[Olfactory (subfrontal) schwannoma: case report and literature review]. / Ol'faktornaya (subfrontal'naya) shvannoma: klinicheskii sluchai i obzor literatury.

BACKGROUND: Olfactory nerve schwannomas are extremely rare. Their origin is still unclear, since olfactory nerve has no Schwann cells. There are about 70 case reports of olfactory nerve schwannoma in the world literature. Original articles devoted to this issue are currently absent. RESULTS: We present a 55-year-old patient with olfactory nerve schwannoma who underwent surgery at the Federal Center of Neurosurgery in Novosibirsk. MRI revealed extracerebral mass lesion of anterior cranial fossa base with left-sided lateralization resembling meningioma of the olfactory fossa. The patient underwent microsurgical resection of mass lesion of anterior cranial fossa base through left-sided lateral supraorbital craniotomy. The tumor macroscopically resembled schwannoma. Total resection was carried out. Considering morphological structure and immunomorphological characteristics, we verified schwannoma Grade 1. CONCLUSION: Olfactory nerve schwannomas are rare tumors with benign histological structure. Relapses after total resection are unlikely. However, further research of this rare pathology and long-term postoperative follow-up are required.

[The new algorithm for stratification of the risk of venous thromboembolic events in elective neurosurgery and its prognostic significance]. / Novyi algoritm stratifikatsii riska venoznykh tromboembolicheskikh oslozhnenii v planovoi neirokhirurgii i ego prognosticheskaya znachimost'.

Early identification of risk groups is essential for effective and target prevention of venous thromboembolic events (VTE) in all areas of surgery. For this purpose, the authors has developed and put into practice an algorithm distinguishing the groups of low, moderate and high risk of VTE among neurosurgical patients. OBJECTIVE: To assess predictive value of the developed algorithm for elective neurosurgical interventions. MATERIAL AND METHODS: The study included 7914 patients who underwent surgery between January 2018 and December 2019. According to the algorithm, we identified the groups of low (1536 (19%) patients), moderate (4554 (58%) patients) and high risk (1824 (23%) patients). Moreover, patients were divided into subgroups depending on surgical procedure. We analyzed the incidence of VTE and mortality in all groups. RESULTS. INCIDENCE: Of VTE with a 95% confidence interval in the low-risk group was 0.65% [0.26; 1.04], in the moderate risk group - 1.82% [1.47; 2.24], in the high-risk group - 12.61% [11.02; 14.09]. When comparing various surgical interventions, we revealed more common VTE after vascular microsurgery (15.62%), in patients with brain tumors (12.63%) and spinal cord tumors (6.52%). CONCLUSION: The risk stratification algorithm has demonstrated its convenience and significant predictive value for determining the risk of VTE among elective neurosurgical patients. In addition, different incidence of VTE was demonstrated in patients with various neurosurgical diseases.

[Incidence and risk factors of venous thromboembolic events after resection of various brain tumors]. / Chastota i faktory riska razvitiya venoznykh tromboembolicheskikh oslozhnenii u patsientov posle udaleniya razlichnykh vidov opukholei golovnogo mozga.

Venous thromboembolic events (VTE) can significantly complicate postoperative period in neurosurgical patients. It is known that patients with brain tumors are especially susceptible to VTE. OBJECTIVE: To determine the incidence and risk factors of VTE in patients with various brain tumors. MATERIAL AND METHODS: All patients with brain tumors underwent surgery in 2019 (n=610). They were divided into the groups depending on tumor type: sellar region, intracerebral, extracerebral neoplasms and metastases. All patients underwent screening and prevention of VTE in accordance with the protocol accepted in the hospital. We analyzed the incidence of VTE in each group and significance of various risk factors. RESULTS: Overall incidence of VTE was 14.9% (91 cases). Deep vein thrombosis (DVT) was the most common - 85 cases (93.4%). Less common events were DVT combined with pulmonary embolism (PE) (n=5, 5.5%) and PE alone (n=1; 1.1%). PE caused death in 2 cases (0.3%). In patients with sellar tumors, incidence was 21.7% [13.4%; 29.35%], among intracerebral tumors - 13.8% [9.04%; 18.62%], extracerebral neoplasms - 15.4% [11.02%; 19.69%], metastases - 7.9% [1.32%; 11.84%]. Univariate and multivariate analysis revealed some risk factors of VTEs such as gender, age, surgery time, length of ICU-stay over 12 hours, body mass index >30 kg/m2. Moreover, risk factors have different significance in patients with different types of tumors. CONCLUSION: In this study, we found a high incidence of VTE among patients with brain tumors. Incidence and risk factors of VTE depend on the type of tumor.

