The aim was to study the dynamics of renal function in relation to the fibrosis activity and the arterial stiffness in young and middle-aged patients with atrial fibrillation (AF). Materials and methods. 50 young and middle-aged men with AF were examined. The average age was 53.0 (48.0-58.0). The serum levels of creatinine and cystatin C (Cys C) were determined and the glomerular filtration rate (eGFR) was calculated initially and after 12 months. The activity of systemic fibrosis was assessed by serum metalloproteinase-2 (MMP-2) and transforming growth factor-ß1 (TGF-ß1) determining. To assess systemic vascular stiffness central aortic pressure and pulse wave velocity (PWV) were measured. Results. Renal impairment defined as eGFR decrease by more than 10 ml/min/1.73 m² or to the level below than 60 ml/min/1.73 m² throughout the year was registered in 10 (20.0 %) patients. The concentration of MMP-2 and TGF-ß1 was higher in the subgroup with the eGFR decline compared to the patients without renal function impairment (21.1 (17.4-25.9) and 16.5 (13.0-19.2) ng/ml (p = 0.038); 3.01 (0.09-17.4), and 0.08 (0-1.3) ng/ml (p = 0.041). Central aortic pulse pressure was also higher in the patients with eGFR decline (45.5 (42.0-49.0) and 38.0 (31.0-41.0) mmHg; p = 0.036). The PWV levels did not differ in the subgroups. Conclusion. The renal function impairment throughout a follow-up period of 12 months was registered in 20.0 % of young and middle-aged patients with AF. This subgroup of AF patients was characterized by increased activity of systemic fibrosis and vascular stiffness in terms of matrix metalloproteinase-2, transforming growth factor-ß1 and central aortic pulse pressure levels.

The complications of arterial hypertension cause more than a half of 17 million cases of cardiovascular mortality in the world. According to the official statistics in 2010 Mongolia was the leader among the countries of the Asian Pacific region in mortalityfrom complications connected with arterial hypertension (40.9 people per 100 000 of population). It is proved that lifestyle change with risk factors correction and adequate hypotensive therapy allow to control arterial hypertension in most patients. The real prevalence of the resistant arterial hypertension in the world is less than 10 %. However, in clinical practice even in countries with high income only 50-60 % of persons with arterial hypertension can reach the target blood pressure values less than 140/90 mmHg, in Mongolia, these indicators are worse. Such situation leads to growth of mortality and disability, therefore it is a serious worldwide problem for health care. There are four reasons, which lead to low compliance of patients to be treated: social and administrative problems; medical passivity; irrational therapy and low adherence of patients to recommendations of doctors. But according to different cohort studies, the main reason of poor control of arterial hypertension in Mongolia is insufficient hypotensive therapy, therefore only 23.6 % patients can achieve the target blood pressure values. In such conditions, it is too important to develop a strategy aimed at improving control of arterial hypertension in Mongolia.

The aim of the research: to assess neurovegetative status according to the variability of the heart rhythm in pregnant women with idiopathic ventricular extrasystole and to estimate the efficiency of beta-adrenoblockers in this category of patients. Materials and methods. To study the variability of the heart rhythm daily ECG recording was made in 38 pregnant women with ventricular arrhythmias. Control groups consisted of somatically healthy pregnant and non-pregnant women. Patients with sympathicotonia detected during Holter ECG monitoring were given metoprolol in a dose of 25 mg per day. The efficiency of the treatment was assessed by Holter ECG monitoring one week after the start of therapy. Results. It was found that the decrease of the main time and spectral indices of cardiac rhythm variability is characteristic for pregnant women with idiopathic ventricular arrhythmias V gradation by Ryan. In addition in this category of patients against the background of a lower total cardiac rhythm variability there was a significantly greater contribution of central neurohumoral influences (VLF%) and on the contrary - a smaller contribution of peripheral vagal influences (HF%). In control Holter ECG monitoring after a week use of metoprolol ventricular tachycardia was not recorded. Conclusion. In pregnant women with ventricular extrasystole V gradation by Ryan overexertion of adaptive processes in the form of a predominant influence on the regulation of the rhythm of the heart of higher vegetative centers and moderate sympathicotonia were detected. A small doses beta-adrenoblockers therapy showed high efficiency in the treatment of ventricular tachyarrhythmias in patients with autonomic dysfunction.

