Burdenko National Medical Research Center Research Articles

Cavernomas of cavernous sinus

Background. Cavernoma of cavernous sinus is a fairly rare benign neoplasm, accounting for less than 3 % of all neoplasms in this area. Due to the rarity of this pathology, a standardized protocol for diagnosis or treatment has not been developed. Surgical and radiosurgical methods are used for treatment.Aim. Analysis of the results of treatment of patients with cavernous sinus cavernomas operated at the N. N. Burdenko National Medical Research Center of Neurosurgery from 2000 to 2022 using endoscopic transnasal access.Materials and methods. We present our own experience in the treatment of 9 patients who underwent transnasal endoscopic removal of cavernous sinus cavernoma.Results. A total of about 300 cases of treatment of patients with cavernous sinus cavernomas have been described in the literature, and endoscopic removal has been described in only 12 cases.As a result, subtotal removal was achieved in 7 cases. In 2 cases, the removal was partial. The postoperative period proceeded in all patients without peculiarities and without complications.Conclusion. Endoscopic transnasal access allows partial or subtotal removal of the formation without risk of injury to cranial nerves and with minimal soft tissue injury, which has a positive effect on the postoperative period of patients. In combination with radiosurgical methods, it is possible to achieve satisfactory treatment results.

Comparative analysis of long-term results of surgical treatment of children with basal encephaloceles

Basal encephaloceles (skull base hernias) are a rare pathology manifested by prolapse of altered membranes and brain tissue through a bone defect of the skull base. Endoscopic access is safer and is currently used as the method of choice in the treatment of this pathology. Available literature studies do not cover the quality of life of these patients at follow-up. There is a controversy regarding the impact of endoscopic access on the growth centers of the facial skeleton. Material and methods. A retrospective analysis of a series of 100 patients aged 0 to 18 years with basal encephaloceles who underwent surgical treatment at the N. N. Burdenko National Medical Research Center of Neurosurgery from 2005 to 2022 was carried out to determine the effectiveness and safety of the endoscopic method in the treatment of patients with basal encephaloceles and identify factors affecting the quality of life of these patients. Results and conclusions. Endoscopic endonasal access in the treatment of children with basal encephaloceles is effective and safe. Patients have a high quality of life (>85 points) at follow-up. After the operation, there is an improvement in nasal breathing and an increase in the degree of psychomotor development. Patients have a high quality of life (>85 points) at follow-up. A lower quality of life at follow-up was observed in children with delayed psychomotor development before surgery (OR=0.6; p=0.003). The follow-up study of the dynamics of craniometric parameters did not reliably show any disturbances in the growth of the bones of the facial skeleton in patients after endoscopic surgery.

Neuroradiological characteristics of hydrocephalus due to idiopathic extraventricular CSF pathways obstruction

The development of research on CSF flow disorders made it possible initially to divide hydrocephalus into «communicating» and «non-communicating», and subsequently to distinguish the concepts of «intraventricular» and «extraventricular» obstruction. Improvement of radiological imaging technologies has allowed determining the exact level of CSF obstruction. In some cases, CSF flow disorders combine signs of different forms of hydrocephalus. Their correct classification allows selecting the type of surgical treatment, which reduces the rate of complications and patient»s dependence on the doctor. Purpose of the research: To study the radiological signs of hydrocephalus in idiopathic obstruction at the level of the posterior cranial fossa cisterns. Materials and methods. This study included adult patients (18 years old and over) whose disease was idiopathic in nature. From 2007 to 2020, 289 patients diagnosed with idiopathic hydrocephalus were treated at the N. N. Burdenko National Medical Research Center of Neurosurgery. Of these, 65 patients (18.7 %) had clinical and radiological signs of extraventricular obstruction. The male to female ratio was 25 and 40 (38.5 % and 61.5 %), respectively. A variety of radiological signs were assessed and their origin and occurrence in various forms of idiopathic hydrocephalus were determined. Results. FOHR was the highest (compared with other forms of idiopathic hydrocephalus (mean 0.52)). Other ventricular indices were also high. None of them correlated with the patient»s condition. Ventral dislocation of the premamillary membrane was detected in 89.2 %. Turkish saddle was of normal size in 51 (78.4 %) patients, while its enlargement was found in 13 (20 %) patients. A change in the periventricular signal was noted in 18.4 %. Aqueduct and IV ventricle outlets were patent in all cases as evidenced by CSF pulsation artifacts in T2 3D CUBE. The cerebral aqueduct was dilated in 63 (96.9 %) patients. Enlargement of the cisterna magna associated with hypotrophy of the caudal cerebellum was noted in 90.7 %, and this sign was significant for extraventricular cisternal obstruction (p <0.001). In addition to the T2 mode, the presence of sagittal sections in cisternography modes (FIESTA or CISS) was a prerequisite. By means of these modes, the ventral dislocation of the premamillary membrane was more clearly visualized, the presence of obstacles to the CSF flow in the cerebral aqueduct was excluded, and, most importantly, it was possible to determine the presence of additional membranes in the subarachnoid spaces between the ventral surface of the brain stem and the clivus. These were found in 100 % of the patients, which was also a significant pathognomonic sign (p < 0.001). Conclusion. The MRI picture of hydrocephalus with obstruction at the level of the posterior cranial fossa cisterns has specific signs. It combines the signs of other forms of hydrocephalus, chronic disease in combination with symptoms of the CSF pathways obstruction. It can be classified into a separate form and both endoscopic and shunt surgery can be used for treatment.

