[MR-guided non-invasive typing of brain gliomas using machine learning]. / Pervye rezul'taty neinvazivnogo tipirovaniya gliom golovnogo mozga po dannym magnitno-rezonansnoi tomografii s pomoshch'yu mashinnogo obucheniya.

Gliomas are the most common neuroepithelial brain tumors. The modern classification of tumors of central nervous system and treatment approaches are based on tissue and molecular features of a particular neoplasm. Today, histological and molecular genetic typing of tumors can only be carried out through invasive procedures. In this regard, non-invasive preoperative diagnosis in neurooncology is appreclated. One of the perspective areas is artificial intelligence applied for neuroimaging to identify significant patterns associated with histological and molecular profiles of tumors and not obvlous for a specialist. OBJECTIVE: 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. MATERIAL AND METHODS: 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). RESULTS: 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. CONCLUSION: 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.

[Artificial intelligence technologies in clinical neurooncology]. / Tekhnologii iskusstvennogo intellekta v klinicheskoi neiroonkologii.

Neurooncology in the 21st century is a complex discipline integrating achievements of fundamental and applied neurosciences. Complex processes and data in clinical neurooncology determine the necessity for advanced methods of mathematical modeling and predictive analytics to obtain new scientific knowledge. Such methods are currently being developed in computer science (artificial intelligence). This review is devoted to potential and range of possible applications of artificial intelligence technologies in neurooncology with a special emphasis on glial tumors. Our conclusions may be valid for other areas of clinical medicine.

[Risk factors of nosocomial meningitis in neurological intensive care unit. Results of a five-year prospective study]. / Faktory riska razvitiya nozokomial'nykh meningitov u patsientov neirokhirurgicheskogo profilya v otdelenii reanimatsii i intensivnoi terapii. Rezul'taty pyatiletnego prospektivnogo issledovaniya.

Nosocomial meningitis (NM) is a serious complication in neurosurgery. Understanding the risk factors of nosocomial meningitis is important for their prevention. OBJECTIVE: To determine the main risk factors of NM in neurological intensive care unit. MATERIAL AND METHODS: A prospective study included all patients (n=2140) treated at the neurological intensive care unit for more than 48 hours between October 1, 2010 and October 31, 2015. Cases of nosocomial meningitis were registered. We analyzed risk factors in 2 groups of patients (with and without NM). RESULTS AND DISCUSSION: The incidence of NM in neurological intensive care unit was 8.4% (95% CI 6.8-10.0) (n=180). Relative risk of NM under external ventricular drainage was 3.98 (99 cases of NM, p<0.05). Relative risk of NM in patients with CSF leakage (including nasal CSF leakage after transsphenoidal surgery) was 5.2 (49 cases of NM, p<0.05). The incidence of nosocomial meningitis was significantly higher among patients with surgery time ≥8 hours (17.68%, p<0.01). Nosocomial meningitis was also significantly more common after redo surgery (13.07%, p<0.05). Insertion of intracranial pressure sensor was not a significant risk factor of NM. The risk of meningitis was 2.67% if the above-mentioned factors were absent. Extracranial factors are not specific for NM. No significant relationship between certain neurosurgical disease and NM was found. CONCLUSION: We found higher risk of NM in ICU patients with the following factors: external ventricular drainage, CSF leakage, redo surgery and surgery time.

Artificial Intelligence in Neurosurgery: a Systematic Review Using Topic Modeling. Part I: Major Research Areas.

In recent years, the number of scientific publications on artificial intelligence (AI), primarily on machine learning, with respect to neurosurgery, has increased. The aim of the study was to conduct a systematic literature review and identify the main areas of AI applications in neurosurgery. METHODS: Using the PubMed search engine, we found and analyzed 327 original articles published in 1996-2019. The key words specific to each topic were identified using topic modeling algorithms LDA and ARTM, which are part of the AI-based natural language processing. RESULTS: Five main areas of neurosurgery, in which research into AI methods are underway, have been identified: neuro-oncology, functional neurosurgery, vascular neurosurgery, spinal neurosurgery, and surgery of traumatic brain injury. Specifics of these studies are characterized. CONCLUSION: The information presented in this review can be instrumental in planning new research projects in neurosurgery.