Despite preventive measures, the problem of HIV infection in the Russian Federation remains important. The goal of prevention programs is to prevent the spread of HIV infection among the population. There are three levels of prevention. Primary prevention is aimed at the general population and is to minimize exposure to risk factors. It includes testing of donated blood for HIV, prevention of drug and alcohol abuse, education and training to promote safe sex, safe injection practices, circumcision, and the use of microbicides. Secondary prevention aims at early diagnosis for the disease and counselling of infected persons to prevent infecting others. Tertiary prevention aims to prevent disease progression and development of complications, and includes treatment, rehabilitation and social support for people living with HIV. Measures of tertiary prevention are partly fulfilling the role of primary preventive measures. Therefore, a high level of patients' adherence to antiretroviral therapy can significantly reduce the risk of transmitting the virus to their sexual partners due to the suppression of viral replication and therefore help reduce the spread of the disease among the population. In different subpopulations and regions, the importance of factors influencing epidemic process differs. Prevention programs should take into account the characteristics of the epidemic in each region. The review analyzes various directions, strategies and programs of HIV prevention, which are effective among the population.

The incidence and mortality rate of C. difficile infection (CDI) has increased remarkably over the last 10-20 years. CDI is a leading cause of healthcare-associated infections and antibiotic-associated diarrhoea. Increasing incidence and severity of CDI may be related with frequent antibiotic use and the emergence of a hypervirulent C. difficile strain. The epidemic strain NAP1 / BI / ribotype 027 is more resistant to antibiotics and produces more toxins and causes outbreaks around the world with increasing mortality and severity. Recent reports have documented that C. difficile infections occur among patients without traditional risk factors and the incidence of community-acquired CDI has increased. The clinical presentation of CDI ranging from the asymptomatic carrier to pseudomembranous colitis and toxic megacolon. The rate of recurrent CDI is 20-30 %. Early surgical consultation should be considered in all patients with severe or fulminant CDI. The preferred method for diagnosis CDI is stool testing using enzyme immunoassay (EIA) screening to look for glutamate dehydrogenase (GDH) antigen and toxins A and B. Metronidazole and vancomycin are recommended antibiotics for the treatment of CDI. Novel approaches include fidaxomicin therapy, monoclonal antibodies, and fecal microbiota transplantation. Fecal microbiota transplantation has shown relevant efficacy to overcome C. difficile infection and reduce it.

Background. Early detection of tick-borne pathogens in blood samples of infected people prevents the disease before clinical manifestations using antibiotic and immunoglobulin treatment. As far as tick-borne diseases are associated with significant activation of innate immune response, the changes in the cytokine profile soon after a tick bite could be used as an indicator of early tick-borne infection. Aims. The goal of this study was to characterize the production of cytokines during first 2-4 days after a tick bite in asymptomatic people infected with tick-borne pathogens. Materials and methods. The infection of tick-borne encephalitis virus, B. burgdorferi sensu lato, A. phagocytophilum and E. chaffeensis / E. muris was detected in blood of bitten humans using appropriate commercial real time RT-PCR and ELISA assays. Concentration of 14 cytokines in plasma of 89 infected and 45 non-infected people was established using quantitative ELISA kits. Results. Between 2^nd and 4^th days after tick bite, the prevalence and concentration of certain cytokines in blood of infected people significantly differed from those of the control group. Bacterial pathogens exhibited very similar patterns of cytokine profiles with induction of IL-1a, IL-8 и IFN-a and suppression of SOD, IL-1Ra и IL-17A. For virus infection the increased concentrations of IL-1 a, IL-8, IL-10, IL-17A, IFN-y and SOD were detected. The only suppressed cytokine was IL-1Ra receptor antagonist. Conclusions. The results suggest that evaluation of innate immune response between 2^nd and 4^th days after the tick bite could be a useful tool for evaluation of the risk of tick-borne disease for the humans bitten by ticks.

