RadioGraphics Update: Pictorial Guide to CAD-RADS 2.0.

Editor's Note.-RadioGraphics Update articles supplement or update information found in full-length articles previously published in RadioGraphics. These updates, written by at least one author of the previous article, provide a brief synopsis that emphasizes important new information such as technological advances, revised imaging protocols, new clinical guidelines involving imaging, or updated classification schemes.

Quantitative Dual-Energy Computed Tomography Predicts Regional Perfusion Heterogeneity in a Model of Acute Lung Injury.

OBJECTIVE: The aims of this study were to investigate the ability of contrast-enhanced dual-energy computed tomography (DECT) for assessing regional perfusion in a model of acute lung injury, using dynamic first-pass perfusion CT (DynCT) as the criterion standard and to evaluate if changes in lung perfusion caused by prone ventilation are similarly demonstrated by DECT and DynCT. METHODS: This was an institutional review board-approved study, compliant with guidelines for humane care of laboratory animals. A ventilator-induced lung injury protocol was applied to 6 landrace pigs. Perfused blood volume (PBV) and pulmonary blood flow (PBF) were respectively quantified by DECT and DynCT, in supine and prone positions. The lungs were segmented in equally sized regions of interest, namely, dorsal, middle, and ventral. Perfused blood volume and PBF values were normalized by lung density. Regional air fraction (AF) was assessed by triple-material decomposition DECT. Per-animal correlation between PBV and PBF was assessed with Pearson R. Regional differences in PBV, PBF, and AF were evaluated with 1-way analysis of variance and post hoc linear trend analysis (α = 5%). RESULTS: Mean correlation coefficient between PBV and PBF was 0.70 (range, 0.55-0.98). Higher PBV and PBF values were observed in dorsal versus ventral regions. Dorsal-to-ventral linear trend slopes were -10.24 mL/100 g per zone for PBV (P < 0.001) and -223.0 mL/100 g per minute per zone for PBF (P < 0.001). Prone ventilation also revealed higher PBV and PBF in dorsal versus ventral regions. Dorsal-to-ventral linear trend slopes were -16.16 mL/100 g per zone for PBV (P < 0.001) and -108.2 mL/100 g per minute per zone for PBF (P < 0.001). By contrast, AF was lower in dorsal versus ventral regions in supine position, with dorsal-to-ventral linear trend slope of +5.77%/zone (P < 0.05). Prone ventilation was associated with homogenization of AF distribution among different regions (P = 0.74). CONCLUSIONS: Dual-energy computed tomography PBV is correlated with DynCT-PBF in a model of acute lung injury, and able to demonstrate regional differences in pulmonary perfusion. Perfusion was higher in the dorsal regions, irrespectively to decubitus, with more homogeneous lung aeration in prone position.

Dual-energy CT and coronary imaging.

Dual-energy computed tomography has been proposed for enhancing the evaluation of coronary artery disease in many fronts. However, the clinical translation of such applications has followed a slower pace of clinical translation. This paper will review the evidence supporting the use of dual-energy computed tomography in coronary artery disease (CAD) and provide some practical illustrations, while underscoring the challenges and gaps in knowledge that have contributed to this phenomenon.

Future Directions in Coronary CT Angiography: CT-Fractional Flow Reserve, Plaque Vulnerability, and Quantitative Plaque Assessment.

Coronary computed tomography angiography (CCTA) is a well-validated and noninvasive imaging modality for the assessment of coronary artery disease (CAD) in patients with stable ischemic heart disease and acute coronary syndromes (ACSs). CCTA not only delineates the anatomy of the heart and coronary arteries in detail, but also allows for intra- and extraluminal imaging of coronary arteries. Emerging technologies have promoted new CCTA applications, resulting in a comprehensive assessment of coronary plaques and their clinical significance. The application of computational fluid dynamics to CCTA resulted in a robust tool for noninvasive assessment of coronary blood flow hemodynamics and determination of hemodynamically significant stenosis. Detailed evaluation of plaque morphology and identification of high-risk plaque features by CCTA have been confirmed as predictors of future outcomes, identifying patients at risk for ACSs. With quantitative coronary plaque assessment, the progression of the CAD or the response to therapy could be monitored by CCTA. The aim of this article is to review the future directions of emerging applications in CCTA, such as computed tomography (CT)-fractional flow reserve, imaging of vulnerable plaque features, and quantitative plaque imaging. We will also briefly discuss novel methods appearing in the coronary imaging scenario, such as machine learning, radiomics, and spectral CT.

