Objective – to study the characteristics of the distribution and visualization of ganglionated plexuses in the left atrium (LAGP) in healthy volunteers.

Objective and methods. The investigation enrolled 15 healthy volunteers (median age 31 [26; 41] years). The investigation participants successively underwent cardiac computed tomography (CT) and SPECT using the neurotropic radiopharmaceutical 123I-MIBG. The obtained images were combined to identify and assess sympathetic activity foci (SAF) in the left atrium. The identified SAFs were ranked with a confidence probability (CP) on the basis of their correspondence to the anatomical location of LAGP, as well as the discreteness and prevalence of the surrounding structures.

Results. A total of 36 SAFs (median per participant was 2 [2; 3]) were identified; of them 20 (56%) had a low CP (median per participant was 1 [1; 2]); 16 (44%) had intermediate and/or high CP (median per participant was 1 [1; 1]). Three investigation participants (3/15) were found to have no SAFs with an intermediate and/or high CP. SAFs with an intermediate and/or high CP most frequently corresponded to the location of the left and right upper LAGPs (4/16 and 3/16 cases, respectively).

Conclusion. Hybrid SPECT/CT with the neurotropic 123I-MIBG allows the identification of SAFs in healthy volunteers, which correspond to the typical location of LAGPs. 

Objective – to compare the diagnostic efficiency of whole-body diffusion-weighted magnetic resonance imaging (DW-MRI) and positron emission tomography combined with computed tomography (PET/CT) in the staging of lymphomas.

Material and methods. The prospective study enrolled 92 adult patients with Hodgkin's lymphoma or non-Hodgkin's lymphoma. Before treatment, all the patients underwent whole-body DW-MRI and PET/CT. The techniques were compared for their efficiency in diagnosing damage to lymph nodes (LNs) and organs and in determining the stage of lymphoma.

Results. The sensitivity, specificity, and accuracy of DW-MRI in diagnosing a lesion in the enlarged LNs were 98.2%, 99.9%, and 99.3%, respectively; those of PET/CT were 99.4%, 100.0%, and 99.8%. ROC analysis showed that the efficiency of the techniques in diagnosing a lesion in the enlarged LNs did not differ (p>0.06). The sensitivity of DW-MRI and PET/CT in diagnosing a lesion in the unenlarged LNs was 77.8% and 88.1%, respectively (p<0.001). The sensitivity, specificity, and accuracy of DW-MRI in diagnosing lung damage were 73.3%, 98.7%, 94.6%; those of PET/CT were 86.7%, 98.7%, and 96.7%; those for the spleen were 54.8%, 98.3%, 83.3% and 100.0%, 100.0%, 100.0%; those for bone marrow (BM) were 87.1%, 96.4%, 93.0% and 64.5%, 87.3%, 79.1%,; those for all organs were 72.9%, 98.1%, 91.4% and 80.0%, 96.6%, 92.2%. The ROC analysis indicated that the efficiency of the techniques in diagnosing a lesion in the lung did not differ (p>0.3), that of PET/CT for the spleen was higher (p <0.0001); that of DW-MRI for BM was higher (p<0.0008); that for all organs did not differ (p>0.35). DW-MRI and PET/CT could determine the correct stage of lymphoma in the same number of patients (86%). The new lymphoma staging algorithm involving whole-body DW-MRI in all patients, PET/CT, and BM biopsies according to the established indications made it possible to determine the correct stage of lymphoma in 95% of patients.

Conclusion. Whole-body DW-MRI has comparable efficiency to PET/CT in the staging of lymphoma. The new lymphoma staging algorithm based on whole-body DW-MRI is superior to PET/CT and PET/CT with BM biopsy.

Objective: to study the capabilities of single-source dual-energy computed tomography (DECT) in quantifying the concentration of iodine in solutions.

Material and methods. Single-source DECT was performed using a phantom containing a set of 5 tubes with a different titer of the iodine-containing contrast agent Iopamidol. Further, the obtained images were used to construct iodine maps; and the concentration of iodine was measured within the volume of the titrated contrast agent.

Results. Despite a high correlation between the measured iodine concentration in solution with the true concentration (Pearson's correlation coefficient r = 0.98; p < 0.01), there is a measurement error that was 4.8 to 23% at different dilutions.

