Objectives. To propose an multidetector computed tomography-based tool for quantitative differentiation between pancreatic neuroendocrine tumour (PNET) and solid pseudopapillary neoplasm (SPN) in clinical practice.

Methods. The retrospective study included 76 patients from January 2014 to March 2018. The final cohort of sixty-two patients was divided into two groups: PNET and SPN. Two radiologists independently analyzed MDCT data. We constructed two multivariable prognostic models for differential diagnosis between hypervascular PNETs and SPN, nonhypervascular PNETs and SPN via binary logistic regression. We used the receiver operating characteristic (ROC) curves to evaluate the prognostic value of any quantitative characteristics and to determine optimal cut- off values for differential diagnosis.

Results. Thirty patients with PNET comprised the first group. Thirty-two patients with SPN comprised the second group. For the first prognostic model selecting a cut-off value of 34% yielded the maximum sensitivity and specificity of 96.7% and 93.8%, respectively. Values larger than the cut-off value correlated with PNET. For the second prognostic model, selecting a cut-off value of 50% yielded the maximum sensitivity and specificity of 100% and 100%. Values larger than the cut-off value correlated with PNET.

Conclusion. We developed two diagnostic models for differential diagnosis between hypervascular, nonhypervascular PNETs and SPN. The models allow for increased confidence in the diagnosis. Finally, we created an on-line calculator for easy routine use http://pancreas-calculator.com).

Purpose: identification of the possibilities of computer tomography with contrast enhancement in evaluated of the degree of fibrosis and number of acinar structures in the pancreatic parenchyma at the preoperative period to predict the development of postoperative complications.

Material and methods: In the department of abdominal surgery in 2016-2019, 196 pancreatoduodenal resections were performed. Retrospectively selected group of patients (49). Patients were divided into 2 groups according with the postoperative period. The postoperative period was uncomplicated in 41 (84%) cases. Сlinically significant pancreatic fistula was in 8 (16%) cases. According to preoperative computed tomography with contrast enhancement, we evaluated: the structure of the pancreas; the density of the pancreas in the native phase of the scan (HU), parenchyma accumulation coefficient; parenchyma accumulation coefficient in the venous phase; parenchyma accumulation coefficient in the excretory phase; coefficient of relative washout of contrast enhancement of parenchyma. According histological we evaluated the number of fibrosis and acinar, fat cells in the section pancreas.

Results: "Soft" structure of the pancreas (r=0,747, p=0,000), parenchyma accumulation coefficient (r=0,631, p=0,000), the density of the pancreas in the native phase of the scan (r=0,568, p=0,000) positively correlated with complicated postoperative period and the number of acinar cells. Parenchyma accumulation coefficient in the excretory phase (r=0,562, p=0,000) positively correlated with the fibrosis pancreas and in the negatively correlated with the complicated postoperative period. The risk of developing pancreatic fistula is 3 times higher with values parenchyma accumulation coefficient greater than 1, sensitivity 75%, specificity 73%. The risk of developing pancreatic fistula is 3 times higher with values parenchyma accumulation coefficient in the excretory phase less than 0.45, sensitivity 75%, specificity 63%.

Conclusions: computed tomography with contrast enhancement allows the structure pancreas, the number of fibrosis and acinar cell sat the preoperative period to pick out the high-risk patient group to the development of postoperative complications.

The introduction of LDCT-based screening programs into clinical practice allows an additional assessment of the liver. It is known that medium-to-severe steatosis can be detected using LDCT. However, taking into account the increased image noise level and the fact that the liver is always only partly in the scan area, the question arises as to how accurately the liver density can be determined in LDCT relative to routine CT.

Purpose. Thus, the following objectives of this study have been established:
• To identify the differences between the mean density of the liver as measured by a CT and an LNDT.
• To compare the mean density between CT and LDCT in different patient subgroups depending on the mean liver density (<40 HU, 40–50 HU, 50–60 HU, and >60 HU).
• To determine the effect of image noise level on the mean liver density values on LDCT compared to CT.

Materials and methods. We analyzed 30000 patient records from 2017 to 2019.
Inclusion criteria: We included patients with both thoracic non-contrast CT and an LDCT and the time interval between the studies of less than 27 days.
Exclusion criteria: The absence of CT-LDCT pair, presence of focal liver lesions, known liver diseases, operated liver, anemia with blood density decrease below 40 HU, hands along the body instead of overhead.
Study protocol: LDCT was performed at 135 kV. The routine CT was at 120 kV. Scan length: from lung apex to pleural sinuses. The average radiation dose with LDCT was 0.6–0.8 mSv, and 2.8–4.6 mSv with routine CT. All scans were performed on two 64-detector units from the same manufacturer.
We measured liver density with the CTLiverExam software algorithm for automatic liver densitometry.
The statistical processing was done using the Stata14 program.