Clinical picture of hydrocephalus due to extraventricular cisternal CSF pathways obstruction

Introduction. The variety of clinical symptoms of hydrocephalus due to obstruction at the level of the posterior cranial fossa cisterns, or extraventricular obstructive hydrocephalus (EVOH), frequently goes against radiological semiotics and causes difficulties in developing patient management tactics.Materials and methods. Analysis of 65 patients treated for idiopathic hydrocephalus due to cisternal CSF pathways obstruction at the FSAI N. N. Burdenko National Medical Research Center of Neurosurgery of the Ministry of Health of Russia. All symptoms the patients complained of, which could be caused by hydrocephalus, were evaluated. Results. Extraventricular obstructive hydrocephalus has a longer history of illness compared to other forms of hydrocephalus and averages almost 4 years. The most common symptoms of the onset of the disease are headaches (41.5 %) and gait disturbances (29.2 %). When diagnosing, the main symptoms of the disease are gait disturbances (76.9 %), memory loss in relation to current events (76.9 %), headache (63 %), and pelvic disorders in the form of incontinence (46.1 %). Dizziness, nausea, arm tremor, amenorrhea, vomiting, pyramidal symptoms, and syncope are significantly less common. The clinical picture of patients under 60 years is characterized by common cerebral symptoms and mild signs of the Hakim-Adams syndrome. However, there is a different dependence for elderly patients. Endoscopic or shunt surgery can help to achieve complete or partial recovery. Conclusion. Thus, the EVOH clinical picture is diverse and often has completely non-specific manifestations, which match the anatomical changes in different brain structures according to MRI, but the sequence of occurrence of some symptoms is not explained. Each of the EVOH clinical manifestations, individual or in combination with other symptoms, should be considered as an indication for surgical treatment.

Classification of intracranial tumors based on optical-spectral analysis

The motivation for the present study was the need to develop methods of urgent intraoperative biopsy during surgery for removal of intracranial tumors. Based on the experience of previous joint work of GPI RAS and N.N. Burdenko National Medical Research Center of Neurosurgery to introduce fluorescence spectroscopy methods into clinical practice, an approach combining  various optical-spectral techniques, such as autofluorescence spectroscopy, fluorescence of 5-ALA induced protoporphyrin IX, diffuse reflection of broadband light, which can be used to determine hemoglobin concentration in tissues and their optical density, Raman spectroscopy, which is a spectroscopic method that allows detection of various molecules in tissues by vibrations of individual characteristic molecular bonds. Such a variety of optical and spectral characteristics makes it difficult for the surgeon to analyze them directly during surgery, as it is usually realized in the case of fluorescence methods – tumor tissue can be distinguished from normal with a certain degree of certainty by fluorescence intensity exceeding  a threshold value. In case the number of parameters exceeds a couple of dozens, it is necessary to use machine learning algorithms  to build a intraoperative decision support system for the surgeon. This paper presents research in this direction. Our earlier statistical analysis of the optical-spectral features allowed identifying  statistically significant spectral ranges for analysis of diagnostically  important tissue components. Studies of dimensionality reduction techniques of the optical-spectral feature vector and methods of clustering of the studied samples also allowed us to approach the implementation  of the automatic classification method. Importantly, the classification task can be used in two applications  – to differentiate between different tumors and to differentiate between different parts of the same (center, perifocal zone, normal) tumor. This paper presents the results of our research in the first direction. We investigated the combination of several methods and showed the possibility of differentiating glial and meningeal tumors based on the proposed optical-spectral analysis method.