Electronic Cigarette or Vaping-associated Lung Injury (EVALI): The Tip of the Iceberg.

The Centers for Disease Control and Prevention, the U.S. Food and Drug Administration, and state and local health departments have begun an investigation into the lung injury attributed to the use of electronic cigarette (e-cigarette) or vaping products. A clinical case of a 24-year-old man who used e-cigarette products regularly and presented with shortness of breath, productive cough, chest pain, and fever for 1 week was discussed. Radiographic and CT findings in that patient were reviewed. Recent cases of e-cigarette-associated lung injury from the literature were summarized to continue the dialogue and encourage radiologists to research this relatively new and specific type of lung injury. © RSNA, 2019.

Pulmonary vasculitis: diagnosis and endovascular therapy.

Pulmonary vasculitides are caused by a heterogeneous group of diseases with different clinical features and etiologies. Radiologic manifestations depend on the predominant type of vessel involved, which are grouped into large, medium, or small-sized vessels. Diagnosing pulmonary vasculitides is a challenging task, and radiologists play an important role in their management by providing supportive evidence for diagnosis and opportunities for minimally invasive therapy. This paper aims to present a practical approach for understanding the vasculitides that can affect the pulmonary vessels and lungs. We will describe and illustrate the main radiologic findings, discussing opportunities for minimally invasive treatment.

Chronic pulmonary embolism: diagnosis.

Chronic thromboembolic pulmonary hypertension (CTEPH) is a complication of venous thromboembolic disease. Differently from other causes of pulmonary hypertension, CTEPH is potentially curable with surgery (thromboendarterectomy) or balloon pulmonary angioplasty. Imaging plays a central role in CTEPH diagnosis. The combination of techniques such as lung scintigraphy, computed tomography and magnetic resonance angiography provides non-invasive anatomic and functional information. Conventional pulmonary angiography (CPA) with right heart catheterization (RHC) is considered the gold standard method for diagnosing CTEPH. In this review, we discuss the utility of these imaging techniques in the diagnosis of CTEPH.

Acometimento da função ventricular direita em pacientes com esclerose sistêmica e doença pulmonar intersticial: avaliação pelo doppler tecidual / Impairment of right ventricular function in patients with systemic sclerosis and interstitial lung disease: tissue doppler evaluation

Introdução: A esclerose sistêmica (ES) é uma doença autoimune do tecido conjuntivo que cursa com fibrose e disfunção microvascular. O envolvimento dos órgãos viscerais, incluindo os pulmões e o coração, é a principal causa de óbito na ES. Nesse contexto, analisamos a relação entre os parâmetros ventriculares direitos (VD) pela ecocardiografia com Doppler tecidual e o acometimento pulmonar em pacientes com ES. Métodos: Os pacientes que preencheram os Critérios de Classificação da ES de 2013 foram submetidos à ecocardiografia com Doppler tecidual para avaliação da função sistólica (fração de ejeção) ventricular esquerda (VE), enquanto a função sistólica do VD foi avaliada por meio da fração de variação de área do VD (fractional area change ­ FAC), velocidade (sistólica) do Doppler tecidual, índice de desempenho miocárdico (IDM) e excursão sistólica do plano anular tricúspide (TAPSE). A pressão sistólica pulmonar foi estimada por insuficiência tricúspide. A tomografia computadorizada de alta resolução (TCAR) de tórax avaliou a presença de fibrose pulmonar. De acordo com os resultados da TCAR, os pacientes foram divididos em 2 subgrupos: Grupo I, incluindo pacientes com fibrose pulmonar (n=26), e Grupo II sem fibrose (n=17). Resultados: Entre os 43 pacientes com ES, a maioria era do sexo feminino (86%) com idade de 51±12 anos. Todos os pacientes apresentavam função ventricular sistólica normal, avaliada pela FEVE>55% e FAC VD>35%. Não houve diferença significativa em termos de idade ou duração da doença para os grupos. Exceto pela diminuição das velocidades do Doppler tecidual em pacientes com fibrose pulmonar, todos os índices de desempenho do VD foram semelhantes. Conclusão: Em pacientes com ES e fibrose pulmonar, o Doppler tecidual identifica acometimento miocárdico longitudinal precoce do VD, apesar do desempenho sistólico radial preservado do VD.(AU)