Results. We used data from 61 patients for statistical analysis. The average age was 53 years. The ratio of men to women was 23:38.
We did not observe statistically significant differences between CT and LDCT. With a breakdown by the initial liver density level, it turned out that in the subgroup 40-50 HU, the differences were statistically significant. No correlation between liver density and standard deviation for CT was revealed (p = 0.338). There was a mild anticorrelation for LDCT with a coefficient of -0.686 (p < 0.0001).

Conclusion. Our study shows that liver density measurement in thoracic LDCT is valid. In the context of lung cancer screening programs. An analysis of the image noise/liver density ratio on the LDCT shows an inversely proportional relationship: the higher the noise level, the more significant a “decrease” in liver density. This factor must be taken into account when interpreting the results CT and LDCT.

Aim. To evaluate the possibilities of dynamic lung CT using a low-dose scanning Protocol.

Materials and methods. The study is based on the experience of using two protocols of dynamic lung CT in 97 patients with single foci in the lungs. CT study was performed on a multispiral computed tomograph GE Optima CT660 with bolus administration of 100 ml of iodine-containing drug at a rate of 3.5 ml/sec. Native the study was conducted from the level of the jugular notch to the diaphragmatic sinuses. After that, the focus area was scanned for 30 seconds, 1, 2, 4, 6, 15 minutes after administration of contrast agent. Depending on the scanning Protocol used, the patients were divided into 2 groups. The Protocol of the first group of patients (n = 20) included the following parameters: radiation field (Nativ/contrast phase) – 270–340 mm/100-140 mm; voltage – 120 kV; the current 80–400 mA; rotation time of the tube – 0,6 sec; slice thickness 5 mm. the parameters of the scanning Protocol of the second group of patients (n = 50): radiation field (Nativ/contrast phase) – 270–340 mm/30–45 mm; voltage – 100 kV; the current 80–400 mA; rotation time of the tube – 0,6 sec; the slice thickness is 5 mm. Quantitative assessment included measurement of effective dose. Qualitative assessment of each study included the analysis of the CT scans obtained with an assessment of the degree of “noise” of the image and its impact on the interpretation of the obtained CT data.

Results. In the first group of patients, the tube voltage was 120 kV, the irradiation field in the native phase was within 270–340 mm, in contrast phases of the study-within 100–140 mm (124.5 ± 12.8 mm), while the effective dose ranged from 13.7 mSv to 21.5 mSv and averaged 18.1 ± 2.4 mSv. In the second group of patients radiation field in the native phase was in the range of 270–340 mm, the contrast phase of the study – in the range of 30–45 mm (36.0 ± 6.1 mm), the effective radiation dose was varied in the range of 5.1 mSv – 10.2 mSv and the average was 7.6 ± 1.7 mSv.

Conclusion. The use of the developed Protocol of CT-study in the dynamic CT of the chest provides a reduction in the dose of radiation by an average of 42% while maintaining an adequate assessment of the data on the accumulation and leaching of contrast agent formation.

Objective: to determine CT features of pneumonia depending on the etiological agent in patients with LHP
after chemotherapy.

Materials and methods. 52 patients with LPD, who developed pneumonia, underwent chest CT. In all patients, the causative agent of lower respiratory tract infection was verified by microbiological diagnostic methods.

Results. In the first 48 hours from the onset of the viral pneumonia, thickening of the interlobular septa and of peribronchial interstitium, part-solid and solid nodules, and hydropericardium (p < 0.01) were detected. After 48 hours, ground glass opacity, Intralobular septal thickening, “crazy-paving” pattern and hydropericardium were more often detected (p < 0.001). In the first 48 hours from the onset of invasive pulmonary mycosis, a halo sign (p < 0.01) and the prevalence of changes in the upper parts of the lungs (p < 0.05) were detected. After 48 hours, halo sign (p <0.01), a random distribution of nodules and solid nodules (p < 0.05) were detected.

Conclusion. Viral or fungal etiology of lower respiratory tract infection can be excluded according to CT data with sufficient certainty, and that is undoubtedly a fundamental reason for changing further treatment tactics in such patients.