Artificial Intelligence Technologies in Neurosurgery: a Systematic Literature Review Using Topic Modeling. Part II: Research Objectives and Perspectives.

The current increase in the number of publications on the use of artificial intelligence (AI) technologies in neurosurgery indicates a new trend in clinical neuroscience. The aim of the study was to conduct a systematic literature review to highlight the main directions and trends in the use of AI in neurosurgery. METHODS: Using the PubMed search engine, 327 original journal articles published from 1996 to July 2019 and related to the use of AI technologies in neurosurgery, were selected. The typical issues addressed by using AI were identified for each area of neurosurgery. RESULTS: The typical AI applications within each of the five main areas of neurosurgery (neuro-oncology, functional, vascular, spinal neurosurgery, and traumatic brain injury) were defined. CONCLUSION: The article highlights the main areas and trends in the up-to-date AI research in neurosurgery, which might be helpful in planning new scientific projects.

[Radiation-induced meningiomas: analysis of 33 cases]. / Radioindutsirovannye meningiomy: analiz 33 nablyudenii.

BACKGROUND: Development of meningiomas correlating with irradiation has been described in the last century. Different biological features of radiation-induced meningiomas depending on dose and type of irradiation have been observed in recent years. MATERIAL AND METHODS: There were 8848 patients (women - 74.3%) with intracranial meningiomas for the period from 2000 to 2014 who underwent surgery at the Burdenko Neurosurgical Center. Radiation-induced meningiomas were identified in 33 patients (13 (38%) men and 20 (62%) women) aged 16-76 years (median 56 years). Medical data were retrospectively analyzed. Follow-up period ranged from 5 to 22 years (median 12) after verification of histological diagnosis. Meningiomas were preceded by X-ray irradiation of the scalp for ringworm (microsporia or trichophytosis) in 26 cases (79%) (group A). Group B enrolled 7 (21%) patients after previous radiotherapy for other tumors (retinoblastoma, chiasmal glioma, pituitary adenoma, basalioma). Data were compared using Mann-Whitney and Fisher's exact tests. RESULTS AND DISCUSSION: Incidence of radiation-induced meningiomas was 0.37% in our sample. Meningioma diagnosis dates after X-ray epilation (median 52 years) significantly differed from that after radiotherapy (median 22 years) (Mann-Whitney test, p=0.0003). Primary multiple meningiomas were diagnosed only in the 1st group (Fisher's exact test, p=0.0005). Recurrent meningiomas after the first surgery were more common in the first group (58%) compared to the second one (14%) (Mann-Whitney test, p=0.0003). CONCLUSIONS: The latency period is shorter after radiotherapy (median 22 years compared to 52 years after X-ray epilation). Incidence of atypical and malignant meningiomas directly correlates with irradiation dose. Approximately equal incidence of radiation-induced meningiomas after X-ray epilation in women and men can indicate other mechanisms of development of these tumors in comparison with spontaneous ones. Radiotherapy is followed by occurrence of meningiomas within the irradiated area. These tumors are usually single. In case of X-ray epilation, the tumors may be localized anywhere within the intracranial space (convexital and/or parasagittal localization in 77% of cases). Multiple neoplasms occur in 42% of cases. Refusal of head X-ray epilation for the treatment of a ringworm for the last 50 years may be followed by reduced incidence of radiation-induced meningiomas, especially multiple ones. However, extended indications for radiotherapy of various brain diseases can result an increase of the incidence of meningiomas within the irradiated area.

[Neurological semiotics of benign craniofacial tumors]. / Nevrologicheskaia semiotika dobrokachestvennykh kraniofatsial'nykh opukholei.

