Objective: to study the characteristics of orbital soft tissues in health. Material and methods. Computed tomography scans of 210 individuals (266 orbits) with no orbital abnormality were examined. Results. The paper presents the volumetric characteristics and parameters of the soft tissue density of the orbit and its apex (extraocular muscles, retrobulbar fat, optic nerve, lacrimal gland, eye, and vitreous body) in health. The internal surgical space fat at the orbital apex is estimated to be 75.35 and 73.83% of the total volume at the apex in men and women, respectively. The paper shows that individual asymmetry of orbital fat volumes in health is encountered in 47.61% of the men and in 51.42% of the women and ranges from 0.5 to 2.0 cm3. Conclusion. The volumes of orbital soft tissues in health are statistically significant different in the men and in the women. The asymmetry of the mean orbital soft tissue volumes in health is within the limits of statistical error.

Objective: to morphometrically estimate normal variations in the sizes of lacrimal sacs on the basis of computed tomography findings to optimize the choice of endoscopic surgical intervention tactics for dacryocystitis. Material and methods. Preoperative orbital computed tomography data were comparatively morphometrically processed in two groups of patients with or without clinically verified dacryocystitis. Results. Data on the typical variants of the sizes of the lacrimal sac in health and in clinically manifested dacryocystitis were obtained and statistically processed. The advantages of using the design volume of the lacrimal sac over other measurements were shown. A method for the morphometry of lacrimal sacs was proposed on the strength of computed tomography data. Conclusion. The obtained new refined data on the holotopy of the lacrimal sac in health and clinically verified dacryocystitis can simplify the choice of an approach to planning endonasal dacryocystorhinostomy.

Objective: to determine differences in cerebrospinal fluid (CSF) flow velocities in patients with varying degrees of communicating hydrocephalus (CH) versus a group of healthy volunteers without hydrodynamic disorders. Material and methods. The investigation enrolled 27 CH patients (17 and 10 patients with an Evans index of 0.31 and 0.46, respectively) and 62 healthy volunteers. Average, volumetric, and peak flow velocities were determined at different intracranial levels. Results. Analysis of differences between the mean values indicated that the patients with CH were observed to have progressive cranial cavity CSF outflow obstruction that depended on the degree of dilation of the ventricular system and, probably, on impaired CSF reabsorption. These changes can provide an explanation for the clinical symptoms present in the patients and also serve as diagnostic criteria. Conclusion. The investigation showed that phase-contrast magnetic resonance imaging might be used to estimate the quantitative indicators of CSF in health and in varying degrees of CH. The velocity characteristics of antegrade and retrograde CSF flows are significantly different in health and in disease, which may be relevant to neurologists and neurosurgeons when planning therapy and surgery options.

Introduction. The purpose of this prospective study was to compare radiological outcomes after total knee arthroplasty (TKA) with or without patellar resurfacing in patients with grade IV osteoarthritis on patellofemoral joint. Material and methods. 123 cases with Kellgren–Lawrence grade IV osteoarthritis on patellofemoral joint were enrolled for this study. At the operating room, they were randomly assigned to undergo patella resurfacing (62 cases) or patella retention (61 cases). Among them, 114 cases that could be followed for more than 2 years were included in this study (resurfacing group; 59 cases, retention group; 55 cases). Preoperative and postoperative radiological outcomes (mechanical femorotibial angle, patellar tilt and congruence angles) were evaluated and compared between two groups. Results. Preoperative radiological measures shows not significant difference between patellar tilt (P = 0.13), mechanical femorotibial angles (P = 0.62) and congruence angle (P = 0.37). Despite the difference performed methods of surgery, postoperative radiological assessment outcomes between two groups were almost identical Patellar tilt (P = 0,47), mechanical femorotibial angles (P = 0.34) and congruence angle (P >0.05). Conclusion. Obtained almost the same satisfactory radiological outcomes after patella resurfacing and retention groups after total knee replacement allows us to conclude that, primary TKA without patella resurfacing is a good treatment option in patients with high grade osteoarthritis of the patellofemoral joint.

Objective – to analyze radiation exposure due to computed tomography (CT) of brain, chest, abdomen and pelvis in a large multifield federal hospital and feasibility of low-dose CT-examinations. Material and methods. Retrospective analysis was performed using data from electronic patient records and PACS from a single multi-field hospital. Data were obtained from 1626 records of patients (794 men, 832 women; age range 17–93) scanned with 3 MDCT during one year. CT-examinations of good quality were selected, volumetric CT dose index (CTDI) and dose-length product (DLP) were collected for each of them. The effective doses (ED) were calculated using the normalized coefficients according to Russian Guidance. Results. Number and structure of CT-examinations for the years 2012–2014 in a multi-field hospital were analyzed. The mean effective dose (M±m) values with/without contrast medium (respectively), according to anatomical areas were as follows: brain – 2,34 ± 0,03/3,52 ± 0,23, chest – 4,83 ± 0,11/ 11,02 ± 0,82, abdomen-pelvis – 9,81±0,40/36,6±1,17, chest-abdomen-pelvis – 12,41 ± 0,79/35,63 ± 1,81 mSv. Conclusion. Results of this study give an example of CT dose values and distribution in a multi-field hospital. They are comparable with reference levels published of other authors. This experience should be expanded for creation of CT national reference values and for co-operation with international initiatives (EUROSAFE projects).

Objective: to determine the advantages of contrast-enhanced computed tomography (CT) over contrast-free studies in the differential diagnosis of hepatic, renal, and pancreatic space-occupying lesions. Material and methods. A team of experienced radiologists retrospectively used CT data of patients with different spaceoccupying lesions of the abdomen and retroperitoneal space (liver, kidney, and pancreas). Results. The diagnostic value of CT of the liver, kidney, and pancreas substantially decreases without using radiopaque contrast agents; at the same time not only the differential diagnosis, but also visualization of some neoplasms are frequently impossible. Conclusion. The potential benefit of contrast-enhanced CT virtually always outweighs the risks associated with the injection of a contrast agent.

Prostate cancer (PC) is one of the most important problems in modern oncology. According to statistical data, PC ranks second in the cancer morbidity structure in the Russian Federation and developed countries and its prevalence has been progressively increasing over the past decade. A need for early diagnosis and maximally accurate morphological verification of the diagnosis in difficult clinical cases (inconvenient tumor location for standard transrectal biopsy; gland scarring changes concurrent with prostatitis and hemorrhage; threshold values of prostate-specific antigen with unclear changes in its doubling per unit time; suspicion of biochemical recurrence or clinical tumor progression after special treatment) leads to revised diagnostic algorithms and clinically introduced new high-tech invasive diagnostic methods. This paper gives the first analysis of literature data on Russian practice using one of the new methods to verify prostate cancer (transrectal prostate cancer under magnetic resonance imaging (MRI) guidance). The have sought the 1995-2015 data in the MEDLINE and Pubmed. The account of the MRI-guided biopsy indications developed by K. Chan Kyo (2015) and adapted by the authors of this publication is of practical interest to specialists.