External beam radiation therapy (EBRT) is currently an important component of the treatment of gastric cancer (GC). In accordance with international and domestic recommendations, it can be used in the postoperative period, before the operation and as a sole option, with a curative and palliative purpose, usually in combination with chemotherapy. With the transition of RT to a new technological level, which involves the use of conformal, intensively modulated regimens, and image guidance the revision of indications for and doses of EBRT is required. The article discusses modern approaches to the determination of irradiated volumes in various clinical scenarios of current radiation therapy for GC and strategies aimed at reducing the dose in critical organs at risk and increasing the overall effectiveness of treatment.

Vertigo and dizziness are among the most common complaints prompting a large number of imaging investigations. Causes of central and peripheral vertigo are very diverse but some of them present with typical imaging findings. In this paper we review a number of etiologies of vertigo and describe relevant CT and MR imaging findings.

Differential diagnostics of non-traumatic intracerebral hemorrhages is a critical area of scientific research and development in neuroradiology. In modern clinical practice, diagnostics are often limited to anatomical description of pathology without taking into account its etiology and pathogenesis. This paper analyzes the ethiopathogenetic factors underlying non-traumatic intracranial hemorrhages, as well as the potential of tomography in differential diagnosis of intracerebral non-traumatic hemorrhages with regard to localization and prevalence. Additionally, the paper analyzes the most common misinterpretations in the diagnostics of non-traumatic intracerebral hemorrhages, providing examples of pathologies with different etiologic but similar hallmarks in magnetic resonance imaging (MRI) and computed tomography (CT).

This review presents current information on the diagnosis of patients with pathology of the ascending aorta in the pre and postoperative period using multispiral computed tomography. The authors paid attention to the importance of valuation of the valvular apparatus elements, the geometry of the root of the aorta (effective coaptation height, Henle triangles, aortic regurgitation area, etc.), the features of which are necessary for the surgeon to solve technical issues of the forthcoming operation. A comparison of the diagnostic value of multispiral computed tomography and transthoracic echocardiography with respect to the visualization of valvular structures is shown. The role of multispiral computed tomography in the planning of transcatheter aortic valve replacement and the determination of results after intervention is described. With the help of multispiral computed tomography, assessing the state of the ascending aorta, the aortic root and aortic valve elements, the surgeon has an opportunity to choose the optimal variant of the valve-preserving operation and to evaluate postoperative results in the preoperative period.

Objective: to determine the role of magnetic resonance imaging (MRI) in the pathomorphological evaluation of focal changes in the central nervous system (CNS) of fetuses with hemolytic disease before and after treatment, by intrauterine intravascular blood transfusion, and to compare the MRI data of fetuses with ultrasound neurosonography (NSH) newborns. The study included 45 pregnant women and their 45 newborns. Patients are divided into 2 groups. The main group: 30 pregnant women (mean gestation period 32,1 weeks) with hemolytic disease of the fetus who underwent intrauterine intravascular blood transfusion and their 30 newborns with hemolytic disease of the newborn. In this group, comparative MRI examinations of the central nervous system were performed using a protocol including fast MP sequences based on T1 and T2-weighted images, as well as the DWI pulse sequence, both before treatment (intrauterine intravascular blood transfusion of the fetus), and after treatment (regardless of the multiplicity of intrauterine intravascular transfusion — before delivery). The comparison group comprised 15 pregnant women (mean gestation period of 38,6 weeks) with no signs of hemolytic disease, examined by MRI for other indications (concomitant pathology of pregnancy) and their 15 newborns, comparable in gestational age to the main group. The obstetric anamnesis, the MRI data of the central nervous system of fetuses before the treatment (the first intrauterine intravascular transfusion) and after the treatment (before the delivery) and the results of ultrasound for the first day of life were analyzed. When comparing the MRI data of changes in the central nervous system, in the main group (in fetuses with bladder) in relation to the comparison group before treatment (the first intrauterine, intravascular transfusion), a high incidence of focal changes in the brain substance in the main group was revealed. The use of MRIdiagnostics demonstrates a decrease in the risk of development of PCNC in ischemic type, in dynamics before and after treatment. Based on the MRI diagnostic data of the fetal CNS, it is possible to judge the prognosis of the outcomes of hemolytic disease of the fetus, in comparison with the neonatal neurosonography data for the first day.