AIM: To identify the most frequently occurring symptoms resulting from the affection of internal and external skull base in patients with benign tumors of the anterior and middle cranial base. MATERIAL AND METHODS: The authors analyzed a complex of history, clinical, and instrumental data as well as results of combined treatment of 642 patients with benign tumors of the anterior and middle cranial base operated Medical Research between 2007 and 2011. RESULTS: Neurological signs and symptoms in patients with benign tumors of the anterior cranial base, parasellar region, and middle cranial fossa were studied. In the majority of cases, the tumor extended extracranially. The most common groups of symptoms were identified and described, the most important groups are presented in the diagrams. The proposed scheme is applicable also for malignant tumors or other mass lesions of the same localization. CONCLUSION: Effective treatment and selection of the best management of a patient depends on modern medical approaches and techniques including neuroimaging. Careful assessment of symptoms is crucial in detection of tumors in the early stage. Dynamic monitoring of the patient using the proposed scheme will contribute to early detection of tumor recurrence or progression.

[Drainage-associated meningitis in neurocritical care patients. The results of a five-year prospective study]. / Drenazh-assotsiirovannye meningity u patsientov otdeleniia neiroreanimatsii. Rezul'taty piatiletnego prospektivnogo nabliudeniia.

AIM: to determine the incidence rate and risk factors for drainage-associated meningitis in neurocritical care patients. MATERIAL AND METHODS: The prospective study included 539 patients who spent more than 48 h at the Department of Neurocritical Care and underwent external ventricular drainage. The incidence rate and risk factors for drainage-associated meningitis were evaluated. RESULTS: Over a 5-year period, 2140 patients have been hospitalized to the Department of Critical and Intensive Care (DCIC) for more than 48 h; of these, 539 patients underwent external ventricular drainage (EVD). Drainage-associated meningitis developed in 99 patients, which amounted to 19.8 (CI 16.3-23.3) per 100 patients with drainage and 18.3 (CI 14.3-22.2) per 1000 days of drainage. The incidence rate of drainage-associated meningitis did not significantly correlate with different neurosurgical diseases, but there was a tendency for meningitis to predominate in EVD patients with vascular pathology of the central nervous system (CNS). The rate of artery catheterization for direct measurement of systemic BP and the use of vasopressor agents were significantly higher in the group of patients with drainage-associated meningitis (p<0.05). ALV was used in 98 (99%) of 99 patients with drainage-associated meningitis; respiratory support was used in 325 (80.8%) patients without meningitis (p<0.01). An analysis of the ventricular drainage duration revealed a significantly (p<0.05) larger number of days of using EVD in the group of patients with drainage-associated meningitis. In most critical care patients (57.6%), meningitis developed during the first week of drainage. Cerebrospinal fluid leakage occurred significantly more frequently in patients with drainage-associated meningitis than in patients with EVD and without meningitis (p<0.01). Based on a microbiological examination, the etiology of drainage-associated meningitis was established in 57.1% of cases. The leading pathogens were coagulase-negative staphylococci (48.3%) and Acinetobacter baumannii (18.3%). CONCLUSION: The incidence rate of drainage-associated meningitis was 19.8 per 100 patients and 18.3 per 1000 days of drainage. The risk factors significantly predominating in patients with drainage-associated meningitis include the duration of drainage, association with external CSF leakage, as well as factors associated with indicators of the overall severity of the condition.

[Features of the course of nosocomial meningitis in patients of neurosurgical intensive care unit].

