Objective: to investigate the possibilities of a combined single photon emission computed tomography/computed tomography (SPECT/CT) system during myocardial perfusion studies and to examine the features of their interpretation.

Subjects and methods. In April 2013 to April 2019, the Department of Radionuclide Diagnosis, National Medical Research Center of Cardiology, performed myocardial perfusion SPECT with attenuation correction (AC) in 3144 patients with various cardiovascular diseases. Based on the experience gained, the authors expanded and adjusted the principles of processing and interpreting the results of this study, which they had first set forth in 2014. Special emphasis is placed on the interpretation of apical and septal perfusion defects and diffuse perfusion irregularity, on the demonstration of the role of current reconstruction algorithms in obtaining highest-quality myocardial images, and on the assessment of self-potentialities of lowdose CT findings at myocardial SPECT/CT, as well as on proposals to standardize quantitative parameters for perfusion assessment at myocardial SPECT/CT.

Results. AC affected in large measure the interpretation of myocardial perfusion SPECT in most cases. Apical perfusion defect appeared on AC images was observed in 50% of patients without established coronary heart disease and could be interpreted as a normal variant (apical thinning). The diffuse irregularity of perfusion radiopharmaceutical tracer accumulation in the application of the current reconstruction algorithms stood out in a separate pattern as a sign of microcirculatory disturbances. Low-dose CT data allow visualization of a severe thoracic abnormality at imaging and should be reflected in the conclusion. The perfusion study descriptions based on an analysis of AC and nAC images had a greater interoperator consistency than those based on an analysis of only nAC images (w = 0.915 and 0.809, respectively; p = 0.027). At the same time, the use of arithmetic means of the extent of transient ischemia (Reversibility Extent) is better consistent with visual analysis (= 0.08Ѓ}1.46%, p = 0.49).

Objective: to compare the quality of residual colonic content tagging with 25 and 50 g of BAR-VIPS, the basе of which is barium sulfate (BaSO4), in preparing patients for virtual colonoscopy (VСS) and to evaluate the diagnostic efficiency of the method in both cases.

Material and methods. The paper presents the results of VCS in 100 patients divided into two groups containing equal numbers (n = 50) according to the contrast medium dose (25 and 50 g). In each group, the quality of fecal tagging (FT) was compared by its presence and degree and by the presence and completeness of high-density artifacts for residual liquid and solid fragments separately. The reliability of the results of VCS versus fibrocolonoscopy was assessed in detecting additional colon tumors of three sizes (<6, 6-9, and ≥10 mm) in each group of patients. These results were used to calculate the diagnostic efficiency of VCS in each group.

Results. The investigation showed significantly lower FT quality indicators in the patients using 25 g of BAR-VIPS than in those having 50 g of the same agent (p = 0.00001). Naturally to the quality of FT, all VCS information capability indices for all sizes of colonic tumors were lower in the 25-g group than those in 50g group.

Conclusion. The option of preparing patients for VCS using residual colonic content tagging with 50 g of barium-containing BAR-VIPS has been found to have a significant advantage over that using 2 g of the same agent. This is shown in the better quality of FT and in the higher diagnostic efficiency of the method.

Objective: to reveal a relationship of lung changes to time after radiotherapy (RT), its dose, and irradiated volume, by using a new procedure to quantitatively evaluate lung tissue density changes according to the data of dynamic X-ray computed tomography (X-ray CT) imaging.

Subjects and methods. Data on 29 cancer patients who had received RT to the chest area using 3D planning, 2-5-Gy fractions, and a total focal RT dose of 16 to 84 Gy in the lung tissue were retrospectively selected. Each patient underwent at least two X-ray CT studies (before and after RT); a total of 83 studies were analyzed. The new diagnostic procedure developed by the authors was used to quantitatively analyze lung tissue density changes in the areas with a selected dose range.

Results. On days 1 to 15-30 after completion of RT, the quantitative analysis revealed no significant density changes. On days 70-80, there was an increase in changes that were different from those in the nonirradiated areas. On 80 to 100-120 days, there was a decline of radiation reactions with preserved changes in the areas irradiated at a dose of 19-20 Gy. From 120 days onwards, the changes were preserved in the areas irradiated at a dose of over 32-37 Gy through the formation of post-radiation pulmonary fibrosis. In addition, eight (27.6%) patients treated with less than 20 Gy were detected to have changes associated with the initial density values, which can be regarded as an increased individual radiosensitivity.

Conclusion. The time course of a quantitative change in the median lung tissue density in the areas irradiated at different doses allows radiation-induced lung injury to be detected at X-ray CT until the visual signs of pneumonitis appear. A continuous, quantitative scale of changes will assist in more reliably and accurately studying post-radiation changes at a later time, and the time course of spaciotemporal changes will be able to compare and quantify lung injury when exploring new treatment methods and policies.

Objective: to analyze the diagnostic value of radiation techniques in patients with opisthorchiasis-induced obstructive jaundice and to determine the types of bile duct (BD) changes characteristic of this disease.

Subjects and methods. The investigation enrolled 103 patients with chronic opisthorchiasis complicated by obstructive jaundice. For BD visualization, the investigators used radiation diagnostic methods, such as ultrasonography (USG), magnetic resonance cholangiopancreatography (MRCP), and endoscopic retrograde cholangiopancreatography (ERCP); their efficiency was evaluated.

Results. ERCP and MRCP could identify 5 types of BD architectonics in opisthorchiasis-induced obstructive jaundice. The sensitivity, specificity, and overall accuracy of MRCP in diagnosing opisthorchiasis-induced sclerotic changes were 98.1, 87.5, and 96.8%, respectively.

Conclusion. Among instrumental methods for diagnosing sclerotic BD changes in prolonged opisthorchiasis invasion, it is preferable to use MRCP, which is determined by its high informative value. Five types of cholangioarchitectonics are detectable in chronic opisthorchiasis complicated by obstructive jaundice.

The observation reveals the diagnostic capabilities of computed tomography to address issues arising in the implementation of forensic medical examinations. It considers a case of computed tomography used to determine the nature of brain injury in a 1-month-old baby. Cranial injuries detected by computed tomography had characteristic signs indicating the compression mechanism of causing brain injury. An interdisciplinary approach made it possible to exclude causes for a child's head injuries resulting from a fall.

The paper describes a clinical case of multistep treatment for coronary heart disease in a patient with diffuse coronary arterial involvement after multiple stenting. The feature of the given paper is successful restenting of the anterior descending artery in the stent endarterectomy area after coronary artery bypass grafting.

With allowance made for the widespread prevalence of diffuse liver diseases, non-alcoholic fatty liver disease in particular, there is a need for the most objective evaluation of the state of this organ. One of the most important criteria for this evaluation is to estimate liver tissue density values. Today, the introduction of programs, such as lung cancer screening using low-dose computed tomography, has made it possible to conduct mass surveys in this area. This literature review deals with the advantages and disadvantages of computed tomography in detecting diffuse liver lesions.