Summary. One of the promising neuroimaging methods for studying the brain in cerebrovascular disease is MRI perfusion of the brain. It is of interest to compare the revealed data with the results of specialized neuropsychological testing in individuals with chronic cerebral ischemia, including patients from the risk group – exposed to radiation.

Objective of the study: 165 patients aged 55 to 87 years diagnosed with chronic cerebrovascular disease were examined. The main group included 97 liquidators of the Chernobyl accident (LPA), the control group included 68 patients who were not exposed to radiation. Perfusion changes (CBV and CBF) in the gray and white matter of the right frontal lobe (ROI-1, ROI-2) and similarly in the left hemisphere (ROI-4, ROI-5) were assessed. The obtained perfusion data were then compared with the results of neuropsychological testing. Results: Сomparing the MRI perfusion parameters (CBV in ml/100 g and CBF in ml/100 g/min), a statistically significant decrease in the specified parameters was found in ROI-1 (CBV, p = 0.010; CBF, p = 0.011) and ROI-4 (CBV, p = 0.009; CBF, p = 0.001), mainly in the main group. Analysis of the neuropsychological testing results revealed a statistically significant (p = 0.005) decrease in MMSE and MoCA in the main group compared to the control group. In addition, the HADS results demonstrated a significant increase in values ​​in the main group, both in the anxiety section (p = 0.024) and in the depression section (p = 0.027) in relation to the control group. Correlation analysis between CBV and CBF in ROI-1, ROI-2, ROI-3, ROI-4 and ROI-5 in accordance with the anatomical landmarks of the brain at the level of the lateral ventricles according to MRI perfusion data and the results of neuropsychological testing revealed statistically significant direct correlations between CBF/CBV in ROI-1/ROI-4 and MMSE, MoCA and HADS.

Conclusions. MRI perfusion revealed more pronounced disturbances in perfusion parameters in LPA compared to the control group, and correlation analysis between CBV/CBF and the results of neuropsychological testing established a direct relationship between the clinical manifestations of the psychopathological syndrome, expressed in a decrease in cognitive functions with the severity of neurovascular deficit in patients of the main group with systemic endothelial dysfunction due to man-made irradiation of the whole body in the late period. The obtained data demonstrate and confirm the effectiveness of contrast T2*-perfusion and can be used as neuroimaging biomarkers in individuals with cerebrovascular disease.

Abstract. This study aimed to test the method of fast molecular proton fraction mapping as a tool for quantitative assessment of myelin deficiency in affective disorders between general and local measurements in seven selected regions of interest of both hemispheres in comparison with the control group, determining the sensitivity and specificity of the method.

Materials and methods. The study included 24 patients with affective disorders, 13 were diagnosed with a current depressive episode as part of recurrent depressive disorder, and 11 were diagnosed with bipolar affective disorder. All patients underwent non-contrast magnetic resonance imaging of the brain using a fast MPF mapping protocol. Comparison of the MPF levels for the control and experimental groups were calculated using the Mann-Whitney U-test. ROC analysis was used to assess the prognostic value of the investigating parameters.

Results. The average MPF indices of all selected regions of interest for the control group and group of patients with affective disorders (AD) were significantly different (p < 0.0001). In a pairwise comparison of each selected area, patients with AD showed a significant decrease in MPF in all selected areas of white matter compared to the control group (p < 0.05). Analyzing the ROC curves, the largest areas under the ROC curves (AUC) were 0.892 ± 0.061 (83.3%; 88.89%) and 0.888 ± 0.054 (70.83%; 83.3%) in the periventricular zone and thalamic area respectively. which indicates the “high” information content of these models for detecting the process of hypomyelination in patients with AR.

Conclusion. Affective disorders are characterized by a significant decrease in the MPF of the white matter of the brain in comparison with the control group (p < 0.05), which indicates a decrease in the concentration of myelin in the observed areas. The process of hypomyelination is diffuse as it was significantly expressed in all selected regions of interest in patients with affective disorders, including the periventricular zone and the area of thalamus and basal ganglia in comparison with controls (p < 0.05). MPF changes in the periventricular zone have the greatest diagnostic value for detecting hypomyelination in AD (PPV = 91%, NPV = 80%).

Safe follow-up and assessment of early changes in ocular hemodynamics in young patients with type 1 diabetes mellitus is of paramount importance. Doppler ultrasound is widely used in ophthalmology to assess the blood supply to the eyeball and orbit. The method is accessible, safe, painless, and can be used for dynamic monitoring of changes in the hemodynamics of the eye and orbit in children and adolescents with type 1 diabetes mellitus.

Objective: to develop an ultrasound scale for a comprehensive assessment of changes in retrobulbar blood flow in patients with type 1 diabetes mellitus in childhood and adolescence.