Possibilities of using eukaryotic microorganisms (Candida spp.) of microbiocenoses of mucosal open cavities as potential biomarkers of pathological states of biotopes were investigated. To identify biotopes characterizing Candida strains we used new promising natural glycoconjugate recognition agents -lectins that imitate the effect of probiotics. The lectins were isolated from cultures of probiotic strains of lactobacillus and bifidus bacteria characterizing and supporting probiotic compartment of microbiocenosis of human mucosal open cavities as part of endogen sensory system "lectins of probiotic microorganisms - opportunistic eukaryotic yeast-like fungi". The study was carried out on examples of cases of dysbiotic disorders in the composition of microbiocenoses against the background of pathologies of the urogenital tract of patients with established diagnosis. Results demonstrate the early (before development of visible inflammatory reactions) presence of changed Candida cells in pathological biotopes of urogenital tract indicating states of diseases characterizing with increased differentiating affinities and sensitivities of Candida to a panel of probiotic lectins. Probiotic lectins are perspective in combinative prognostics and diagnostics of pathological states of functional biotopes of human mucosal open cavities as well as for prophylaxis and therapy of such states by compensation of deficit or absence of probiotic microflora to support healthy balance of mucosal immunity, instead of probiotics or in combinations with probiotics, antibiotics and other antimicrobial agents, therapeutics, and factors. The data also perspective in study of pathological biotope states possessing risk of conversion into tumor-like landscapes.

The current article describes the determined blood supply areas of each of the suprarenal arteries. It is stated, that the intraorganic arteries branch out in the capsule and cortex mainly dichotomically, while in the brain matter the arteries are distributed according to the evriareal type of the vascular tree. The superior suprarenal arteries supply blood to the upper pole of the adrenal gland, to its anterior and posterior surfaces till the level of the horizontal fissure. The area of the blood supply ranges from 1.95 х 10³ to 4.12 х 10³ mm², the degree of involvement 34 %. The middle suprarenal artery branches gives off branches in the area of the medial pole and middle third of the adrenal gland and also in the area of the medial part of the renal surface. The size of the blood supply area - from 1.4 х 10³ to 2.83 х 10³ mm². The rate of involvement into the blood supply - 22.96 %. The branches of the inferior suprarenal artery supply blood to the inferior surface of the adrenal gland, and some of these branches reach its lateral pole. The size of the blood supply area here is from 1.75 х 10³ to 3.24 х 10³ mm², the rate of involvement into the blood supply is on the second position -26.53 %. The smallest area of blood supply of the adrenal gland is covered by the collateral suprarenal artery, which in 47 % of cases branches from the arcuate artery of the adipose capsule of the kidney (from 1,26 х 10³ to 1,93 х 10³ mm²). The rate of involvement -16.47 %.

Parkinson's disease is a long-term degenerative disorder of the central nervous system. Parkinson's disease typically occurs in people over the age of 60, of which about one percent are affected. Clinical features of Parkinson's disease consist of motor and non-motor disorders. Motor disorders include such symptoms as tremor, hypokinesia, rigidity, postural instability. Non-motor disorders include cognitive and emotional impairments, vegetative disturbance. There is no cure for Parkinson's disease, treatment is directed at improving symptoms. There are medication and non-medicated methods of treatment in Parkinson's disease. In earlier stages of Parkinson's disease dopamine agonists and monoamine oxidase type B can be very efficacious in relieving motor symptoms. The most effective therapy for Parkinson's disease is levodopa, which is converted to dopamine in the brain. Levodopa can lead to unpleasant side effects, such as shortened response to each dose, painful cramps, and involuntary movements; its use is often delayed until motor impairment is more severe. For some individuals with advanced, unmanageable motor symptoms, surgery may be an option - deep brain stimulation (DBS), when the surgeon implants electrodes to stimulate areas of the brain involved in movement. In another type of surgery, specific areas in the brain that cause Parkinson's symptoms are destroyed. External brain stimulation is one of the modern and high-technology method. This study presents results of mobile personified complex therapy with external brain stimulation in patients with parkinsonism.