Surgical aspects of classification and neuroimaging characteristics of idiopathic hydrocephalus in adults

Background. Hydrocephalus can be developing by a traumatic brain injury, intracranial hemorrhage, tumor, meningitis of congenital malformation of the central nervous system. When the cause of the hydrocephalus is unclear it is supposed as idiopathic hydrocephalus. The most important classification features are the etiology and level of CSF obstruction. The classification was improved and developed with diagnostic and surgical methods simultaneously. Currently, the neurosurgeons have the possibility for usage of various methods and techniques of surgical treatment with their advantages and disadvantages. Systematization of radiological parameters is necessary to make a decision about the type of the surgery.Aim. To analyze and systematize the neuroimaging characteristics of various forms of idiopathic hydrocephalus in adults, to assess the possible classification of idiopathic hydrocephalus.Materials and methods. Between October 2011 and March 2021 290 patients with idiopathic adult hydrocephalus were operated at the N.N. Burdenko National Medical Research Center of Neurosurgery of the Ministry of Health of Russia: onset of symptoms in adulthood; no indications of the etiology of hydrocephalus and congenital hydrocephalus. The age of the patients was 50 ± 18.2 (18–85) years. The magnetic resonance images of patients were evaluated for the size of the ventricles, condition of convexital and basal subarachnoid spaces, obstruction of the CSF pathways, and changes in the position of the premamillary membrane, septum pellucidum, the roof of the 3rd ventricle and the tonsils of the cerebellum, the size of the sella turcica, the angle of the corpus callosum. The frequency of each of these parameters is statistically estimated for each form of idiopathic hydrocephalus.Results. Aqueduct stenosis has become the most frequent form of idiopathic hydrocephalus. Hydrocephalus in obstruction of the foramen of Monroe, aqueduct, foramen of Magendie, and cisterns of the posterior cranial fossa was significantly more characteristic of young people (p <0.05). Hydrocephalus with obstruction of convexital CSF spaces can be called hydrocephalus of the elderly (p <0.001). Hydrocephalus without verified signs of occlusion CSF pathways occurs equally in all age groups. The FOHR index was significantly more important, and only in case of cisternal obstruction. Enlargement one or both lateral ventricles and flattening of the roof of the 3rd ventricle is characterized for Monro’s foramen obstruction (p <0.001). The membrane at the outlet of the 4th ventricle and the absence of the “flow void” was typically only for patients with obstruction of the foramen of Magendie (p <0.001). Ventral dislocation of the premamillary membrane was characteristic of obstruction of the cerebral aqueduct, the foramen of Magendie, and cisterns of the posterior cranial fossa. Compression of the convexital CSF spaces occurred in case of obstruction of the aqueduct, the foramen of Magendie, but CSF spaces of the posterior cranial fossa – only with obstruction of the foramen of Magendie. Dilation of the 4th ventricle was significantly associated with obstruction of the foramen of Magendie and cisterns of the posterior cranial fossa (p <0.05). DESH symptom was significantly associated with obstruction of convexital CSF spaces (p <0.001). Additional membranes in the cisterns of the posterior fossa were found only in cases of cisternal obstruction (p <0.001). Cerebellar tonsils herniation was observed with obstruction of the foramen of Monroe, cerebral aqueduct, and foramina of Magendie.Conclusion. Because of statistical analysis, general signs found in all types of hydrocephalus, and private ones, characterizing only specific signs of the type of the disease, both were found. The classification is logical and justified, it is well applicable in neurosurgical and radiological practice. It allows rational planning of diagnostic evaluation and treatment of patients. A modern magnetic resonance imaging protocol should include T2 scans (with “flow void”) and FIESTA/CISS scans in the required planes, axial FLAIR scans.

The relation of changes in intraoperative EEg and ECog with age, anamnesis duration and outcome of surgical treatment in children with symptomatic epilepsy