Materials and methods. The study included data from 223 children aged 7–18 years, 173 children with type 1 diabetes, and a control group – 50 children. The analysis took into account ultrasound indicators in b-mode, Doppler mode, and ophthalmoscopy data.

The results obtained from the study report the possibilities of using the Oph-RADS ultrasound scale for a comprehensive assessment of retrobulbar blood flow in patients with type 1 diabetes mellitus at a young age.

Background: one of the most pressing problems of ultrasound shear wave elastometry of the liver is the lack of distinct digital differential diagnostic criteria for the presence and severity of fibrosis in inflammation.

Purpose. To evaluate the possibility of a new ultrasonic parameter – the shear wave dispersion slope (SWDS) in solving this problem.

Materials and methods. 156 patients with various liver pathologies were examined. Depending on the absence or presence of fibrosis, as well as inflammatory changes in the liver (according to biopsy and serological blood tests), the examined patients were divided into three groups. The control group consisted of 10 healthy donors. Measurements of the shear wave velocity (SWS), shear wave dispersion slope (SWDS) and the assessment of ultrasound attenuation (ATI) in the liver were performed using the Canon Medical Aplio i800 ultrasound diagnostic system (Tokyo, Japan) using a standard convex transducer.

Results. The indicators of SWS, SWDS and ATI (Median and 95% CI) in the control group were Me 1.2 (95% CI 1.1–1.6) m/s, Me 10.1 (95% CI 9.7–14.3) m/s/kHz and Me 0.54 (95% CI 0.41–0.63) dB/cm/MHz, respectively. The study of the main group showed that there is a close correlation between SWS and SWDS (Spearman's rho = 0.74). At the same time, patients in the subgroup with inflammation had significantly (p < 0.01) higher SWDS values compared with the control group and the subgroup without inflammation – Me 16.4 (95% CI 15.3–17.9) m/s/kHz versus Me 10.1 (95% CI 9.7–14.3) m/s/kHz and Me 12.7 (95%CI 12.1–14.3) m/s/kHz. In patients of the subgroup with fibrosis, but without inflammation, there was also a significant (p < 0.01) increase in SWDS from Me 12,0 (95% CI 11.4–12.8) m/s/kHz at F0-1 to Me 16,5 (95% CI 12.9–20.3) m/s/kHz at F3–4 METAVIR.

Conclusion. The use of absolute SWDS values did not contribute to the achievement of the purpose of this study – the detection of criteria for the differential diagnosis of the presence and severity of liver fibrosis in patients with hepatitis. Nevertheless, the results of the study provide grounds for making a fairly confident conclusion that the assessment of the relationship between SWDS and SWS using the binary logistic regression formula (logit(p) = 0, 4152 SWDS (м/с/кГц) – 0,1344 SWS (м/с) – 6,5115) can become a valuable additional method for ultrasound diagnostics of inflammatory changes in the liver.

Relevance. Modern studies focus on the analysis of hemodynamic changes in the liver in diffuse pathologies, as well as the role of mechanisms that increase arterial perfusion with a decrease in portal blood flow. Diffuse liver diseases eventually lead to fibrosis and the risk of cirrhosis, but invasive biopsy remains the only accurate method for staging. Non-invasive methods such as elastography and the Child–Pugh scale help assess the severity of liver cirrhosis. Perfusion CT (PCT) allows you to determine the functional state of hepatocytes and determine their microcirculation. The method is safe, has a high resolution and provides complex parameters of liver perfusion. Wide-detector CT allows you to level out various artifacts, obtain perfusion images of the liver in a single scan and expand the diagnostic capabilities of this technique.

The aim: to evaluate the diagnostic effectiveness of volumetric perfusion CT in determining the severity of hemodynamic disorders in patients with portal hypertension (PH), taking into account the level of blockage of the portal circulation.

Materials and methods.The prospective study involved 110 patients divided into four groups: 63 patients with liver cirrhosis (LC) (block at the level of the intrahepatic postsinusoidal circulation); 10 patients with liver fibrosis (LF) (block at the level of intrahepatic presinusoidal circulation); 13 patients with PH of extrahepatic etiology (block at the level of the subhepatic circulation), 24 patients in the control group, donors of the liver fragment. The study assessed liver perfusion parameters such as arterial perfusion (AP), portal perfusion (PP) and hepatic perfusion index (HPI).

Results. The most pronounced deviations in liver perfusion were verified in subhepatic block (SHB), with a significant increase in the liver index (35.6 ± 1.5%; p < 0.001). In cirrhosis with postsinusoidal block, there was a significant decrease in the portal fraction, a compensatory increase in arterial blood flow to 41.4 ± 0.7 ml/100 ml/min and, accordingly, a higher increase in the liver index (23.8 ± 0.4%; p < 0.001). Paradoxical changes in perfusion parameters with the formation of a hyperkinetic type of blood circulation and an increase in portal blood flow relative to normative values up to 169.4 ± 5.0 ml/100 ml/min (p < 0.01) were obtained in AF.