Introduction: Systemic sclerosis (SSc) is an autoimmune tissue connective disease that courses with fibrosis and microvascular dysfunction. Involvement of the visceral organs, including the lungs and heart, is the main cause of death among patients with SSc. In this context, here we analyzed the relationship between right ventricle (RV) parameters assessed by tissue Doppler echocardiography and lung involvement in patients with SSc. Methods: Patients fulfilling the 2013 SSc Classification Criteria underwent tissue Doppler echocardiography for the assessment of left ventricular (LV) systolic function (ejection fraction) and RV fractional area change (FAC), tissue Doppler s' (systolic) velocity, myocardial performance index, and tricuspid annular plane systolic excursion for the assessment of RV systolic function. Pulmonary systolic pressure was estimated using tricuspid regurgitation. Chest high-resolution computed tomography was used to evaluate the presence of pulmonary fibrosis. The patients were divided into two subgroups accordingly: Group I, patients with pulmonary fibrosis (n=26); and Group II, those without fibrosis (n=17). Results: Among the 43 patients with SSc, most were female (86%), and the mean age was 51 ± 12 years. All patients had normal systolic ventricular function as evidenced by an LV ejection fraction > 55% and an RV FAC > 35%. No significant intergroup difference was noted in age or disease duration. Except for a decreased tissue Doppler s' velocity in patients with lung fibrosis, all indexes of RV performance were similar. Conclusion: In patients with SSc and pulmonary fibrosis, tissue Doppler identified early RV longitudinal myocardial involvement despite preserved RV radial systolic performance.(AU)

Pulmonary involvement in rheumatoid arthritis: evaluation by radiography and spirometry.

OBJECTIVE: To determine whether simple diagnostic methods can yield relevant disease information in patients with rheumatoid arthritis (RA). METHODS: Patients with RA were randomly selected for inclusion in a cross-sectional study involving clinical evaluation of pulmonary function, including pulse oximetry (determination of SpO2, at rest), chest X-ray, and spirometry. RESULTS: A total of 246 RA patients underwent complete assessments. Half of the patients in our sample reported a history of smoking. Spirometry was abnormal in 30% of the patients; the chest X-ray was abnormal in 45%; and the SpO2 was abnormal in 13%. Normal chest X-ray, spirometry, and SpO2 were observed simultaneously in only 41% of the RA patients. A history of smoking was associated with abnormal spirometry findings, including evidence of obstructive or restrictive lung disease, and with abnormal chest X-ray findings, as well as with an interstitial pattern on the chest X-ray. Comparing the patients in whom all test results were normal (n = 101) with those in whom abnormal test results were obtained (n = 145), we found a statistically significant difference between the two groups, in terms of age and smoking status. Notably, there were signs of airway disease in nearly half of the patients with minimal or no history of tobacco smoke exposure. CONCLUSIONS: Pulmonary involvement in RA can be identified through the use of a combination of diagnostic methods that are simple, safe, and inexpensive. Our results lead us to suggest that RA patients with signs of lung involvement should be screened for lung abnormalities, even if presenting with no respiratory symptoms.

Reduction of poor contrast enhancement of the pulmonary artery in computed tomography angiography using an alternative respiratory maneuver.