   Aim. To reveal relation of change in intraoperative electroencephalography (EEG), electrocorticography (EсoG) with age of patients, the anamnesis duration, localization and type of pathology, the result of treatment.   Materials and methods. 64 patients with symptomatic epilepsy operated at N.N. Burdenko National Medical Research Center of Neurosurgery of the Ministry of Health of Russia from 2010 to 2016. 28 males, 36 females, age from 3 months to 18 years, on average 7,2 years. The pathology localization: temporal – 21 cases, occipital and parietal – 18, frontal – 25. Pathomorphology: 12 patients with focal cortical dysplasia (FCD) I, 20 patients with FCD II, 5 patients with FCD III, 4 patients with tuberous sclerosis, 20 patients with low grade tumors, and 3 cases else. The duration of diseaseis from 61 to 5081 days. Catamnesis (follow-up) ranged from 364 to 1877 days. There was four criteria for including patients in research: intraoperative EEG, presence of initial and control registration of EсoG, follow-up above 364 days. There are three hallmarks selected as significant concerning the efficiency of neurophysiological monitoring: 1) the positive changes in scalp EEG: decrease of interhemispheric asymmetry due to reduction of slow activity on the side of pathology; significant reduction of the unilateral epileptiform activity on the side of pathology and bilateral if exist; 2) the positive changes in EсoG: significant reduction of the regular epileptiform activity; 3) the absence or existence of residual epileptiform activity in adjacent to resected pathology sites. The statistical processing carried out with application of a Stat10 package.   Results. The more expressed positive dynamics of EEG were revealed in patients of smaller age already during operation. A correlation was found between the age of patients and the positive dynamics of intraoperative EEG. An inverse correlation was found between the duration of the disease and the positive dynamics of the scalp EEG during surgery (p = 0.1560). The EEG changes during surgery were shown more often with reduction of the seizure anamnesis. There was found out that residual epileptiform activity on ECoG occurred more often at patients with longer anamnesis of a disease and at patients with frontal localization of pathology. The residual epileptiform activity on ECoG was registered more often at patients with preservation of seizures (outcomes 2, 3, 4, 5 ILAE).   Conclusions. During resective interventions for symptomatic epilepsy in children the probability of positive changes was the more, the younger the patient was. Intraoperative ECoG is one of the useful tools in epilepsy surgery, but it does not definitely determine success. There was no statistically significant relationship between the presence of residual epileptiform signs on the ECoG in the cortex adjacent to the removal area and the outcome of surgical treatment for seizures. Patients in follow-up had three times fewer seizures in the absence of residual epileptiform activity on the ECoG of adjacent to the resected areas of the cortex. The dependence is statistically insignificant. Removal of FCD type III and tumors is accompanied by a more complete elimination of epileptiform activity than FCD I, the level of statistical significance of p = 0.0305.

Применение интраоперационной навигации в эндоскопической эндоназальной хирургии мукоцеле околоносовых пазух

Objective. Evaluation of the effectiveness, safety, and benefit of the use of electromagnetic computer navigation in endoscopic endonasal surgery of paranasal mucocele. Materials and methods. At the Burdenko National Medical Research Center, from 2019 to 2022, 30 endoscopic endonasal removal of paranasal mucocele were performed: 10 operations were performed under CT-guided navigation, 12 with CT-MRI navigation, and 8 without navigation. The clinical findings of the disease, the history of life of patients, the data of endoscopic examination of the nasal cavity, olfactometry, intraoperative parameters, recurrence rate of the mucocele were analyzed. Results. Localization of the mucocele in the frontal sinus was significantly more common in the groups using navigation (p = 0.044). According to olfactometry before surgery, anosmia on the side of the pathology was more often detected in patients in groups using navigation (p = 0.005). According to endoscopy before surgery, scarring in the nasal cavity was found only in groups using navigation. There were no intraoperative complications in the three groups. The average intraoperative blood loss in the three groups did not differ significantly. The duration of the operation was slightly longer in the groups using navigation. The median navigation setup time in the CT navigation group was 8.5 [7.3; 9.8] min, in the CT-MRI navigation group it was 7.5 [7.0; 8.3] min. The median error in each group was 0 mm. According to the operating surgeon, computer navigation was necessary and the most beneficial in 100% of cases. The median long-term follow-up was 746 [478.3; 1133.0] days in the non-navigation group, 673 [176.0; 791.0] days in the CT-navigation group, and 274 [195.5; 371.0] days in the CT-MRI navigation group. Conclusion. The use of intraoperative navigation is justified in endoscopic debridement of mucocele with destruction of the walls of the orbit and the base of the skull, with scarring in the nasal cavity. The use of CT-MRI navigation is useful in a case of scarring in the nasal cavity and deformation of the orbit walls in the case of a fronto-orbital mucocele as well as while removing a sinonasal neoplasm bordering on the mucocele.