[Invasive EEG for temporal lobe epilepsy: selection of technique]. / Invazivnyi video-EEG monitoring pri visochnoi epilepsii: vybor metoda.

BACKGROUND: Non-invasive EEG reveals epileptogenic zone in 70% of patients. In other cases, invasive EEG monitoring is indicated. Various implantation strategies and techniques of intracranial EEG (icEEG) potentially provide different outcomes. Choosing the optimal icEEG technique may be challenging. OBJECTIVE: To analyze the results of icEEG in adults with temporal lobe epilepsy and to determine the algorithm for selection of optimal invasive EEG technique. MATERIAL AND METHODS: The study included 82 patients with temporal lobe epilepsy who underwent invasive EEG. Effectiveness of invasive EEG was determined by detection of epileptogenic zone and post-resection outcomes. Postoperative results were analyzed throughout more than 6-month follow-up period using the Engel grading system. Statistical analysis was conducted using the Fisher's exact test. RESULTS: Epileptogenic zone was revealed in 72 (88%) cases. Invasive EEG was supplemented by another modality in 3 (4%) patients. Mean follow-up period after resection was 17 months in 45 patients. Favorable outcomes were achieved in 31 (69%) cases. Statistical analysis showed that identification of epileptogenic zone depends existing of lesion and symptoms of seizures. Selection algorithm for optimal technique of invasive EEG was determined considering own results and literature data. CONCLUSION: Invasive EEG results and post-resection outcomes demonstrated favorable efficacy of original algorithm. The last one may be used in decision-making on optimal technique of invasive EEG in adults with temporal lobe epilepsy.

[Intracranial meningiomas in children]. / Vnutricherepnye meningiomy detskogo vozrasta.

Meningiomas are rare in children and distinguished from the tumors in adults by clinical and biological aspects. Moreover, some histological forms and localizations are even casuistic in adults. There were 178 patients younger 18 years old with brain tumors. All patients underwent surgery at the pediatric department for 5-year period. Meningiomas were diagnosed in 5 cases that accounted for 2.8% of the total number of brain tumors in children. The authors reported children with intracranial meningiomas and discussed certain features of the course of disease in these patients.

[Stereotactic radiosurgery in treatment of trigeminal neuralgia]. / Stereotaksicheskaia radiokhirurgiia v lechenii trigeminal'noi nevralgii.

It was not until relatively recently that the method of stereotactic radiosurgery has started to be used for treating trigeminal neuralgia. Being minimally invasive, this method can be considered an attractive alternative to invasive surgical methods. OBJECTIVE: The objective of this study was to analyze the results of treatment in patients with trigeminal neuralgia using the Leksell Gamma Knife system. MATERIAL AND METHODS: The results of stereotactic radiosurgery were analyzed in 52 patients (31 females and 21 males aged 31 to 79 years) who had undergone treatment at the Radiosurgical Center of MIBS (St. Petersburg) in 2009-2016. Forty-four patients were diagnosed with typical trigeminal neuralgia; four patients, with atypical neuralgia; and four patients, with symptomatic neuralgia (accompanying multiple sclerosis). Pain severity was assessed using the Visual Analogue Scale (VAS) and the Barrow Neurological Institute Scale (BNIPS) before and after the surgery, as well as during the follow-up period (mean duration, 3 years). RESULTS: Pain was reduced in 38 (86.4%) patients with type 1 neuralgia. The effect usually was not observed immediately after the surgery but was delayed from several weeks to 12 months (median, 2 months; interquartile range) [1, 4]. The surgery was ineffective in 6 (14%) patients. Eight (18%) patients had a relapse on average after 2 years and 5 months. By the end of the follow-up period, score I according to the BNIPS was achieved in 22 (50%) patients; score II or III was achieved in 7 (16%) patients. Primary reduction of pain was achieved in two patients with type 2 neuralgia; one of them had a relapse after 19 months. Among patients with symptomatic neuralgia, the primary effect was achieved in three patients, but two of them later had a relapse. CONCLUSION: Stereotactic radiosurgery can be used to alleviate pain in most patients with type 1 trigeminal neuralgia, but its results are inferior to those of invasive interventions. According to our findings, 18% of patients had a relapse. For patients with multiple sclerosis accompanied by type 2 and symptomatic trigeminal neuralgia, this method is not sufficiently effective. When both microvascular decompression and stereotactic radiosurgery can be used to treat for type 1 and 2 trigeminal neuralgia, patient's choice is crucial. It is important to inform the patient both about the potential complications of the interventions and about the delayed effect of the surgery and relapse frequency.