Conclusion. The results confirm the diagnostic effectiveness of volumetric CT perfusion and its significance in assessing and predicting the severity of hemodynamic disorders in patients, taking into account the level of blockage of the portal circulation.

Objective: To evaluate the diagnostic capabilities of detecting metastatic lesions on post-contrast images using magnetization transfer contrast with a short fat-suppressed presaturation pulse.

Materials and methods. The study material consisted of dynamic contrast-enhanced MR images of abdominal organs with metastatic liver involvement. Parameters of the pre-saturation pulse: Δf = -210 Hz, FA = 600°. Contrast ratio (CR) was calculated for each focus using a formula: CR = ((I_FOCUS – I_LIVER) / I_LIVER) • 100%. Vascularization was assessed on a scale of 3 categories: hypovascular, isovascular, and hypervascular. Threshold values for each category were calculated using cluster analysis. To assess the sensitivity of focus detection, they were divided into groups by size: Group 1 − from 5 mm to 10 mm; Group 2 − from 10 mm to 20 mm. Statistical analysis of the results was performed using the Mann-Whitney, Wilcoxon, Cochran, and McNemar criteria.

Results. In the course of the clinical study, heterogeneous groups of patients were obtained in terms of gender and age depending on the nature of vascularization of liver foci during analysis of the arterial phase of DCE: hypervascular (n = 14) and hypovascular (n = 38), with a total of 52 studies conducted, as one patient had dynamic control. The threshold value for the group of hypervascular metastases was identified as CR > 49.6%. In Group 1 (5 mm to 10 mm), the sensitivity of detecting foci on post-contrast images T-TSE-MTC was 47.7%. In Group 2, there were no statistically significant differences between the diagnosis of foci sized 10 mm or larger on post-contrast images T1-TSE-MTC and all phases of DCE (p < 0.0001), with a sensitivity of 100%.

Conclusions. 1. According to cluster analysis, T1-weighted study based on fast spin echo with magnetization transfer contrast (T1-TSE-MTC) allows differentiation of hypervascular metastases from transitional and hypovascular (p < 0.05).

1. The contrast of hypervascular metastases in the post-contrast phase on T1-TSE-MTC images does not significantly differ from the arterial phase of dynamic contrast enhancement (DCE) (p > 0.05).
2. A high sensitivity to enhancement by paramagnetics at low concentrations on T1-TSE-MTC images was revealed, which reduces the contrast of hypovascular metastatic foci sized 5 to 10 mm with a significant decrease in their detection compared to DCE (p < 0.05), while for sizes 10 to 20 mm, no significant differences with DCE were found (p > 0.05).

Purpose. Determination of the possibility of using kidney segmentation to obtain data on their volume and density characteristics to assess the split renal function.

Material and methods. The data of 31 patients who underwent nephroscintigraphy and CT examination of the kidneys with contrast were analyzed. Segmentation of both kidneys into the nephrographic phase of contrast was performed at the workstation using the Vitrea Advanced Visualization program. The obtained values of the volume were multiplied at the attenuation coefficient of X-ray radiation in Hounsfield units (HU) for each kidney to obtain the "mass" of the contrast preparation. Having divided the obtained value of each kidney by their sum value and multiplying by 100%, we obtained a split contribution of each kidney to their total excretory function in percentages. To verify the need to introduce parenchymal density into calculations in the native phase of the study, the density of the parenchyma of both kidneys was measured at three levels in the native phase, then, the calculated arithmetic mean was subtracted from the average density of the renal parenchyma in the nephrographic phase. Subsequently, the same calculations were performed to obtain the percentage contribution of the kidneys as before deducting the native density. Nephroscintigraphy was performed in various medical institutions. Studies were conducted with technetium compounds (99mTc). For further analysis, data on the percentage contribution of each kidney to their overall excretory function were taken.

Results. The obtained data on the percentage contribution of the kidneys to their total excretory function obtained by nephroscintigraphy were compared with the calculated CT data. The analysis showed a very high correlation and covariance of these results (the correlation coefficient is 0.99 (p < 0.001), the covariance coefficient is 0.95 (p < 0.001)). When conducting a correlation analysis of the results of nephroscintigraphy with CT data, where an additional correction was made for the native density of parenchyma (it was subtracted from the average density of parenchyma in the nephrographic phase), the results remained the same: the correlation coefficient was 0.99 (p < 0.001); the covariance coefficient was 0.95 (p < 0.001).