According to the literature, fMRI analysis at resting state (RS) is an informative methodological approach to the study of the basic level of a healthy and diseased brain’s functional activity. Averaging data over observation groups for various forms of cerebral pathology is often unacceptable. Previously, we mastered and applied the Independent Component Algorithm (ICA) in FSL software to visualize and analyze individual fMRI resting networks of healthy people.

Objective: to analyze individual fMRI resting networks associated with the state of motor activity and consciousness in patients with severe traumatic brain injury (STBI).

Materials and methods. Observation groups: 23 patients with SТBI (main) and 17 healthy volunteers (control). 3T fMRI recorded at rest. Individual (norm and STBI) and group (norm) analysis of RS networks was carried out by FSL software (ICA algorithm) and SPM8 in MATLAB.
For the DMN and Sensorimotor networks, topography and total volume and intensity of their activation of their activation were determined.

Results. The topography features reproduced in the group and individual analysis of fMRI of healthy people, as well as the averaged quantitative indicators of the rest networks were used as reference for pathology.
In the context of motor activity, the RS Sensorimotor network was considered. Its topography is close to normal in most patients without or with mild hemiparesis. The growth of this defect is accompanied by a decrease in the integral quantitative indicators of the network, combined with asymmetric reduction (lack of activation in the contralateral motor cortex) in rough hemiparesis.
In the context of consciousness, the expression and characteristics of the DMN network were compared in healthy people and in patients with STBI at its various levels: from clear to chronic vegetative state. It was revealed that a decrease in the level of consciousness is accompanied by a reduction in the cortical components of DMN, primarily the frontal (anterior DMN), not pronounced in the vegetative state. Activation of the caudal component of DMN (in particular, the posterior cingular cortex) persists in patients with depressed consciousness: distinct and even somewhat enhanced compared to the norm with its reversible form, less pronounced with chronic

Conclusion. The data obtained indicate the informative value of fMRI analysis of individual resting networks in the context of studying cerebral structural and functional foundations of consciousness and motor activity, as well as diagnosing the state of these functions in STBI.

Cerebral aneurysms are the cause of hemorrhage in the subarachnoid space of the brain and are associated with high early mortality and risk of complications. Timely diagnosis and successful treatment of arterial aneurysms (AA) of the brain before rupture will help to avoid the consequences of subarachnoid hemorrhage (SAC).

The purpose of the study was the estimation of transcranial duplex sonography (TDS) sensitivity in AA visualization and determination of AA ultrasound criteria.

Materials and methods. 41 patient with cerebral aneurism rupture were participated in the research. All patients were examined by TDS on a device on the Aplio ™ 500 device (Toshiba) using a 2.5 MHz sensor and by selective cerebral angiography (CAG) on the Siemens diagnostic unit (Axion Artis DBS). Non-ionic contrast agents omnipak 300 and Ultravist 320 were used for CAG.

Results. TDS application it allowed to visualize 60.4% of aneurysms, as well as determine the diameter of the aneurysm and the nature of blood flow in it. According to our data, when using color or energy Doppler mapping modes of the vehicle, the frequency of visualization of the M1 SMA segment was 100%, the M2 segment -40.5%, the PMA – 100%, and the P1 and P2 segments of the ZMA – 90%. A strong correlation was found between angiographic and ultrasound (TDS) dimensions of AA (r= + 0.89; p < 0.0001).

Conclusions. TDS is not the gold standard in the diagnosis of AA, but can be used for routine examination of patients with cerebral aneurysms. Main ultrasound criteria for imaging AA: education is rounded or oval in shape, associated with the vessel; a color area division between vessel and education; the presence of revealed the formation of turbulent blood flow and unidirectional blood flow through the peripheral vessels related to education.

Introduction. MDCT is more sensitive in pulmonary, pleural and bone injuries detection in patients with polytrauma than chest radiography. High-quality multiplanar reconstructions brought additional information to the diagnostic capabilities of this method.

Purpose. Purpose of this publication was to analyze the data obtained during chest MDCT in children with polytrauma.

Material and methods. 147 children aged from 6 months to 17 years with polytrauma and chest injuries were studied. MDCT was performed on Philips Brilliance CT 16 and 64.

Results. We retrospectively evaluated CT and clinical data of 147 patients, the main reason of polytrauma were traffic accidents (n = 91 – 61.9%), the rest was caused by fall from a height (56 – 38.1%). In 80% of cases the injury was severe and complex with not only lungs and chest damage, but also with other parts of the body: the head, the stomach, the pelvis and the limbs. Among 147 patients, pulmonary parenchyma damages in the form of injuries, less gaps, were detected in 70% of cases, pneumothorax – in 30% of cases, hemothorax – in 15%.

