHODS: This retrospective single-center study selected 91 patients who had chest CT and real-time polymerase chain reaction (RT-PCR) test collected at the same day. CT results were classified in negative, typical, indeterminate or atypical findings. Diagnostic accuracy, sensitivity and specificity were calculated for two different scenarios: in the first, only typical findings on CT were considered positive; in the second, both typical and indeterminate findings were considered positive. RESULTS: Mean patients’ age was 58.2 years, most were male (60.4%) and had prior diagnosis of cancer (85.7%). CT showed typical findings in 28.6%, indeterminate findings in 24.2% and atypical findings in 26.4%. RT-PCR results were positive for SARS-CoV-2 in 27.5%. The sensitivity, specificity and accuracy in the first and second scenarios were respectively 64.0%, 84.8% and 79.1%, and 92.0%, 62.1% and 70.3%. CONCLUSION: CT has a high accuracy for the diagnosis of SARS-CoV-2 infection. Different interpretation criteria can provide either high sensitivity or high specificity. CT should be integrated as a triage test in resource-constrained environments during the pandemic to assist in the optimization of PCR-tests, isolation beds and intensive care units.

Keywords: Computed tomography; Severe acute respiratory syndrome; Coronavirus infections; Cancer.

OBJECTIVE: To assess the practical aspects of the use of various gadolinium-based contrast agents (GBCAs) by radiologists. MATERIALS AND METHODS: Ten experienced radiologists from different regions of Brazil participated in a Delphi panel querying their use of various GBCAs, including linear and macrocyclic classes (1.0 and 0.5 M), in terms of the choice of agent, volume and dosage of the agents, and associated safety concerns. RESULTS: The response rate was 100% for all questions. GBCAs are safe in terms of acute adverse reactions, and nephrogenic systemic fibrosis is rare. The deposition of gadolinium in the brain and other tissues is a concern among the experts. Macrocyclic agents are preferable to linear agents; an injection volume below 0.1 mL/kg of a 1.0 M agent could result in good-quality images with additional long-term safety, but there is no published evidence to support this recommendation. The majority of experts preferred not to administer GBCAs to pregnant patients. CONCLUSION: When choosing a GBCA, it is important to consider the characteristics of the gadolinium deposition in patient tissues and minimize potential risks. Furthermore, medical education programs are needed to increase the awareness of the potential risks of gadolinium deposition and thus avoid instances of overexposure to the contrast agent.

Keywords: Contrast media; Gadolinium; Magnetic resonance imaging; Gadolinium-based contrast agents; Safety.

OBJECTIVE: To compare two different fat-saturated magnetic resonance imaging (MRI) techniques—STIR and T2 SPAIR—in terms of image quality, as well as in terms of their diagnostic performance in detecting sacroiliac joints (SIJ) active inflammation. MATERIALS AND METHODS: We included 69 consecutive patients with suspected spondyloarthritis undergoing MRI between 2012 and 2014. The signal-to-noise ratio (SNR) was calculated with the method recommended by the American College of Radiology. Two readers evaluated SIJ MRI following ASAS criteria to assess diagnostic performance regarding the detection of active SIJ inflammation. T1 SPIR Gd+ sequence was used as the reference standard. RESULTS: The mean SNR was 72.8 for the T1 SPIR Gd+ sequence, compared with 14.1 and 37.6 for the STIR and T2 SPAIR sequences, respectively. The sensitivity and specificity of STIR and SPAIR T2 sequences did not show any statistically significant differences for the diagnosis of sacroiliitis with active inflammation. CONCLUSION: Our results corroborate those in the recent literature suggesting that STIR sequences are not superior to T2 SPAIR sequences for SIJ evaluation in patients with suspected spondyloarthritis. On 1.5-T MRI, T2-weighted SPAIR sequences provide better SNRs than do STIR sequences, which reinforces that T2 SPAIR sequences may be an advantageous option for the evaluation of sacroiliitis.

Keywords: Sacroiliitis; Sacroiliac joint; Magnetic resonance imaging; Spondyloarthropathies; Signal-to-noise ratio.

OBJECTIVE: To evaluate the accuracy of steady-state free precession (SSFP) unenhanced magnetic resonance angiography (MRA) at 1.5 T for the identification of multiple renal arteries, using computed tomography angiography (CTA) as the reference standard. MATERIALS AND METHODS: This was a prospective study involving 39 patients (26 males; mean age, 62.6 years) who underwent CTA and unenhanced MRA to evaluate the proximal and middle segments of the renal arteries. The analysis was performed in two phases: the quality of unenhanced MRA images was classified as diagnostic or nondiagnostic for the presence of multiple renal arteries by two independent readers; two other independent readers then evaluated the images previously classified as being of diagnostic quality. The sensitivity, specificity, and overall accuracy of unenhanced MRA were calculated, CTA being used as the reference standard. The kappa statistic was used in order to calculate interobserver agreement. RESULTS: The image quality of unenhanced MRA was considered diagnostic in 70–90% of the extrarenal arterial segments. The CTA examination revealed 19 multiple renal arteries (8 on the right and 11 on the left). The accuracy of unenhanced MRA for the identification of multiple renal arteries was greater than 90%, with a sensitivity of 72.7–100% and a specificity of 96.3–100%. CONCLUSION: Unenhanced MRA provides high quality imaging of the extrarenal segments of renal arteries. This method may be used as an alternative for the evaluation of the renal arteries, given that it has an accuracy comparable to that of CTA.