Nowadays of great importance is not only the issue of early diagnosis of HIV infection, but of early detection and effective treatment of AIDS complications. The annual increase in the incidence of HIV infection amounts to 4%. Unfortunately, a great number of patients ask for hospital care when their disease has the stage of secondary complications. Such situation requires a fast and affordable diagnostics together with verification of the nature of the affection. Purpose. To evaluate the diagnosis effectiveness of the secondary infectious cerebral affection in patients with HIV infection using the method of non-contrast MRI including the usage of the specially developed software. One hundred thirty three patients were recruited for the study, the main group of 108 persons (as old as 36,8±8,3), all referred to the brain MRI with suggestion of neurologic complications of HIV. The control group comprised 25 patients of the same age with focal damage of vascular nature. In everybody the MRI has been carried out using open middle-field scanner (Az-360, by AZ plc company, Moscow) with field induction 0,4 T, supplied with wireless four-channel quadratur coil for head studies, without contrast enhancement, but using in everybody the specially designed protocols for compensation of movement artifacts. All patients were re-examined in 2, 4 and 6 weeks. MRI images both in first admission and in follow-up studies were reported first qualitatively by type of contour of pathologic focus, by presence of multiple pattern of focal damage, by ultrastructure of foci, extent of perifocal oedema, interhaemispheric dislocation; also the dimensions of lateral ventriculi, of external subarachnoidal spaces and thickness of cortex in various regions were measured. Focal cerebral damage verified later as toxoplasmosis was revealed in the main group in 80% (86 of 108) of patients. False-negative and false-positive conclusions of MRI studies were not revealed also in prospective follow-up studies. Of these in 69 (80,2%) the pathologic foci were multiple and did localize periventricularly in particular in putamen, nucleus caudatus, equally frequent for both haemispherae, single foci were detected in thalami, concomitant with tendency to extensive cortical dystrophy. The putamen region was involved more frequently as compared to other basal ganglii (р=0,003). No significant differences were revealed between various cortical regions as regard to frequency of detection of pathologic foci. Four weeks period was detected as being the most effective time for the dynamic control in the course of treatment. Conclusion. Middle-field MRI of the brain with compensation of movement artifacts is a proper technique for both the diagnosis and follow-up control of treatment of cerebral toxoplasmosis in patients with HIV infection.

Data of 130 patients with thunderclap headache are presented. The data include clinical manifestation analysis and neuroimaging results (magnetic resonance angiography). Magnetic resonance angiography was performed 15 days after acute clinical manifestation and permitted to verify cerebral vasoconstriction, that led to treatment modification with clinical and neuroimaging signs of vasoconstriction reverse.

In the article possibilities of radionuclide methods of research are shown in prognostication of heart failure and estimation of efficiency of restoration treatment for patients, carrying the heart attack of myocardium.

In the century of the fourth industrial revolution, there is a rapid progress of technological developments in medicine. Possibilities of collecting large amounts of digital information and the modern computer capacity growth are reasons for the increased attention to artificial intelligence (AI) and its role in the diagnostics and the prediction of diseases. In the diagnostics, AI aims to model the human intellectual activity, providing assistance to a practicing doctor in the processing of big data. Development of AI can be considered as a way for implementation and ensuring of national political and economic interests in the health care improvement. Lung cancer is on the first position of cancer incidences. This implies that the development and implementation of computed-aided systems for lung cancer diagnostic is very urgent and important. The article presents the results concerning the development of a computed-aided system for the lung nodule detection, which is based on the processing of computed tomography data. Perspectives of the AI application to the lung cancer diagnostics are discussed. There is a few information about a role of Russian developments in this area in foreign and domestic literature.

MRT with dynamic contrast enhancement has not found wide application in lung pathology, there are no clear recommendations for its implementation, no criteria for the goodness of the changes have been developed. The aim: of the study was to clarify the procedure for analyzing the data of DKU-MRI, the search for predictors of the quality of focal changes in the lungs. DKE-MRT performed 28 patients with verified benign changes in the lungs at a magnetic resonance tomograph of 1,5 T. As the analysis shows, the use of relative rather than absolute values with the calculation of the contrast index (CI), reflecting the degree of accumulation of a paramagnetic substance in the object of investigation relative to the main anatomical landmark-aorta, is a reliable sign of angiogenesis. In this case, it is necessary to focus on the zones of maximum intensity of the MR signal of the structure under study, the value of ROI can vary considerably. The CI in the hamartomas was 0,23–0,35. In the scar tissue, the CI values did not practically change throughout the study, being 0,21–0,25 relative to the peak density in the aorta. CI soft tissues and benign focal lesions of the lungs, the form of the curve of the paramagnetic circulation was comparable, being 0,25–0,3 relative to the peak density to the aorta. When analyzing the DKE-MRT curves, the concentration/time should be oriented to the zones of maximum intensity of the MR signal from vascular structures, focal lesions of the lungs, soft tissues of the back, while the ROI area is of no fundamental importance. As a criterion of good-quality focal formation of the lung should be guided by CI in soft tissues.