Conclusion. MDCT significantly improves the detection of pulmonary damage in blunt thoracic trauma due to better visualization of bone, soft tissues and blood vessels damage and the possibility of obtaining multiplanar image reconstructions. MDCT allows to identify lung contusions and to differentiate areas of atelectasis and tears, to evaluate and calculate their volumes, and therefore should always be used as a primary imaging method in patients with polytrauma.

Aaneurysmal bone cyst is a benign tumor-like bone lesion with an uncertain etiology with many blood-filled cavities.
As an independent nosological form, this disease was isolated in 1942.
There are several theories of the etiology of the primary aneurysmal bone cyst, including a response to traumatic local hemorrhage, reactive damage due to changes in the intraosseous blood flow, and true neoplasm secondary to gene rearrangements. The primary form of aneurysmal bone cysts must be differentiated from the secondary form – the latter develops against the background of bone pathology. About one third of all cysts develop against the background of a giant cell tumor, osteoblastoma, or chondroblastoma. 
Aneurysmal bone cysts are mainly observed in children and adolescents, with 80% occurring in patients under the age of 20–30. Women suffer a little more often M: F = 1: 1.16.
Aneurysmal bone cysts can lead to a pathological fracture, which can dramatically worsen symptoms. Inside the spine, lesions can cause neurological disorders caused by massive exposure to the spinal cord or exit from nerve roots. Since they usually manifest in the pediatric population, growth plates can be affected, resulting in deformation of the limb.
In practice, diagnosing AKC can be difficult. The differential diagnosis includes a giant cell tumor, fibrous dysplasia, a simple bone cyst, ossifying hematoma, chondroma, chondromyxoid fibroma, enchondroma, hemophilic pseudotumor and metastases. ACC is not a neoplastic lesion and it is very important to differentiate this nosology from malignant bone lesions.
This article presents a rare clinical case of aneurysmal bone cyst of the frontal sinus and cells of the ethmoid labyrinth in a child before and after treatment.
Purpose. Demonstration a clinical case of aneurysmal bone cyst before and after surgical treatment.

The experience of using ultrasound diagnostics for endovascular treatment of May-Turner syndrome is given.

The purpose of the study was to evaluate the diagnostic capabilities of ultrasound examination of stents of the iliac veins in patients with varicose pelvic disease in the presence of May–Turner syndrome.

Material and methods. 13 patients with May–Turner syndrome and associated pelvic varicose veins were studied. The following methods were used for instrumental diagnostics: ultrasound examination of the pelvic veins, multispiral computerized phlebography, radiopaque phlebography.

Results. 10 women had pelvic enlargement. Dilation of the veins of the plexus plexus from 5 to 11 mm, uterine veins from 4 to 8 mm, and ovarian veins from 5 to 7 mm was noted. After stenting, the pelvic veins were reduced. In 9 patients, stents functioned throughout the observation period. In 1 patient, stent thrombosis was diagnosed the next day, in 1 – after 10 days. After selective catheter-driven thrombolysis and restenting, stents are passable. In 2 patients, partial stent thrombosis was diagnosed after 1 month, patients continue to be observed with parietal thrombomasses in stents.

Discussion. The diagnosis of May–Turner syndrome and varicose veins of the pelvis was made in the hospital at the diagnostic stages of the study. Already 3 months after stenting, we observed a decrease in the diameter of all the pelvic veins. Endovascular stenting is the modern and most effective method for restoring iliac vein patency for patients with SMT. During ultrasound, we completely located the stents in various planes and gave a full description of their functioning, occlusion and parietal thrombosis.

Conclusion. ultrasound is a non-invasive and highly effective method for the diagnosis of varicose pelvic disease in patients before and after endovascular treatment of May-Turner syndrome.

This article provides an overview of the main literature data of biochemical basics and the clinical application of positron emission tomography, one of the promising technologies of radiation imaging in oncology.
In the current part we discuss in detail the biokinetics of radiopharmaceuticals used to visualize various groups of tumor cells receptors. These include angiogenesis markers - RGD peptides, ligands for somatostatin receptors, agents for sex hormone imaging, ligands for prostate-specific membrane antigen and to activating EGFR mutant kinase. It contains results of studies that were dedicated to search for optimal modifications of these radiopharmaceuticals to increase diagnostic efficiency, their comparative analysis is carried out, the results of their use in cancer research and development prospects in this industry are highlighted.