OBJECTIVE: To determine the incidence rate and risk factors of nosocomial meningitis in patients with complicated postoperative period. MATERIAL AND METHODS: We report the results of prospective observation of the course of bacterial meningitis in patients with complicated postoperative period at neurosurgical intensive care unit in 2010-2014. RESULTS: Nosocomial meningitis (NM) developed in 146 patients, which accounted for 12.6±1.0% (CI, 10.74-14.66). Patients with meningitis were characterized by longer stay at ICU, prolonged mechanical ventilation, need for central venous access and invasive hemodynamic monitoring, as well as longer course of antibacterial therapy. Frequency of invasive monitoring of intracranial pressure was similar in these two groups of patients. Bloodstream infections (14.8% vs. 4.9%; p<0.000), respiratory tract infections (55% vs. 35.6%; p<0.000), and urinary tract infections (56.4% vs. 30.9%; p<0.000) were more frequently observed in patients with NM. The following significant differences were observed between the group of NM patients and the control group: more frequent use of external ventricular drain (72.5% vs. 26.1%; p<0.000), number of reoperations (64.7% vs. 36.3%; p<0.000), and the total operating room time (417.3 min vs. 337.5 min; p<0.000). Etiology was ascertained in 61.0±4.0% of cases of nosocomial meningitis. CoNS (33.0%) and Acinetobacter baumannii (21.3%) were the main pathogens isolated from cerebrospinal fluid. The mortality in patients with meningitis was 31.5±3.8%. CONCLUSION: External ventricular drain, repeated surgery, long-term stay in the operating room, as well as other types of infections may be considered as risk factors for developing nosocomial meningitis in neurosurgical patients at ICU.

[Life quality of patients with benign tumors of the anterior and middle part of the skull base after surgery and during follow-up].

The results of surgical and combination therapy of 302 patients with benign tumors of the anterior and middle regions of the skull base with allowance for the functional outcomes (immediately after surgery and during the catamnestic follow-up) are reported. The Karnofsky and Rankin scales and the Anterior Skull Base Questionnaire (ASBQ) were used for the analysis. Radical tumor resection, as compared to partial resection, reduces the quality of life in the early postoperative period but increases it in future; the use of radiation therapy in combination treatment for patients with radically inoperable tumors does not worsen their quality of life in the late postoperative period.

[Videooculography in evaluation of oculomotor function in patients with mass lesions of pineal region, midbrain and pons].

Aim of this study was to assess feasibility of videooculography in evaluation of oculomotor function and its dynamics in patients with mass lesions of pineal region, midbrain and pons. Computed videooculography was performed in 48 patients with tumors of pineal region and midbrain, 9 patients with pontine hematomas and 10 healthy volunteers. 25 patients with midbrain and pineal neoplasms were followed after tumor resection or open biopsy. We evaluated amplitude of eye movements in normal and impaired oculomotor function. 4 grades decreases of amplitude upwards, downwards, medially and laterally were emphasized. In early postoperative period statistically significant decrease of amplitude in patients with clinical deterioration was observed. Application of videooculography allows reliable quantitative assessment of oculomotor function, registration and storage of examination data and follow-up of oculomotor function for observation of tendencies in course of disease.

[Papilledemas: clinical features in space-occupying lesions of the brain].

Neuroophthalmological symptoms were analyzed in 513 patients with papilledemas in space-occupying lesions of the brain. The ophthalmoscopic features of papilledemas, the pattern of visual impairments and the developmental pattern of papilledemas were considered. Several determinants of the clinical course of papilledemas, such as their stage, the grade of malignancy, and the site of a space-occupying lesion, and a patient's age, were identified. The ability to diminish visual functions generates a need for early detection of papilledemas in patients with space-occupying lesions of the brain and for timely neurosurgical treatment in order to normalize intracranial pressure.

[Confocal scanning laser retinal tomography in study of 3-D topography of the optic disk in patients with papilledema].

Confocal scanning laser tomography (CSLT) giver the opportunity to describe stereometric parameters of the optic disk in patients with different stages of papilledema. CSLT of the optic disk (Heidelberg Retina Tomograph II) was performed in 20 healthy volunteers (40 eyes) and in 85 patients with papilledema caused by cerebral tumors (8 eyes without papilledema, 52 eyes with early, 38 with moderate and 56 with severe stage of papilledema, and 9 with chronic papilledema and optic atrophy). Rim volume (RV) and disk area (DA) were measured. CSLT was performed during postoperative follow-up in 40 patients. The difference in RV (p < 0.01) and DA (p < 0.01) between normal optic disk and optic disk with early and moderate edema, and optic disk with severe edema, was significant. Stereometric parameters of optic disks measured by CSLT provide objective quantitative assessment of papilledema in patients with cerebral tumors. CSLT is especially valuable in monitoring of papilledema.