Objective: to study the possibilities of Choi criteria in evaluating the objective response of metastatic colorectal cancer to transarterial chemoembolization (TACE), as well as to study the influence of the size and density of metastatic lesions on the posttreatment prognosis of the disease. Material and methods. CT data of 78 patients with colorectal cancer metastatic liver lesions before and after TACE with drug-eluted microspheres was analyzed. The posttreatment changes in the size and density of lesions were statistically analyzed. Evaluation of the treatment results was made according to Choi criteria and according to RECIST criteria. The effectiveness of both criteria was compared by analyzing progression-free survival (PFS) using the Kaplan-Meier method. The analysis of the influence of pretreatment size and density of lesions on the time to progression was done. Results. There was no significant reduction in the size of the liber lesions after TACE, but the density of the lesions decreased. According to the RECIST criteria, the stable disease was established in the majority of patients (73,1%). According to the Choi criteria, the majority of patients (65,4%) had a partial response. Response category coincided in 37,1% of observations. There were no significant differences in PFS between patients with different response categories according to RECIST criteria (p=0,052). PFS in patients with different response categories according to Choi criteria was different (p=0,000). There were no significant differences in PFS between patients with different sizes of foci before treatment (p=0,833). A higher density of foci before treatment provides higher PFS values (p=0,001). The sizes of lesions remain stable after TACE, but their density decreases. The Choi criteria are more effective in evaluating the TACE results of colorectal liver metastases than the RECIST criteria. The pretreatment lesions size is not a prognostic factor. Higher initial lesions density is associated with better treatment prognosis.

Cystic adventitial disease (CAD) is a rare cause of unilateral intermittent claudication of unknown aetiology, which is characterized by the formation of multiple mucin-filled cysts in the adventitial layer of the arterial wall resulting in obstruction to blood flow. The disease predominantly presents in young otherwise healthy males and most commonly affects the popliteal artery (85% of cases). CAD can be diagnosed by duplex ultrasound, magnetic resonance imaging, magnetic resonance angiography, or computed tomographic angiography. Surgery is the primary mode of treatment, including exarterectomy, or replacement of the affected vascular segment by venous or synthetic interposition graft. Alternatively, the cysts can be drained by percutaneous ultrasound-guided needle aspiration. We conducted a review of the literature on the aetiology, diagnosis and treatment of this uncommon condition and present the case report.

Risk management practice becomes an integral part of the management system of the medical institution. The deployment of risk management system contributes to the sustainable development of the organization by enhancing the decision making process and ensuring a balance between risks and opportunities. The risk management tools within the approaches of COSO, ISO and JCI standards, which, from the author’s point of view, can be effective for the management of typical risks of a medical diagnostic institution, are considered in the article.

The Komi Republic is a region with a low population density. The radiology service in the republic is provided by121 general radiologists and 78 ultrasound diagnosis specialists. Thus, the staffing level of radiologists and ultrasound specialists is significantly lower comparing to the rest of the Russian Federation. Structure of radiology examsin Republic almost coincides with the rest of the Russian Federation: the first place take ultrasound examinations —53,2% (Russia — 56,8%), the second place takes plane film radiology — 40,8% (Russia — 39%), the third — computed tomography — 5% (Russia – 3,3%), magnetic resonance imaging is in fourth place — 1% (Russia – 0,9%).The optimal modes of low-dose computed tomography of the chest are identified with an average effective dose of0,575±0,160 millisievert (mSv) with minimal loss of quality. Digital mammography, ultrasound elastography andintroduction of the Bi-RADS scale, as well as digital fluorography and introduction of low-dose computed tomography of the chest to the annual preventive examination of the population at risk of lung cancer are considered as priority areas in improving the quality of early cancer diagnosis among the population of the republic. The radiologicalsociety of Komi Republic was created with 61% (123) radiologists as members. Respectively, the main objectives forthe radiology in the Republic of Komi for 2018–2019 are: increased availability of perfusion methods of acute andchronic cerebral ischemia diagnosis, implementation of the pilot project «Low-dose computed tomography organs ofthe chest», increasing the availability of magnetic resonance tomography in pediatric practice, implementation anddevelopment of telemedicine technologies in the Komi Republic and continuous advanced training of radiologists,development and improving the activities of the Komi Republican Radiological society.