[The use of an opect optic system in neurosurgical practice]. / Opyt ispol'zovaniia opticheskoi sistemy orest v praktike neirokhirurga.

INTRODUCTION: Modern neurosurgical practice is impossible without access to various information sources. The use of MRI and MSCT data during surgery is an integral part of the neurosurgeon's daily practice. Devices capable of managing an image viewer system without direct contact with equipment simplify working in the operating room. AIM AND OBJECTIVES: To test operation of a non-contact MRI and MSCT image viewer system in the operating room and to evaluate the system effectiveness. MATERIAL AND METHODS: An Opect non-contact image management system developed at the Tokyo Women's Medical University was installed in one of the operating rooms of the Novosibirsk Federal Center of Neurosurgery in 2014. In 2015, the Opect system was used by operating surgeons in 73 surgeries performed in the same operating room. The system effectiveness was analyzed based on a survey of surgeons. RESULTS: The non-contact image viewer system occurred to be easy-to-learn for the personnel to operate this system, easy-to-manage it, and easy-to-present visual information during surgery. CONCLUSIONS: Application of the Opect system simplifies work with neuroimaging data during surgery. The surgeon can independently view series of relevant MRI and MSCT scans without any assistance.

[Motor cortex stimulation in deafferentation facial pain]. / Stimuliatsiia motornoi kory pri deafferentatsionnoi litsevoi boli.

OBJECTIVE: To demonstrate the results of treatment of poorly controlled deafferentation facial pain using motor cortex stimulation and to review the relevant literature. MATERIAL AND METHODS: The study included 8 patients (3 males and 5 females) with deafferentation facial pain who were implanted with a system of constant motor cortex stimulation at the Illinois University in Chicago in 2004-2016 and Novosibirsk Federal Center of Neurosurgery in 2017. The patients' age ranged from 37 to 81 years (mean age, 57.5 years). Scale-based assessment of the pain severity was performed at admission to hospital, at discharge, and during follow-up. The visual analogue pain scale, Barrow Neurological Institute pain scale (BNIPS), and McLaughlin scale were used. RESULTS: Immediately after surgery, a significant improvement in the form of pain reduction by 80-100% occurred in 4 patients. The pain intensity at discharge from the hospital decreased by 55%, on average. During the follow-up period, the efficacy of motor cortex stimulation was assessed (McLaughlin scale) as very good by 3 of the 8 patients, as good by 4 patients, and as unsatisfactory by 1 patient. CONCLUSION: Our findings and recent studies have demonstrated that motor cortex stimulation is one of the treatment options for deafferentation facial pain. Even a slight decrease in the intensity of excruciating and debilitating pain (assessed by patients as a good effect) gives grounds for application of the procedure. Further research is needed to define more precise criteria for selecting patients for this treatment and to increase the efficacy of stimulation.

[Penetrating orbitocranial injury: a review of the literature and a case report of injury by a watercolor brush in a 3-year-old child]. / Pronikaiushchaia orbitokranial'naia travma: obzor literatury s opisaniem klinicheskogo sluchaia raneniia akvarel'noĭ kistochkoĭ u rebenka 3 let.