Introduction. Convexital localization of cerebral arteriovenous malformations (AVM) is a good prognostic criterion for successful endovascular treatment. Difficulties begin in the final stages of large AVMs, in the transit nature of afferents. Transvenous embolization has been developed as an alternative to microsurgery and radiosurgery for a limited range of malformations. Materials, methods, results. January 2011 - December 2016, the National Medical Research Center treated 440 patients with cerebral arteriovenous malformations who underwent more than 1200 embolization sessions. From this number, a transvenous access to the AVM was performed in 43 patients. AVMs were localized in the cerebral cortex of 12 patients; in 2 of them (17 %) the transvenous embolization was the single treatment option; the rest of the patients required 2 to 4 preliminary transarterial staged embolizations. In the group, no lethal outcomes and significant persistent neurological deficit were recorded. Total deactivation was achieved in 9 patients (75 %); 2 patients (16.7 %) required microsurgical removal of residual AVM network; in 1 patient (8.3 %), radiosurgical treatment was performed. Discussion. Comparing the results of transvenous treatment of convexital malformations with an of patients treated with the classic transarterial technique, no statistically significant difference (p > 0.05) in morbidity and mortality was achieved. The total occlusion rate of transvenous embolization is significantly higher (p < 0.05). Conclusions. A gradual expansion of indications for the transvenous access increases the efficiency of surgical treatment of this pathology without significantly increasing the risks of adverse outcomes. This access should only be used in centers with significant experience of transarterial embolization.

Functional (conversion) neurological symptoms represent one of the most common situations faced by neurologists in their everyday practice. Among them, acute or subacute functional weakness may mimic very prevalent conditions such as stroke or traumatic injury. In the diagnosis of functional weakness, although elements of the history are helpful, physical signs are often of crucial importance in the diagnosis and positive signs are as important as absence of signs of disease. Hence, accurate and reliable positive signs of functional weakness are valuable for obtaining timely diagnosis and treatment, making it possible to avoid unnecessary or invasive tests and procedures up to thrombolysis. Functional weakness commonly presents as weakness of an entire limb, paraparesis, or hemiparesis, with observable or demonstrable inconsistencies and non-anatomic accompaniments. Documentation of limb movements during sleep, the arm drop test, the Babinski's trunk-thigh test, Hoover tests, the Sonoo abductor test, and various dynamometer tests can provide useful bedside diagnostic information on functional weakness. We therefore present here a brief overview of the positive neurological signs of functional weakness available, both in the lower and in the upper limbs; but none should be used in isolation and must be interpreted in the overall context of the presentation. It should be borne in mind that a patient may have both a functional and an organic disorder.

Purpose: to evaluate the effectiveness of analgesic and anti-inflammatory effects of pterygopalatine blockade in the surgical treatment of cataract in children. Materials and methods. A comparative analysis of the efficacy of intraoperative anesthesia and the course of the postoperative period was carried out in 52 patients of two clinical groups that were formed depending on the method of anesthesia. The first clinical group included 26 patients who underwent a pterygopalatine blockade as a regional component of general anesthesia, the second comparison group was formed of 28 patients undergoing retrobulbar blockade. To assess the adequacy of anesthesia, the concentration of plasma cortisol and oxidation-reduction profile was determined before and after the operation, the intensity of the pain syndrome, the extent of the inflammatory reaction of the eye after surgery were assessed. The results showed a decrease in the concentration of cortisol and increased antioxidant capacity of the organism after surgery in patients of the first group. In patients of the 1^st clinical group, the Tyndal phenomenon of the 1^st degree was revealed in 15.3 % of cases, the remaining patients had no signs of inflammation. Each second patient of 2^nd group had a moderate degree of inflammatory reaction, and in 7 % of cases significant exudative phenomena were noted in the form of the Tyndall II degree phenomenon. Conclusion. The use of vesicle blockade in the surgical treatment of cataracts allowed improving the quality of rehabilitation of a patient with congenital cataract, both in the early and late postoperative period.

Now in practice, the evaluation of the brain condition of a child with perinatal lesions is carried out mainly on the basis of available symptoms and laboratory test data. From hardware diagnostic techniques only neurovisualization is used - MR1, CT and neurosonography. Simple and informative neurophysiological tests, despite the long history of their use, are not used often enough. To objectify the state of neuronal and conducting brain structures, magnetic resonance imaging and the study of auditory brainstem response (ABR) were carried out. The study group consisted of 29 newborn children (10 boys and 19 girls) with perinatal brain lesions. 1n all cases, changes in the structure of the brain tissue on MRI indicate changes in the characteristics of the evoked potential. With signs of damage to myelinated formations, a significant increase in the time parameters of the ABR was noted only in isolated cases (in four children). In 25 cases, the amplitude parameters and the configuration of ABR were varied. Thus, the use of latencies of ABR components as the main source of information for children in the first months of life is inadvisable. The most informative and correlating with the data of MR1 studies are such parameters as the total amplitude level and the splitting of ABR components.