Conclusion. Signal-source rapid voltage switching DECT does not allow precise measurements of the true concentration of iodine in solution. To eliminate measurement errors in further in vivo studies using singlesource DECT, it may be that attention must be paid to the measurement of normalized iodine concentration. 

Objective: to estimate the diagnostic value of the anatomical characteristics of the intracisternal portions of the trigeminal nerves and adjacent arteries in diagnosing classical trigeminal neuralgia (TN).

Material and methods. Fast Imaging Employing Steady-state Acquisition (FIESTA) using an isotropic MRI sequence was used to analyze the anatomical characteristics of the intracisternal portions of the trigeminal nerves and adjacent arteries in 133 patients, including 86 patients aged 55±11 years with clinically and surgically verified TN and in 47 patients aged 51±16 years in the control group. The investigators measured the cross-sectional areas of the trigeminal nerves at 5 mm from the pons cerebelli, the ratio of the largest-to-smallest nerve diameters at similar points, the distance to the adjacent arteries, and that between the closest neurovascular contact (NVC) point and the pons cerebelli. Characteristic curves (CC) were constructed and reference points with the highest specificity were selected with an acceptable sensitivity level for all parameters. Positive and negative predictive values (PPV and NPV, respectively) are determined for each reference point.

Results. The area under the CC was equal to 0.77 for the ratio to the diameters of the trigeminal nerves near the pons cerebelli. At a reference point of 1.89, the sensitivity/specificity (Se/Sp) ratio was 0.57/0.82 with a PPV of 0.74 and an NPV of 0.83. The area under the curve for the cross-sectional areas of the trigeminal nerves at the pons cerebelli was 0.76. The reference point with an area of 3.65 mm2 yielded a Se/Sp ratio of 0.52/0.8 with a PPV of 0.51 and an NPV of 0.91. The distance to the adjacent artery gave an area under the CC of 0.72. The Se/Sp ratio at a reference point of 1.65 mm turned out to be 0.53/0.789 at a PPV of 0.55 and an NPV of 0.92. The area under the CC for the distances between the NVC point and the pons cerebelli was 0.75. The reference point of 4.05 mm with a Se/Sp index of 0.6/0.78 was characterized by a PPV of 0.77 and an NPV of 0.94.

Conclusion. All the analyzed anatomical parameters showed an acceptable diagnostic value in diagnosing TN. Certain reference values of the parameters can be used to diagnose TN with the highest acceptable specificity at the maximum NPV to reduce frequent false-positive results. 

Objective: to increase the accuracy of computed tomography (CT) in the diagnosis of hepatomegaly.

Material and methods. The investigation is based on the analysis of the results of 603 abdominal CT examinations, which are available in the radiology information systems of the city of Moscow. Six liver parameters (the transverse, vertical, and anteroposterior dimensions of the right and left lobes) were measured. The volume of the organ, the right and left lobes was determined when building three-dimensional images with an IntelliSpace Portal multimodality station (Philips) and a special Synapse 3D software system (Fuji).

Results. It was established that there was the most pronounced relationship to the true liver volume among all sizes when using only one parameter for the anteroposterior size of the right lobe (r = 0.66), the sum of the two ones for the vertical and anteroposterior sizes of the right lobe (r = 0.83), the sum of three sizes for the vertical, anteroposterior, and transverse dimensions of the right lobe (r = 0.86). ROC analysis was used to calculate the threshold values of the sum of two and three proposed parameters (34 and 42 cm, respectively). The sensitivity of the technique in identifying hepatomegaly, which was established on the basis of the sum of the vertical and anteroposterior dimensions of the right lobe, compared with only one-parameter orientation, increased from 26% to 87%; the specificity rose from 53% to 86%; when using the sum of the vertical, anteroposterior, and transverse dimensions of the right lobe, that was as much as 89% and 84%, respectively. Approximating the cubic root of the volume with the least squares method allowed one to create new and convenient formulas for calculating the volume of the liver.

Conclusion. Determination of the sum of the vertical and anteroposterior dimensions of the right lobe (threshold value, 34 cm) is an optimal approach to diagnosing hepatomegaly. If there is a need for knowledge of the volume of the liver in the absence of special programs for its segmentation, data can be obtained using the created formula that takes into account two proposed liver sizes. 

Objective: to determine treatment policy for an acute surgical disease in patients with late-stage HIV infection diagnosed using the data of the highly informative imaging techniques multislice computed tomography (MSCT) and magnetic resonance imaging (MRI).