We present a rare case of orbitocranial penetrating injury by a watercolor brush in a 3-year-old child. Injuries of this localization can affect important orbital structures (eyeball, blood vessels, nerves, muscles) and cause severe intracranial damages. In some cases, diagnosis of these injuries in children may be difficult due to the lack of marked clinical manifestations. The presented clinical case illustrates the approaches for choosing methods for diagnosis of injury in childhood and subsequent treatment options.

[Early postoperative results of surgical treatment of patients with anterior clinoidal meningiomas]. / Rannie rezul'taty khirurgicheskogo lecheniya patsientov s meningiomami perednego naklonennogo otrostka.

Resection of anterior clinoidal meningiomas is a challenging task due to their localization, frequent involvement of the major cerebral arteries and cranial nerves, a high risk of postoperative neurological deficits, and low radicalness of surgery. AIM: To evaluate the radicalness of microsurgical removal and a neurological deficit in the early postoperative period in patients with anterior clinoidal meningiomas. MATERIAL AND METHODS: A total of 35 patients with anterior clinoidal meningiomas underwent surgery at the Department of Neurooncology of the Novosibirsk Federal Neurosurgical Center in the period from 2013 to July 2016. There were 29 (82.9%) females and 6 (17.1%) males. The mean patient age was 50.1 years (31-72 years). According to the Al-Mefty classification (1990), type 1 tumors occurred in 10 (28.6%) patients, type 2 tumors were in 22 (62.8%) patients, and type 3 tumors were in 3 (8.6%) patients. Twenty four (68.6%) patients had large (greater than 4.0 cm) tumors, 7 (20.0%) patients had medium (2.0-4.0 cm) tumors, and 4 (11.4%) patients had small (less than 2.0 cm) meningiomas. The tumor involved the major arteries in 21 (60.0%) patients. RESULTS: The lateral supraorbital approach was used in 26 (74.3%) patients, and the pterional approach was used in 9 (25.7%) cases. The tumor was resected totally (Simpson II) in 25 (71.4%) cases and subtotally (Simpson IV, subtype A and B) in 10 (28.6%) patients. In the early postoperative period, cerebral symptoms regressed in 20 (57.1%) patients; visual acuity improved in 2 of 13 (15.4%) patients. Four (11.4%) patients developed IIIrd nerve palsy; 2 (5.7%) patients developed severe hemiparesis. The mortality rate was 2.9%. CONCLUSION: The completeness of resection directly depends on the tumor consistency: soft meningiomas can be totally resected (Simpson II) with a good functional outcome. In the case of solid tumors, total resection may lead to serious ischemic disorders with a high risk of death.

[Spinal cord stimulation in the treatment of chronic pain syndromes].

AIM: The study objective was to estimate the efficacy of chronic epidural spinal cord stimulation in the treatment of patients with neuropathic pain syndrome. MATERIAL AND METHODS: A system for chronic spinal cord stimulation (St. Jude) was implanted to 75 patients with neuropathic pain syndrome. Fifty three (70.7%) patients were diagnosed with failed back surgery syndrome (FBSS); 9 (12.0%) patients had complex regional pain syndrome type II; 4 (5.3%) patients had diabetic polyneuropathy of the lower limbs; 3 (4.0%) patients had idiopathic pelvic-perineal pain; 2 (2.7%) patients had spinal stroke pain; 2 (2.7%) patients had postherpetic intercostal neuralgia; 1 (1.3%) patient had stump pain; 1 (1.3%) patient had spinal cord injury pain. The treatment efficacy was evaluated using the visual analog scale (VAS) and DN4 questionnaire. The follow-up period ranged from 6 to 18 months. RESULTS: 136 patients underwent test stimulation at the Center in 2014. A significant reduction in pain was observed in 75 (55.1%) patients. These patients underwent the second stage of surgery that included implantation of permanent electrodes and a generator. The mean VAS score was 6.5 (maximum: 10; minimum: 5) before surgery, 3.2 at discharge, and 3.1 after 3 and 6 months. The VAS score amounted to 3.6 after 12 months. Complications in the form of pain at the generator implantation site and the need for removal of the system occurred in 2 patients (2.6%), electrode migration was observed in 4 (5.3%) cases. CONCLUSION: Chronic epidural spinal cord stimulation is an effective and safe technique for the treatment of drug-resistant chronic neurogenic pain syndromes.