Radicality of lateral ventricular neoplasms removal and risk factors of postoperative hemorrhagic complications

Introduction. Lateral ventricular neoplasms (tumors, vascular neoplasms, cysts) are rare and according to different sources comprise between 0.64 and 3.5 % of all brain tumors. Due to relatively slow growth, tumors can reach significant size before patient develops neurological symptoms. Surgery is the main method of treatment of lateral ventricular neoplasms, and in many cases radical removal can be achieved. The main complications after surgery are hydrocephalus and hemorrhages. The later frequently lead to escalation of neurological symptoms and sometimes require repeat surgical intervention. The success of intraventricular surgery consists of reasonable radicality and absence of complications.Aims. To evaluate the radicality and safety of lateral ventricular tumor removal through traditional approaches–transcallosal and transcortical – using arterial spin labeling (ASL perfusion) and to analyze the risk of hemorrhagic complications in the early postoperative period in the context of tumor location and blood supply.Materials and methods. At the N.N. Burdenko National Medical Research Center of Neurosurgery between 2017 and 2019 48 patients with space‑occupying lesions of the lateral ventricles were examined and treated with surgery. All patients were examined using the same MRI protocol before and after surgery: Т1‑weighted, Т1‑weighed contrast‑enhanced, 3D SPGR, Т2‑weighted, Т2‑FLAIR, DWI, T2‑FLAIR CUBE, SWAN, ASL perfusion. In 28 (58 %) cases, transcortical approach was used (through the frontal lobe in 24 cases, through the upper temporal lobe in 2 cases, through the parietal lobe in 2 cases); transcallosal approach was used in 16 (33 %) cases; combination approach (for advanced tumors of the lateral ventricles) was used in 3 (6 %) cases; supracerebellar infratentorial approach was used in 1 (2 %) case. Radicality of lateral ventricular tumor removal and risk factors for postoperative hemorrhagic complications using different approaches were evaluated based on the following parameters: tumor volume and location, sex, blood flow characteristics, presence of hydrocephalus.Results. In the compared groups I and II, similar rates of radical tumor removal were observed: 63 % for transcortical approach and 71 % for transcallosal approach. Hematomas in the tumor bed were more frequently observed in patients operated through transcortical approach (64 % vs. 31 % in transcallosal) without statistical significance. Generally, there were no statistically significant differences between surgical treatment results in groups I and II (p >0.05); this conclusion was confirmed in pseudo‑randomized patient subgroups selected through propensity score matching. Analysis of the association between hematoma in the postoperative period and baseline blood flow level showed that in the group with such hematomas mean tumor blood flow prior to surgery was almost twice as high as in the group without hemorrhagic complications after resection (80.6 vs. 49.4 ml/100 g/min, respectively).The following postoperative parameters are statistically significant for development of hematoma in the tumor bed: presence of hydrocephalus, Evans index in the early postoperative period.Conclusions. Correct and adequate choice of surgical approach considering anatomical location and advancement of the tumor, presence of hydrocephalus and surgeon’s preferences ensures high radicality of removal. Factors affecting the risk of hemorrhagic complications in the early postoperative period should be taken into account: sex, presence of hydrocephalus, neoplasm location and blood flow level.

Surgical treatment of adenoid cystic carcinomas of sinonasal localization

Background. Tumors of the sinonasal region represent a large group of both benign and malignant formations affecting the nasal cavity, paranasal sinuses, structures of the anterior and middle cranial pits of the base of the skull.Aim. Evaluation of the results of surgical treatment of patients with adenoid cystic carcinomas of sinonasal localization treated in the period from 2007 to 2021.Material and methods. The present study is a retrospective analysis of the results of surgical treatment of patients with adenoid cystic cancer of the base of the skull operated at the N.N. Burdenko National Medical Research Center of Neurosurgery in the period from 2007 to 2021.Results. The radicality of tumor removal was assessed based on an MRI analysis performed no earlier than 3 months after surgery. Total (95–100 %) tumor removal was achieved in 8 (25 %), subtotal (80–95 %) in 15 (46.9 %), partial (50–80 %) in 5 (15.6 %) patients; extended biopsy was performed in 4 (12.5 %) cases. At the same time, total and subtotal removal was more often achieved with open surgery, which was due to the topographic and anatomical features of the location of tumors.Discussion. In this paper, we present an analysis of the results of treatment of 32 patients with adenocystic cancer of sinonasal localization.The main method of treatment is an integrated approach – radical surgical resection of the tumor together with adjuvant radiation therapy. Surgical treatment is aimed at the maximum possible resection of pathological tissues to prevent recurrence of the disease.One of the most common approaches is transfacial with or without bifrontal craniotomy, which includes craniofacial resection.Conclusion. Adenoid cystic carcinoma is an aggressive malignant tumor that requires a comprehensive approach to treatment. Important factors that positively affect the results of treatment are the conduct of chemoradiation treatment and the age of patients, as well as the initial stage of the disease at which treatment was initiated, which necessitates strengthening dispensary monitoring and raising awareness of the population about the possibility of developing such diseases for timely access to a doctor.

