The importance of dual-energy computed tomography in the diagnosis of gout, the principles of dual-energy computed tomography, the accuracy of the methodology, and the types of artifacts are discussed in this study. The possible dependence of the presence of deposits of sodium monourate on other clinical data and the role of dual-energy computed tomography in the differential diagnosis of other crystalline arthropathies are considered. The dual-energy computed tomography has several advantages, including noninvasiveness, speed of execution, and a significant reduction in the risk of iatrogenic consequences compared with diagnostic arthrocentesis, which is the gold standard in diagnosing gout. Dual-energy computed tomography can accomplish gout detection, treatment, and differential diagnosis.

Background. The amount of extracellular myocardial matrix is a non-invasive tool for quantitative assessment of myocardial fibrosis. MRI with late gadolinium-enhancement is considered to be the “Gold standard” of non-invasive practice. Dual Energy computed tomography is a new non-invasive approach for detection of myocardial fibrosis and its prognostic value remains unclear. The purpose of this study was to summarize all available data and to study prognostic value of DECT for the detection of fibrotic changes in myocardium.Methods. We searched MEDLINE, EMBASE, Cochrane, SCOPUS and Web of Science for cohort studies up to October 2021 that reported myocardial extracellular volume fraction quantification using contrast enhanced dual energy CT or/and MRI with delayed enhancement.Results. Eleven studies met eligibility criteria. A systematic analysis demonstrated the difference in extracellular volume fraction in patients with fibrotic and inflammation changes of the myocardium, as well as good comparability between DECT and MRI. The value of extracellular volume fraction in myocardium with fibrotic or inflammatory changes was higher than in healthy tissue, which makes it possible to use the ECV as a non-invasive marker of myocardial fibrosis.

Spontaneous pneumomediastinum, pneumothorax, pneumoperitoneum, and soft tissue emphysema have been recently described in several sources as possible complications in patients with severe COVID-19 and lung damage. This clinical case is dedicated to demonstrarte the development of these lesions in 3 male patients with comorbid conditions. The putative pathophysiological mechanism of these complications is air leakage due to extensive diffuse alveolar damage followed by rupture of the alveoli. All presented patients had a favorable outcome of the disease without lethal cases, their laboratory data and clinical dynamics were described.It should be noted that such conditions are not rare complications of COVID-19, and are observed mainly in male patients with severe form of the disease and the presence of comorbid conditions. Such complications are associated with long hospitalization and a severe prognosis. In some cases, with a mild course of the disease and positive dynamics in a decrease of the percentage of pulmonary lesions, the outcome is favorable, not requiring additional invasive interventions.

MSCT is known for its extremely high diagnostic accuracy in coronary artery stenosis detection and quantification. However, there are still questions about physiological assessment of myocardial ischemia, since the degree of arterial stenosis and clinical outcomes do not always correlate. It is also noted that the exclusive use of functional non-invasive tests to assess the grade of stenosis can lead to false-negative results and worsen the long-term prognosis of cardiovascular events. Thus, the combined use of anatomical and functional tests can improve the prognosis in coronary heart disease patient. MSCT coronary angiography, combined with stress perfusion and/or CT derived fractional flow reserve, could be used as an all-in-one approach. This review describes new applications of cardiac MSCT.

Poster: ECR 2021 / C-15284 / Opportunities to reduce radiation exposure during computed tomography (CT) to assess the pathology of the lungs in patients with COVID-19 by: D. Filatova , E. A. Mershina, V. Sinitsyn, M. Plotnikova, D. Bazhenova, V. V. Repyova; Moscow/RU

OBJECTIVE:To reveal diagnostic features in atrial septal defect (ASD) in different age groups; to define a role of X-ray study in the diagnosis of ASD. MATERIAL AND METHODS:Forty-eight patients (16 men and 32 women) aged 15 to 71 years with ASD at different sites were examined. All the patients underwent chest X-ray, echocardiography, and cardiac phase-contrast magnetic resonance imaging (MRI). The examinees were divided into 2 age groups: 1) less than 40 years (n = 18) and 2) more than 40 years (n = 30). The groups were compared using quantitative and alternative signs and they did not significantly differ in the volume of intracardiac shunt and in the size of the defect. The X-ray and MRI indicators reflecting the calibers of pulmonary arteries were also compared in patient groups with different pulmonary artery systolic pressures (PASP) (< 35, 36-60, and > 60 mm Hg). RESULTS:The older age group more frequently showed signs of heart failure, valvular regurgitation, and an atypical X-ray pattern. The sizes of atria, pulmonary artery and its branches, and PASP were also increased in the older age group. The patient group with high PASP (> 60 mm Hg) significantly differed from the others in all the indicators analyzed. Normal PASP and moderate pulmonary hypertension groups greatly differed only in the Moore index. CONCLUSION:Chest X-ray reflects rather precisely the hemodynamic type of the defect. High pulmonary hypertension has clear X-ray and MRI manifestations. The specificity of X-ray in the diagnosis of PASP is lower in the older age group due to the higher rate of an atypical X-ray pattern. Radiology is important in detecting pulmonary venous hypertension in patients with PASP. Pulmonary venous hypertension is indicative of elevated pressure in the left atrium and pulmonary veins and arises from different causes: shunt inversion, restrictive defect, mitral valve comorbidity, and left ventricular systolic and diastolic dysfunction.

OBJECTIVE:To estimate the contribution of dual-energy computed tomographic (CT angiopulmonography t o a diagnostic algorithm in patients with chronic thromboembolic pulmonary hypertension (CTEPH) and its role in the evaluation of postoperative changes.MATERIAL AND METHODS:CT angiopulmonography was performed on the 64-slice Discovery HD 750 system (GE Healthcare) using the dual-energy scanning mode (140 and 80 kV). The examination results in patients with CTEPH were analyzed.RESULTS:All the patients were found to have typical CT signs of CTEPH: abnormal contrast enhancement of the pulmonary arteries, their dilatation and tortuosity; signs of right cardiac overload: right ventricular dilatation and/or hypertrophy, bronchial artery dilatation, decreased peripheral vascular pattern, mosaic pulmonary perfusion, and wedge-shaped perfusion defects on the iodine maps. Mosaic pulmonary perfusion areas were also found in all the patients. Perfusion defects were more clearly visualized when dual-energy CT by constructing iodine perfusion maps was used. Analyzing the perfusion maps in 6 patients operated on revealed a 20-50% reduction in perfusion deficit.CONCLUSION:Information on the vascular bed and pulmonary perfusion may be obtained in patients with CTEPH within one investigation, which is important to plan surgical treatment. Construction of iodine pulmonary perfusion maps allows evaluation of perfusion recovery after artery thromboendarterectomy.

Poster: "ECR 2011 / C-2141 / Dual-energy pulmonary CT-angiography (DEPCTA) before and after pulmonary endarterectomy" by: "E. A. Mershina, V. Sinitsyn, E. D. Akchurina, M. Plotnikova, Y. Frolova; Moscow/RU"