PURPOSE: The aim of the study was to compare the effects of different respiratory maneuvers in computed tomography pulmonary angiography for the diagnosis of pulmonary embolism (PE) on the contrast enhancement of pulmonary circulation and on the quality of lung window images. MATERIALS AND METHODS: A retrospective analysis of 520 examinations, half obtained after deep inspiration followed by breath-holding and half solely during breath-holding. Subjective quality analyses and objective measurements of pulmonary arterial enhancement and lung parenchyma attenuation were performed. RESULTS: Elimination of deep inspiration reduced suboptimal opacification of the pulmonary artery (PA), from 7.3% to 2.7%, with 2.7% of the deep inspiration scans having attenuation values <150 Hounsfield units (HU). The prevalence of PE was similar between the groups (19% vs. 23%, respectively), with excellent interobserver diagnostic agreement (κ=0.89 to 0.91). Lung windows were compromised in 6.9% of the studies with respiratory pause, and these examinations had a higher attenuation of the lung parenchyma (median: -709.8 HU) compared with deep inspiration (-794.8 HU). A positive correlation between attenuation of the PA and the ascending aorta was observed (r=0.40 to 0.56). CONCLUSIONS: Eliminating deep inspiration before image acquisition had opposite effects with the same magnitude: it caused a reduction in inadequate PA enhancement at the cost of an increased number of nondiagnostic lung images and did not compromise diagnostic consistency for PE.

Bullet embolism of pulmonary artery: a case report.

The authors report the case of a patient victim of gunshots, with a very rare complication: venous bullet embolism from the left external iliac vein to the lingular segment of the left pulmonary artery. Diagnosis is made with whole-body radiography or computed tomography. Digital angiography is reserved for supplementary diagnosis or to be used as a therapeutic procedure.

Relatamos o caso de um paciente vítima de tiros por arma de fogo e com uma rara complicação: embolia venosa de um projétil desde a veia ilíaca externa esquerda até o ramo lingular da artéria pulmonar esquerda. Radiografias de corpo inteiro ou tomografia computadorizada do corpo inteiro devem ser utilizadas. Angiografia digital fica reservada para complementação diagnóstica ou como procedimento terapêutico.

Acute tracheobronchitis caused by Aspergillus: case report and imaging findings.

Acute tracheobronchitis is a rare manifestation of invasive aspergillosis, generally occurring in severely immunocompromised patients. The authors report the case of a patient presenting with this condition after bone-marrow transplantation, with emphasis on tomographic findings.

Traqueobronquite aguda é uma forma rara da aspergilose invasiva e geralmente ocorre em pacientes com imunodepressão grave. Relatamos o caso de um paciente no pós-transplante de medula óssea com a manifestação desta doença, dando ênfase aos achados tomográficos encontrados.

Thanatophoric dysplasia: case report of an autopsy complemented by postmortem computed tomographic study.

Thanatophoric dysplasia (TD) is one of the most common lethal skeletal dysplasias, which was first designated as thanatophoric dwarfism and described in 1967. The authors report a case of a Caucasian girl with TD, born to a 31-year-old woman without comorbidities. The newborn presented respiratory distress immediately after delivery, progressing to death in less than 2 hours. An autopsy was carried out after postmortem tomographic examination. The autopsy findings depicted extensive malformations of the skeletal system and the brain. The aim of this report is to discuss the pathogenesis and correlate the morphologic features of TD that were disclosed at the tomography and the autopsy.

Differences between postmortem computed tomography and conventional autopsy in a stabbing murder case.

OBJECTIVE: The aim of the present work is to analyze the differences and similarities between the elements of a conventional autopsy and images obtained from postmortem computed tomography in a case of a homicide stab wound. METHOD: Comparison between the findings of different methods: autopsy and postmortem computed tomography. RESULTS: In some aspects, autopsy is still superior to imaging, especially in relation to external examination and the description of lesion vitality. However, the findings of gas embolism, pneumothorax and pulmonary emphysema and the relationship between the internal path of the instrument of aggression and the entry wound are better demonstrated by postmortem computed tomography. CONCLUSIONS: Although multislice computed tomography has greater accuracy than autopsy, we believe that the conventional autopsy method is fundamental for providing evidence in criminal investigations.