Classical trigeminal neuralgia recurrence after vascular decom - pression: analysis of the causes and features of the clinical picture

Introduction. Pain syndrome recurrence in patients with classical trigeminal neuralgia (CTN) after surgical treatment is an important and relevant issue, despite the advances in the diagnosis of the disease, progress in approaches to patient selection, and proven surgical tactics. The aim of the study is to evaluate the affecting factors for redo surgery in patients with CTN recurrence. Materials and methods. 257 patients with CTN recurrence operated on at the FSAI N.N. Burdenko National Medical Research Center for Neurosurgery of the Ministry of Health of the Russian Federation for the period from 2012 to 2017 were involved in the prospective nonrandomized study. Intraoperative findings and pain structure in postoperative period were evaluated in patients after revision surgery. Burchiel classification, DN4 Questionnarie, and Barrow Neurological Institute Pain Intensity Score (BNI-PS) were used. Results. CTN recurrence in the early and late post-operative periods was registered in 33 patients, which accounted for 13% of the total number of patients in the study group. 58% of them underwent secondary surgical intervention. The efficacy of redo surgery was noted in 79% of patients with complete regression of pain. Patients with CTN and neuropathy combination were admitted to alternative methods (neuromodulation, radiosurgery, radiofrequency ablation). In patients who received stimulation of the branches of the trigeminal nerve after vascular decompression, pain regression was observed in 100% of cases. Patient distribution after combined treatment was 78% for BNI-PS score I and 22% for BNI-PS score 2-3, respectively. Conclusion. In patients with “pure” CTN recurrence, redo surgery presents an effective method of treatment. In patients with CTN and neuropathy combination, repeat vascular decompression is effective only in terms of paroxysmal pain. Thus, multidisciplinary approach is needed – combining adjunctive methods of treatment in neurology, neurosurgery, pain management, and radiotherapy.

Use of complementary medicine in autoimmune diseases of the nervous system

The relevance of the study is due to the lack of complete understanding of the formation of psychopathological symptoms in trigeminal neuralgia (TN) in dynamics before and after surgical treatment. Moreover, currently, there is no algorithm for conducting psychotherapeutic measures for TN patients. The purpose of the study: Examination of psychic disorders in TN patients. Methods: Severity of anxiety, depression, obsessive and phobic disorders, the duration of pain persistence after surgery, and accentuation of personality were assessed in 39 TN patients operated in the N. N. Burdenko National Medical Research Center for Neurosurgery during 2012–2014. Results: Psychic disturbances probability increased in direct proportion to the duration of the pain syndrome. Mental disorders in TN were significantly more likely to occur in psychopathically or characterologically accentuated individuals. The main psycho-emotional manifestations in patients before and after surgery for TN include varying degrees of emotional stress. A high degree of emotional stress was detected in 55 % of patients, moderate — in 35 %, mild — in 10 % of patients. During the follow-up study, it was found that the majority of patients defined their condition as good and satisfactory. Pain syndrome was not detected in 71 % of patients. The examination of the mental state in 71 % of cases did not reveal any changes, while in 14 % of cases the disorders were episodic.

Monitoring of corticobulbar motor evoked potentials during surgical remov¬al of brainstem and fourth ventricle tumors in pediatric patients

Introduction. Corticobulbar motor evoked potentials (CB-MEP) are a modality of intraoperative monitoring (IOM) for assessment of the functional state of caudal cranial nerves. CB-MEPs can be used during fossa posterior surgery, when there is a risk of damaging the caudal cranial nerves and their nuclei. The possibility of using this modality in pediatric patients is rarely discussed in the literature. Objective. To assess the CB-MEP validity in the prognosis of neurological symptoms from caudal cranial nerves in the pediatric group of patients after surgery in the brainstem and fourth ventricle. Material and methods. The study included 30 children aged from 11 months to 17 years who underwent brainstem and the fourth ventricle tumor surgery with IOM at the N.N. Burdenko National Medical Research Center for Neurosurgery from January 2020 to November 2021. Results. We obtained statistically significant difference in the dynamics of the CB-MEP amplitude in the groups of patients with and without an increase in neurological symptoms (p<0.05). Conclusion. CB-MEP can be used during brainstem surgery in pediatric patients for assessing the functional state of caudal cranial nerves.