The article presents the results of the study of odontology of the population characteristics in Krasnoyarsk city of XVII-XXI centuries. The aim of this work is to study the main variability dimensions of the molars of the right upper jaw of the population in Krasnoyarsk city in different time frames. For each object of the study, a map of the odontological examination was completed, including the measurement of the mesiodistal and vestibulooral diameters of the right upper jaw molars in the neck and crown regions of the tooth. Based on the results of the measurements, a comparison was made between the average size of the maxilla molars in the population of the city of Krasnoyarsk, depending on gender and the historical period. 131 skulls from osteological series of necropolises ofKrasnoyarsk (73 skulls - Pokrovsky necropolis, XVII-XVIII centuries, 58 skulls - Vsekhsvyatskiy necropolis, XVIII-XIX centuries) and dento-maxillary system of the modern population (68 people) were studied. A biometric study of the size of the molars of the right upper jaw has shown that over the past centuries, residents of the city of Krasnoyarsk experienced an increase in mesiodistal and vestibulo-oral teeth sizes in both men and women. A statistically significant increase in the mesiodistal diameter of the crown and neck of the 16th and 17th teeth was found in all groups of subjects, a statistically significant change in the vestibulooral size was characteristic only of the crown of the first molar of women.

In modern conditions, the justification of managerial decisions in a medical organization requires the introduction of a detailed system of management accounting, the most important element of which is the correctness and legality of writing-off of medical preparations and supplies, especially with respect to resource-intensive types of medical care, in particular, dental care. Purpose of the study: evaluation of the effectiveness of the system of management accounting and reporting developed and implemented in the Department of Therapeutic Dentistry of the ISMU aimed at the rational and effective use of limited financial resources in modern conditions. Methods. The study used an economic method to analyze the actual costs incurred in the provision of dental services in medical organizations in Irkutsk, participating in the provision of medical care in the MH1 system. Results. The use of the developed and implemented system of management accounting and reporting for the dental medical organization on the basis of the results of the implementation for the period January-October 20l7 resulted in a reduction in the actual costs for a single completed case of dental care and almost a twofold reduction in the cost of medicines. However, even the implementation of these measures was not capable of bringing actual expenditures into full compliance with the normative volume of financing in the MH1 system, especially taking into account the phased increase in the level of wages of medics. Conclusion. The internal environment and the accounting and reporting policy of the medical organization are undoubtedly of great importance in solving the problems of rational and effective use of financial resources, but the state's provision of sufficient level of tariffs for medical care in the MH1 system plays a key role.

The lack of a formed professional self-determination among high school students leads to the fact that in the process of medical education and the first years of professional activity, a significant number of students and young specialists leave medicine. Purpose of the study: sociological assessment of professional self-determination of schoolchildren of the upper grades, including those who choose the profession of a doctor, as well as the factors that determine it. Methods. The study was conducted using a sociological survey using a specially developed questionnaire. Results. The level of professional self-determination of schoolchildren of the upper grades is low, one out of every three schoolchildren surveyed has not yet decided on the choice of the future profession, about 8 % of the students have not even chosen an approximate direction of future professional activity. Schoolchildren who have chosen the profession of a doctor, the main motivation is an adherence and a life situation, while prestige and the level of wages are not decisive. As the main base of forming professional self-determination two out of three respondents named the school, meaning the speech made for them by doctors and medical students. For those schoolchildren who have chosen the profession of a doctor on their own, the main motivation factor usually is the visit to the medical university during Doors Open Days. Conclusion. The most important role in the formation of professional self-determination of future doctors belongs to the development and implementation of vocational guidance activities carried out by the forces of the school and medical university.

According to the World Health Organization, in the structure of internal injuries, burns occur in 2.1 per 1000 adults. In practice, all victims after stabilization of the condition are treated surgically with the autodermoplasty, which in the late period is accompanied by a rough scarring, sometimes with the deformation of the damaged area. In addition, infectious complications worsen and aggravate the wound healing process, and also significantly prolong the epithelialization time. A wound is usually infected by opportunistic pathogenic microflora resistant to various groups of antibiotics and antiseptics, by which the affected areas are treated. Modern researches are aimed at finding ways to accelerate regenerative processes of the affected area, to avoid surgical treatment and prevent infection contamination. The object of this study was titanium nickelide supernatant. Currently, there are no published data on the chemical composition of the supernatant, as well as its microbiological safety. This alloy is actively and successfully used in traumatology, dentistry and other fields of medicine. The supernatant was prepared under sterile conditions at a rate of 10 g of titanium nickelide powder per 1 liter of distilled water. In the course of the studies it was proved that nickel and titanium ions are present in the solution, in addition, its bactericidal and bacteriostatic properties are reflected. Thus, the supernatant of nitinol can be used in biological environment and is safe for them.