[Neuroophthalmological aspects of benign intracranial hypertension].

Benign intracranial hypertension (BICH) is characterized by elevated spinal fluid pressure in the absence of space-occupying lesion in the skull, dilated cerebral ventricles, significant neurological disorders, and altered spinal fluid composition. Forty-nine patients with a female predominance were examined. Their age ranged from 4 to 52 years (median 39 years). The most common predictors of BICH were overweight, endocrine disorders, and cerebral sinus thrombosis. Ophthalmoscopically, the patients were found to have early, moderate, and significant papilledema, and secondary optic atrophy. Examination of visual functions revealed these or those disturbances of visual acuity and/or field of vision in 43 of the 49 patients. The incidence and degree of visual disturbances depended on the stage of papilledema. Timely diagnosis and treatment in patients with BICH allows the development of visual disturbances to be prevented in them.

[Congestive optic disks in the brain massive lesions].

To study the specific features of development of papilledema (PE) in brain space-occupying lesions, the authors made a statistical analysis of neuroophthalmologic symptoms in 962 patients with brain tumors, colloid cysts of the third ventricle and cholesteatomas, who had been examined at the Research Institute of Neurosurgery during a calendar year. PE was identified in 30.8% of the patients. The frequency of PE was ascertained to depend on histological pattern, space-occupying lesion site, and age. Visual disturbances in PE were observed in more than a third of patients and manifested themselves as both diminished visual acuity and defects in the field of vision. The frequency and degree of visual deficit depended on the stage of PE.

[Ultrasound study of optic nerves in intracranial hypertension].

Ultrasonography was used to measure the standing of the optic disk (OD) and the diameter of the orbital segment of the optic nerve together with its tunics in a control group of the examinees, in patients with different stages of optic disk disease (ODD) and with clinical signs of intracranial hypertension in the absence of the ophthalmoscopic pattern of ODD. Eleven healthy volunteers and 168 patients with intracranial hypertension induced by brain tumors, hydrocephalus, and benign intracranial hypertension were examined. Ultrasonography revealed that there was a great difference in the standing of OD into the vitreous body in different stages of ODD, as evidenced by their comparison with that in the control group (healthy individuals), and a significant increase in the diameter of the optic nerve subtunicary space in patients with intracranial hypertension as compared with the controls. Intracranial hypertension regression as demonstrated by ultrasonography leads to a concurrent reduction in the previously increased diameter of the optic nerve subtunicary space and the standing of OD into the vitreous body.

[A role of laser retinal tomography in the study of patients with congestive optical disks].

A Heidelberg retina tomograph II was used to examine 35 (55 eyes) patients with intracranial hypertension caused by brain tumors. Ophthalmoscopy revealed no changes in the optic disk in 6 eyes, mild, moderate, and severe congestive optic disks (COD) in 6, 14, and 29 eyes, respectively. The volume of the neuroretinal rim (V) and the area of the Optic disk (S) were measured. There was a significant difference in V (p < 0.01) and S (p < or = 0.02) with the intact optic disk, in mild, moderate, and severe COD. One-week-to-one-month follow-ups after tumor removal showed that in 12 patients the positive or negative changes, as evidenced by the readings of a retina tomograph, corresponded to those in the ophthalmoscopic pattern. Laser retinal tomography is an objective and accurate study of the stereometric parameters of COD in patients with intracranial hypertension, which permits a follow-up of COD.

Electronic patient record for N.N. Burdenko Neurosurgical Institute: on the verge of implementation.

This presentation is the first report about development of Electronic Patient Record System (EPRS) for N.N. Burdenko Neurosurgical Institute (NSI). This EPR system is the core of Integrated Automatic Information System intended to support all business processes running in the Institute. A new technology for developing information systems in poorly formalized subject domains, named IBS/Records, was was created.

Professional knowledge as the basis of electronic patient record systems.

The presentation is devoted to the role of professional knowledge in the developing of Electronic Patient Record System (EPRS). The main example--EPRS for N.N. Burdenko Neurosurgical Institute (NSI).