Keywords: Computed tomography angiography; Magnetic resonance angiography; Kidney; Kidney transplantation; Diagnostic techniques, urological.

OBJECTIVE: To evaluate the effect that transitioning from a model of general radiology reporting to one of subspecialized radiology reporting has on report turnaround times (TATs) and on productivity in the radiology department of a hospital in a middle-income country. MATERIALS AND METHODS: The reporting workflow in our radiology department was changed from general reporting (any radiologist reporting imaging studies for any specialty) to subspecialized reporting (radiologists exclusively reporting imaging studies that fall within their subspecialty—abdominal, musculoskeletal, cardiothoracic, emergency, or neurological imaging). This was a retrospective study in which we compared general reporting with subspecialized reporting in terms of the following variables: the TAT; the proportions of reports completed within 2 h and within 24 h (TAT-2h and TAT-24h, respectively); and productivity. Data were collected over two 24-month periods (2015–2016 for general reporting and 2017–2018 for subspecialized reporting). RESULTS: A total of 208,516 reports were generated. The median report TAT decreased from 49.1 h and 52.9 h in 2015 and 2016, respectively, to 16.1 h and 15.2 h in 2017 and 2018, respectively (p < 0.001). The TAT-2h also improved, increasing from 8.7% and 7.9% in 2015 and 2016, respectively, to 52.0% and 61.3% in 2017 and 2018, respectively (p < 0.001), as did the TAT-24h, which increased from 12.1% and 14.1% in 2015 and 2016, respectively, to 74.3% and 78.7% in 2017 and 2018, respectively (p < 0.001). Between the two periods, the total number of scans performed increased by 33% (p = 0.001). CONCLUSION: The implementation of a subspecialized reporting system significantly improved the median TAT for radiology reports, as well as increasing the TAT-2h and TAT-24h, during a time of increased productivity.

Keywords: Radiologists/classification; Medical records/standards; Radiology department, hospital/organization & administration; Radiology information systems/standards; Radiology/organization & administration; Specialization/trends.

Lung ultrasound is a well-defined diagnostic modality in the point of care emergency medicine concept. In the context of the coronavirus disease 2019 (COVID-19) pandemic, the lung ultrasound assumed an essential role in this disease, with a valid correlation of the imaging results with computed tomography. Recognize how the diagnostic possibilities of ultrasound in the approach of COVID-19 and its differential diagnoses are fundamental.

Keywords: Lung ultrasound; Chest; Lung; COVID-19; Coronavirus; Pneumonia; Ultrasonography.

We describe a target sign on chest CT characterized by a combination of peripheral ring-like opacity and a central nodular groundglass opacity surrounding a vessel in a couple with COVID-19 pneumonia confirmed by real-time reverse transcriptase fluorescence polymerase chain reaction sputum analysis.

Keywords: Coronavirus infection; Coronavirus; Computed tomography.

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.

Cholangiopathies are chronic diseases that affect the bile ducts, comprising a heterogeneous group of progressive and potentially fatal entities. The diagnosis of these diseases is a great challenge for radiologists because of the overlapping of their clinical, biochemical, and imaging findings. Nevertheless, identifying the precise etiology is crucial, given that the therapeutic options are distinct and influence the prognosis of the patient. The purpose of this review article is to discuss some of the non-neoplastic causes of cholangiopathies and to provide a useful diagnostic algorithm.

Keywords: Bile duct diseases; Liver cirrhosis; Cholangiography; Computed tomography; Magnetic resonance imaging.

Intracranial calcifications, which are common in the daily routine of radiologists, can have a physiological or pathological origin. Determining the cause of intracranial calcifications can represent a challenge. The anatomical location, distribution, dimensions and morphology of such calcifications are important findings, which, in conjunction with the clinical history and age group, can facilitate the differential diagnosis. The aim of this pictorial essay is to demonstrate the different types of intracranial calcifications and their origins. The images evaluated were those stored in picture archiving and communication systems. All of the cases included were studied by computed tomography, magnetic resonance imaging, or both. We identified, classified, and described 64 types of intracranial calcifications.

Keywords: Intracranial calcifications; Computed tomography, Magnetic resonance imaging.