Material and methods. In 2008 and 2016, the authors examined 425 patients (320 men and 105 women) with acquired immunodeficiency syndrome (AIDS) who were treated at the surgical units of the Surgut Regional Clinical Hospital, by using the data of MSCT (Toshiba Aquilion 64, Japan) and MRI (Siemens 1,5T Magnetom Essenza, Germany) in identifying both local surgical and general mixed diseases.

Results. Analysis of acute surgical diseases of the abdominal cavity and retroperitoneal space in patients with late-stage HIV infection determined that the treatment policy in this category of patients depended on clinical diagnostic data.

Conclusions. 1. MSCT and MRI are highly informative techniques in diagnosing acute surgical diseases in patients with late-stage HIV infection. 2. The course of an acute surgical disease in patients with late-stage HIV infection in the presence of generalized opportunistic infection makes it preferable to perform minimally invasive surgical interventions. 

Objective – to assess the informativeness of multisclice computed tomography (MSCT) angiopulmonography in the assessment of peripheral blood flow and to determine the prognostic role of angiographic massiveness and volume of preserved peripheral blood flow as predictors of success of emergency surgical treatment of acute massive pulmonary embolism (PE).

Material and methods. The article presents the results of 7-year work for the period from March 2012 to September 2019, which included a pilot retrospective stage (analysis of the results of 264 MSCT procedures with contrast enhancement for acute PE in patients aged 32 to 69 years for the period 2012–2013) and prognostic practical work (the second stage, analysis of the results of 974 MSCT procedures with contrast enhancement in patients aged 25 to 78 years for the period 2013–2019).

Results. The obtained results and statistical dependences proved the influence of the saved volume of peripheral arterial pulmonary blood flow on the outcome of surgical treatment. The use of this indicator as an MSCT predictor reduced the hospital mortality rate from 7.2% to 3.5%. The analysis of the influence of the initial angiographic massiveness of PE on the outcome of surgical treatment has not been confirmed.

Conclusion. According to the results of the study, we recommend the inclusion of segmental arterial pulmonary blood flow analysis by MSCT with contrast enhancement in the algorithm of preoperative examination of patients with acute massive pulmonary embolism in case of emergency surgical treatment. 

This scientific review assesses the current diagnostic capabilities of diffusion-weighted images used in the magnetic resonance imaging protocol for bladder cancer. It actualizes this impulse sequence employed within the framework of a multiparametric MRI study as one of the functional techniques. The review deals with the possibilities of diffusion-weighted images used in an independent version and in combination with T2-weighted images to visualize a tumor, postoperative changes, and associated pathology. It gives differential diagnostic criteria in identifying the extent of tumor invasion, including that with accuracy assessment according to the measured diffusion coefficient.

The sources of the review are publications included in the peer-reviewed databases PubMed, Scopus, eLIBRARY and the open sources Google Scholar, Researchgate. 

Objective of this article – to evaluate possibilities to visualize cardiac visceral adipose tissue by echocardiography, computed tomography (CT), and magnetic resonanse imaging (MRI) and to systematize data on its physiological and pathological roles. To achieve this goal, the authors analyzed relevant Russian and foreign sources of literature in the scientific libraries eLIBRARY and PubMed, by using the keywords: “pericardial fat”, “epicardial fat”, “visceral fat of the heart”, “epicardial adipose tissue”, “pericardial adipose tissue”, and “adipocytokine”. Actual data as of November 2018 were collected. The review presents up-to-date data on the physiological and pathophysiological roles of cytokines secreted by pericardial adipose tissue, as well as on correlations and possible theories of the relationship between the volumes of pericardial adipose tissue and the development of coronary heart disease, atrial fibrillation, and metabolic syndrome. According to echocardiography, epicardial adipose tissue thickness is a reliable predictor for the presence of high-risk atherosclerotic plaques in the coronary arteries. Adipose tissue volume can be measured with high accuracy using CT (manual, semi-automatic, and automatic methods).

A number of studies prove that MRI can be used for assigned tasks. The current notion of the role of these adipose depots can potentially be used in assessing the risk of cardiovascular diseases. The literature review presented confirms that visceral adipose tissue of the heart has a direct effect on the myocardium and coronary arteries and can be quantified using echocardiography, CT and MRI.