Background. XXI century is known as a century of obesity and type 2 diabetes (T2D), one of the main reasons of nonalcoholic fatty liver disease (NAFLD). Severe forms of NAFLD, such as non-alcoholic steatohepatitis and cirrhosis, are associated with process of apoptosis. A great contributor in the developing of NAFLD is a dysfunction of hematolymphatic barrier and linagliptin showed positive effect on this. The group of inhibitors of apoptosis - Bcl-2 resists to wide variety of pro-apoptotic proteins. Studying correction of apoptosis can be the key to the treatment of NAFLD, and that is a reason of high interest in anti-apoptotic Bcl-2 protein. Aims. To assess the features of the expression of the anti-apoptotic Bcl-2 protein in the liver of db/db mice in the model of obesity and type 2 diabetes mellitus and with linaglyptin correction. Materials and methods. Experiment was performed on type 11 (db/db) diabetic mice. Linaglyptin or placebo was administered daily by gavage from the 8th to 16th weeks of life. Results. The week immunohistochemical reaction for antiapoptotic protein Bcl-2 was found in placebo-treated mice. Whereas treatment with Linaglyptin shifted the ratio of apoptosis regulators following significant increase in the area of Bcl-2 expression. Conclusions. The obtained results demonstrate a "try" at antiapoptotic activity of the Linaglyptin in the liver in the model of T2D.

It has been determined that exposure to different stressors is associated with the development of oxidative stress, both in animals and in humans. The antioxidant defense system resists the development of oxidative stress. Basidiomycetes are the producers of a variety of biologically active compounds, including triterpene acids, exopolysaccharides, etc. Products derived from these species have immunostimulating, antitumor, antioxidant, antimetastatic action, and are effective for liver diseases treatment. The aim of the study, was to determine the antioxidant activity of Trametin to limit the stress-induced lipid peroxidation process. Antioxidant properties of Trametin (a product obtained by liquid-phase cultivation of the xylotroph fungus Trametes pubescens) were studied under experimental stress (decrease of the lighting intensity in piglets). 1t has been found that Trametin serves as an effective prevention of oxidative stress in stress conditions. 1t increases the level of unsaturation of lipids, reduces the concentration of primary and end products of lipid peroxidation, and also increases the total antioxidant activity of the blood, the activity of superoxide dismutase and reduces the glutathione level. Thus, the study of the effect of the preparation obtained by liquid-phase fermentation from fungus xylotroph of the genus Trametes pubescens showed a pronounced antioxidant effect on the model of dark stress in experimental animals, which can serve as a basis for its further application in veterinary and clinical medicine.

The most common cancer of the endocrine system is thyroid cancer, representing 1.0-1.5 % all newly diagnosed cases of cancer. According to the cancer society of Russia, the thyroid cancer in children is much rarer than in adults. Thyroid cancer in children and adolescents is characterized by an adverse clinical course and a high risk of developing metastases in the lymph nodes. The main method of treatment for pediatric thyroid cancer is total thyroidectomy with central neck lymph node dissection followed by radioactive iodine therapy. In foreign and domestic literature, complications of the organ of vision, namely, changes of the optic disc, after surgical treatment for thyroid cancer are poorly understood. The risk of transient hypocalcemia and hypothyroidism increases after thyroidectomy. In the literature, there are two reported cases of the optic nerve swelling combined with hypoparathyroidism and hypocalcemia. While hypocalcemia intracranial hypertension and swelling of the optic nerves are often recorded. In this article, the authors present their own clinical observation of a 13-year-old patient after thyroidectomy and radioactive iodine therapy with detailed analysis of the clinical data and study results. According to the survey of the patient, bilateral swelling of the optic disc was revealed, which could occur due to hypothyroid state. Objective: to identify the cause of the development of bilateral optic nerve swelling in a patient after thyroidectomy and treatment course with radioactive iodine.