Conclusions. An accessible and practical method for evaluating split renal function has been developed. The method does not require the implementation of a clearly regulated time protocol for multiphase CT. CT data performed in any medical institution can be evaluated. The method does not require additional assessment of the native densitometric characteristics of the kidneys. The results obtained using the method showed a very high correlation with the data of dynamic nephroscintigraphy.

Aim: analysis of literature sources and comparative evaluation of research results on the effectiveness of performing renal elastography in almost healthy patients, development of stiffness standards for kidneys in practically healthy patients and development of a standard technology for performing the study.

Material and methods. A search was conducted for scientific articles, publications, clinical recommendations, reports of congresses in the information and analytical systems eLibrary, Google Scholar and PubMed for 2013–2024 by keywords: kidney elastography, assessment of kidney stiffness, ultrasound elastography of the kidneys, renal elastography, renal stiffness. The analysis of the literature lists of the found articles according to the relevant criteria was also carried out.

Results. According to the relevant keywords, 288 articles were selected, including publications of scientific congresses and conferences, 39 articles were recognized by the authors as corresponding to the subject of the scientific review. And 8 additional articles were selected from the literature lists of the found articles. As a result of the search, a group of articles was created among which the material was analyzed to get answers to the questions posed.

Conclusion. The analysis of the literature data is one of the stages of systematization of previously conducted studies in the field of renal elasticity and allows us to note the importance of excluding all factors described by previous authors that cause significant variability in the stiffness of unchanged renal parenchyma. As a result of the review, the authors showed the possibility of using 2D shear wave ultrasound elastography in assessing the stiffness of the renal parenchyma by a non-invasive method and the need to develop a standard research methodology that minimizes the error.

Aim: to develop the module of automated calcification identification (MACI) capable to mark the different types of breast calcifications and suitable for incorporation into the computer-aided detection (CAD) system for mammography, as well as to assess its clinical efficiency.

Material and methods. We performed prospective, randomized study included 9078 women who underwent the mammography. All the subjects were randomized (1:1) into the control (CAD) and experimental (CAD + MACI) arms. In the CAD arm the mammography images were processed with the help of CAD MammCheck (with no MACI). In the CAD + MACI arm we used the combined CAD and MACI image processing. After the primary screening completion the subjects were followed for minimum 3 years.

Results. During the visual mammography image analysis in the CAD + MACI и CAD arms 170 (3.74%) и 159 (3.50%; р = 0.3716) breast carcinoma (BC) cases were proven, respectively. After the CAD markings analysis we additionally proven 10 and 6 BC cases, respectively (р = 0.8175). During the subsequent MACI markings analysis in the CAD + MACI arm 7 (0.15%) BC cases were verified. Totally, during the primary screening we found 187 and 165 BC cases, respectively (р = 0.0477). During the 3-year follow-up in the CAD + MACI arm 16 BC cases were proven (0.35%), of them in 2 (0.04%) cases the microcalcifications were found in the area of the subsequently verified BC. In the CAD arm the corresponding values were 22 (0.48%) and 9 (0.20%) BC cases (р = 0.054).

Conclusion. MACI incorporation into the CAD design significantly increases (5.81%) the detection rate of BC associated with microcalcifications at the expense of small (0.89%) increase of the recall rate.

Objective: to develop a convolutional neural network (CNN) model to classify the presence and severity of central lumbar spinal stenosis (LSS) during MRI examination and to demonstrate its effectiveness as an accurate and consistent diagnostic tool.

Methods. Morphological classifications of LSS and quantitative measurements of key anatomical structures were combined using two CNNs. To classify central stenosis, models were trained on 1635 labeled lumbar spine MRI studies consisting of T2-weighted sagittal and axial planes at the level of each vertebra. The accuracy of the model was assessed using an external validation set of 150 MRI studies graded by a panel of 7 radiologists as: no stenosis, mild, moderate or severe spinal canal stenosis. The reference value for all types of stenosis was determined by majority vote, and in the event of disagreement, a decision was made by an external radiologist. The radiologists' interpretations were then compared with those of the trained model.

Results. The model demonstrated comparable performance to the average radiologist both in identifying the presence/absence of LSS and in classifying severity for all 3 types of stenosis. For central canal stenosis, the sensitivity and specificity of the CNN were (0.93; 0.85) for binary classification (presence/absence) compared to the average radiologist (0.86; 0.86). For lateral pocket stenosis, the sensitivity and specificity of CNN were (0.92; 0.80) compared to the radiologist's mean (0.83; 0.94). For foraminal stenosis, the sensitivity and specificity of CNN were (0.89; 0.86) compared to the radiologist's mean (0.81; 0.91). Multiclass classification of stenosis severity showed similar statistics.

Conclusions. CNNs showed comparable performance to radiologists in detecting and classifying LSS. The integration of neural network models in pathology detection could provide higher accuracy, efficiency, systematicity, and the possibility of subsequent interpretation in diagnostic practice.