Pneumomediastinum, subcutaneous emphysema, and pneumothorax after a pulmonary function testing in a patient with bleomycin-induced interstitial pneumonitis.

Spontaneous pneumomediastinum is an uncommon event, the clinical picture of which includes retrosternal chest pain, subcutaneous emphysema, dyspnea, and dysphonia. The pathophysiological mechanism involved is the emergence of a pressure gradient between the alveoli and surrounding structures, causing alveolar rupture with subsequent dissection of the peribronchovascular sheath and infiltration of the mediastinum and subcutaneous tissue with air. Known triggers include acute exacerbations of asthma and situations that require the Valsalva maneuver. We described and documented with HRCT scans the occurrence of pneumomediastinum after a patient with bleomycin-induced interstitial lung disease underwent pulmonary function testing. Although uncommon, the association between pulmonary function testing and air leak syndromes has been increasingly reported in the literature, and lung diseases, such as interstitial lung diseases, include structural changes that facilitate the occurrence of this complication.

Transdiaphragmatic intercostal hernia: imaging aspects in three cases.

Transdiaphragmatic intercostal hernia is uncommon and mostly related to blunt or penetrating trauma. We report three similar cases of cough-induced transdiaphragmatic intercostal hernia, highlighting the anatomic findings obtained with different imaging modalities (radiography, ultrasonography, CT, and magnetic resonance) in each of the cases.

Coronary computed tomography angiography with 320-row detector and using the AIDR-3D: initial experience.

Coronary computed tomography angiography (coronary CTA) is a powerful non-invasive imaging method to evaluate coronary artery disease. Nowadays, coronary CTA estimated effective radiation dose can be dramatically reduced using state-of-the-art scanners, such as 320-row detector CT (320-CT), without changing coronary CTA diagnostic accuracy. To optimize and further reduce the radiation dose, new iterative reconstruction algorithms were released recently by several CT manufacturers, and now they are used routinely in coronary CTA. This paper presents our first experience using coronary CTA with 320-CT and the Adaptive Iterative Dose Reduction 3D (AIDR-3D). In addition, we describe the current indications for coronary CTA in our practice as well as the acquisition standard protocols and protocols related to CT application for radiation dose reduction. In conclusion, coronary CTA radiation dose can be dramatically reduced following the "as low as reasonable achievable" principle by combination of exam indication and well-documented technics for radiation dose reduction, such as beta blockers, low-kV, and also the newest iterative dose reduction software as AIDR-3D.

Pancreatic iron stores assessed by magnetic resonance imaging (MRI) in beta thalassemic patients.

PURPOSE: To assess the correlation between MRI findings of the pancreas with those of the heart and liver in patients with beta thalassemia; to compare the pancreas T2* MRI results with glucose and ferritin levels and labile plasma iron (LPI). MATERIALS AND METHODS: We retrospectively evaluated chronically transfused patients, testing glucose with enzymatic tests, serum ferritin with chemiluminescence, LPI with cellular fluorescence, and T2* MRI to assess iron content in the heart, liver, and pancreas. MRI results were compared with one another and with serum glucose, ferritin, and LPI. Liver iron concentration (LIC) was determined in 11 patients' liver biopsies by atomic absorption spectrometry. RESULTS: 289 MRI studies were available from 115 patients during the period studied. 9.4% of patients had overt diabetes and an additional 16% of patients had impaired fasting glucose. Both pancreatic and cardiac R2* had predictive power (p<0.0001) for identifying diabetes. Cardiac and pancreatic R2* were modestly correlated with one another (r(2) = 0.20, p<0.0001). Both were weakly correlated with LIC (r(2) = 0.09, p<0.0001 for both) and serum ferritin (r(2) = 0.14, p<0.0001 and r(2) = 0.03, p<0.02, respectively). None of the three served as a screening tool for single observations. There is a strong log-log, or power-law, relationship between ratio of signal intensity (SIR) values and pancreas R2* with an r(2) of 0.91. CONCLUSIONS: Pancreatic iron overload can be assessed by MRI, but siderosis in other organs did not correlate significantly with pancreatic hemosiderosis.