Historical accuracy: determination of the foundation date of the Institute – National Center for Neurosurgery

Study of the documents from 1928–2015 allowed to determine historically accurate date of foundation of the National Center for Neurosurgery. On this date, due to the initiative from N. N. Burdenko and V. V. Kramer and according to the Decree of the Small Council of the Peoples’ Commissars of the RSFSR, the first Moscow neurosurgical clinic under the State Roentgen Institute opened its doors. Note in the preserved operation journal of the clinic states that the first patient was operated on by N. N. Burdenko on February 15th, 1929. In the context of surgical facilities, the date of first surgery is considered the date of their opening.In 1932, the Scientific Research Neurosurgical Institute was established at the first neurosurgical clinic which in 2015 in accordance with the Decree of the Government of the Russian Federation was transformed into the N. N. Burdenko National Medical Research Center for Neurosurgery.

Surgical treatment of patients with idiopathic obstruction of the foramen of Monro

Introduction. Idiopathic obstruction of the foramen of Monroe is an extremely rare pathology in adults and accounts for 1 % of all forms of occlusive hydrocephalus. The largest described series of patients with such pathology includes 4 adult patients. Four types of the foramen of Monro obstruction have been distinguished: type A – atresia, or stenosis, type B – morphological obstruction (membrane), type C – functional obstruction, type D – patent foramen. These patients usually undergo endoscopic or shunting surgery. Currently no algorithm exists for the treatment of such patients.Materials and methods. From 2004 to 2019 year 251 adult patients with idiopathic hydrocephalus were treated at the N. N. Burdenko National Medical Research Center of Neurosurgery. Of these, 11 people (4.4 %) had signs of obstruction at the level of the foramen of Monro. The average age of the patients was 41.9 years (25–67 years). The condition was more prevalent among women (8 female, 3 male patients). The most common symptoms were headaches and nausea. None of the patients showed signs of intracranial hypertension upon examination of the fundus. Magnetic resonance imaging of the brain demonstrated expansion of one or both of the lateral ventricles, stenosis of foramina of Monro, or their occlusion by membranes.Results. Patients were divided into 3 groups depending on the type of foramen of Monro obstruction. Type A obstruction was observed in 8 patients: in patients with unilateral obstruction (3 patients), only septostomy was performed, while among the patients with bilateral obstruction, 3 patients underwent septostomy followed by reconstruction and stenting of the right foramen of Monro (1 of these patients later required a shunting procedure), and in 2 patients, a shunting procedure was performed at initial presentation. Type B obstruction was observed in 2 patients: a patient with unilateral obstruction underwent septostomy and dissection of the membrane, and 1 patient with bilateral obstruction underwent septostomy, dissection of the membrane, and foraminal stenting. In a patient with type C obstruction, a septostomy and stenting of the right foramen of Monro were performed. Based on postoperative MRI data, the dimensions of the ventricles of the brain decreased or did not change. Most patients showed a complete regression of symptoms or their significant reduction, while one patient’s condition stabilized after surgery. There were no fatal outcomes or persistent complications. The follow-up period ranged from 4 to 60 months (29.4 months on average).Conclusion. In cases of idiopathic obstruction of the foramen of Monro, endoscopic surgery can be used as the treatment of choice.

Differential diagnosis of pneumonia as a complication of nasal liquorrhea in the context of the COVID-19 pandemic: Case report

Nasal liquorrhea the outflow of cerebrospinal fluid from the cerebrospinal fluid spaces of the cranial cavity into the nasal cavity or paranasal sinuses due to the presence of a congenital or acquired defect in the bones of the skull base and meninges of various etiologies. Nasal liquorrhea leads to potentially fatal complications: meningitis, meningoencephalitis, pneumocephalus, brain abscess. Also, with nasal liquorrhea, less dangerous complications may occur: aspiration bronchopneumonia and gastritis. The article presents a case of aspiration pneumonia in two patients with nasal liquorrhea treated at the Burdenko National Medical Research Center for Neurosurgery during the COVID-19 pandemic. Both patients noted the profuse nature of the nasal liquorrhea, complained of coughing in a horizontal position. In both cases, no RNA virus (SARS-CoV-2) was detected during the polymerase chain reaction. Antibodies (IgG, M) to coronavirus were not detected. Computed tomography of the chest organs in both cases revealed areas of frosted glass darkening. Since no data was obtained for coronavirus infection (negative tests for coronavirus, lack of antibodies), changes in the lungs were interpreted as a consequence of constant aspiration of CSF. The patients were admitted to a separate ward. Both patients underwent endoscopic endonasal plasty of the skull base defect. The postoperative period in both cases was uneventful. In both cases, the patients underwent computer tomography scan of the chest organs one month later. On the photographs, the signs of pneumonia completely regressed.

Analysis of computed tomography scans for development of differentiated approach to repair of ethmoid roof defects

Study of the images before surgery in order to analyze the individual characteristics of the anatomy is the key to a successful surgery. Materials and Methods: Analysis of computed tomography data of 43 patients with defects in the ethmoid roof operated from 2010 to 2020 at the Burdenko National Medical Research Center for Neurosurgery. Patients were divided into two groups according to the localization of the defect and relapses. Results. With anterior defects, the angle between the line drawn through the nasal dorsum and the perpendicular drawn through the center of the defect to the bottom of the cavity is sharper than with posterior ones, p < 0.001. The height from the bottom of the nasal cavity to the ethmoid roof was greater with anterior defects than with posterior defects (p = 0.011). The height from the bottom of the nasal cavity to the cribriform plate with anterior defects is greater than with posterior ones (p = 0.006). When analyzing the ratio of the height of the middle turbinate and the distance from the septum to the orbit and when determining the length of the lattice roof anteriorly or posteriorly from the basal lamella, depending on the location of the defect with the length of the middle turbinate, it was found that the differences were statistically significant (p < 0.05). Conclusions. The posterior parts of the ethmoid roof are more likely to develop iatrogenic defects due to their lower location in relation to the bottom of the nasal cavity. For the correct choice of optics and instruments, the angle between the line drawn through the nasal dorsum and the perpendicular drawn through the center of the defect to the bottom of the nasal cavity matters. A middle turbinate flap can be used to seal both anterior and posterior ethmoid roof defects. The anatomical features of the ethmoid roof do not affect the incidence of relapses.

[MR-guided non-invasive typing of brain gliomas using machine learning].

To evaluate diagnostic accuracy of deep learning methods for glioma typing according to the 2007 WHO classification based on preoperative magnetic resonance imaging (MRI) data. The study included MR scans of patients with glial tumors undergoing neurosurgical treatment at the Burdenko National Medical Research Center for Neurosurgery. All patients underwent preoperative contrast-enhanced MRI. 2D and 3D MR scans were used for learning of artificial neural networks with two architectures (Resnest200e and DenseNet, respectively) in classifying tumors into 4 categories (WHO grades I-IV). Learning was provided on 80% of random examinations. Classification quality metrics were evaluated in other 20% of examinations (validation and test samples). Analysis included 707 contrast-enhanced T1 welghted images. 3D classification based on DenseNet model showed the best result in predicting WHO tumor grade (accuracy 83%, AUC 0.95). Other authors reported similar results for other methods. The first results of our study confirmed the fundamental possibility of grading axial contrast-enhanced T1 images according to the 2007 WHO classes using deep learning models.

Best Research Practice Implementation: The Experience of the N.N. Burdenko National Medical Research Center of Neurosurgery.

Implementing the best research principles initiates an important shift in clinical research culture, improving efficiency and the level of evidence obtained. In this article, we share our own view on the best research practice and our experience introducing it into the scientific activities of the N.N. Burdenko National Medical Research Center of Neurosurgery (Moscow, Russian Federation). While being adherent to the principles described in the article, the percentage of publications in the international scientific journals in our Center has increased from 7% to 27%, with an overall gain in the number of articles by 2 times since 2014. We believe it is important that medical informatics professionals equally to medical experts involved in clinical research are familiar with the best research principles.

External Ventricular Drainage Complication Risks and Accuracy Analysis

The setting of external ventricular drainage (EVD) is one of the most frequent procedures in the neurosurgical practice. However, complication risks of this procedure may grow from 5% to 39%. The number of publications concerning the advancement of ventricular drainage setting technique and complication risks identification is increasing year after year. We posed a question on the dependence of complication risks and catheter setting accuracy on the different factors of routine practice of the N. N. Burdenko National Medical Research Center for neurosurgery within the scope of this work. The data on patients whose EVD was set in the premotor area in 2019 were collected retrospectively. The surgeons were divided into 3 groups according to their experience valued in years. The result of drainage setting was considered satisfactory if its end was in the frontal horn or body of the ipsilateral ventricle. Generally, 122 patients passed EVD placement during 2019. According to computed tomography scans of the brain, the drainage position was satisfactory in 85 patients (75.9%) and unsatisfactory in 27 patients (24.1%). The procedures were performed by surgeons with <2 years of experience in 16.1% of cases, 2-5 years of experience in 25% of cases, and >5 years of experience in 58.9% of cases. The complication risk and accuracy of drainage setting do not depend on surgeon experience, type of bone access, and position in the premotor area.