[Teflon granuloma after microvascular decompression of the trigeminal nerve root in a patient with recurrent trigeminal neuralgia].

The use of a Teflon implant for Jannetta surgery in patients with trigeminal neuralgia is complicated in rare cases by the development of a Teflon granuloma and can cause recurrent facial pain. The article presents a clinical case of a Teflon granuloma developed after microvascular decompression of the trigeminal nerve root, describes the surgical findings and histological picture, and analyzes the literature, causes of granuloma development, and recommendations for treatment of these patients.

[The use of frameless navigation during endoscopic interventions in children with multilocular hydrocephalus].

INTRODUCTION: The use of the endoscopic technique largely improves treatment outcomes in patients with multilocular hydrocephalus. However, impaired anatomy and the lack of usual landmarks often cause problems in planning and intraoperative identification of changed structures. The use of frameless navigation during endoscopic interventions can significantly facilitate surgeon tasks and increases the efficacy of surgery. During surgery, the neuronavigation system visualizes a rigid endoscope that interconnects separated ventricles and cysts. Surgery can be completed with guiding a stent through an operating channel of the endoscope and implanting a shunt system. MATERIAL AND METHODS: Ten children underwent 11 endoscopic interventions using frameless intraoperative navigation at our clinic in 2013-2014. The number of surgically interconnected compartments ranged from 3 to 5. Simultaneous placement of a shunt system was performed in 8 of 11 interventions. RESULTS: Clinical improvement as a result of the operation was achieved in all children. 2 patients underwent re-operations 5 months and 1 year after endoscopic intervention. CONCLUSION: Thus, the use of frameless navigation during endoscopic interventions makes their implementation most efficient and safe for the patient.

[A change in the sagittal balance in elderly and senile patients with degenerative stenosis of the lumbar spine].

Degenerative-dystrophic changes in the spine have general nature, which leads to changes in the balance parameters and consequently, other elements of the musculoskeletal systems. This article is devoted to analysis of the literature data, based on which we conclude that changes in the sagittal balance in elderly and senile patients as the restabilization stage still remain unexpected.

Generation of two iPSC lines, (ICGi015-A and ICGi015-B), by reprogramming peripheral blood mononuclear cells from a patient with Parkinson's disease.

Studying Parkinson's disease (PD), one of the most common neurodegenerative disorders worldwide, requires different model systems, including patient-specific induced pluripotent stem cell lines. With the help of non-integrating episomal vectors the iPSC lines ICGi015-A and ICGi015-B were generated from blood mononuclear cells of PD patient, carrying three SNPs, associated with PD development. The obtained iPSC lines express pluripotency markers and demonstrate the ability to in vitro differentiate into the three germ layers. These cell lines may be useful for studying molecular mechanisms of PD and for drug screening.

[Experience of the use of gasserian ganglion balloon compression in patients with trigeminal neuralgia associated with multiple sclerosis]. / Opyt ballonnoi mikrokompressii gasserova uzla v lechenii trigeminal'noi nevralgii patsientov s rasseiannym sklerozom.

AIM: To evaluate the efficacy of gasserian ganglion balloon compression in patients with trigeminal neuralgia associated with multiple sclerosis (MS). MATERIAL AND METHODS: Eight patients (3 men, 5 women), aged from 46 to 66 years (mean age 55 years), with trigeminal neuralgia associated with MS underwent surgery. An average duration of the pain syndrome was 8,4 years. Six patients had previous surgeries due to facial pain. Percutaneous balloon compression of gasserian ganglion was performed to all patients. Follow up period was from 2 to 24 months. RESULTS: Six patients (75%) reported 100% of pain relief right after the surgery, 2 patients (25%) reported a significant decrease of pain (2-3 points on VAS). Pain recurrence occurred in 3 patients: in 4 months, in 12 months and in 6 months. All of them were operated repeatedly. After the surgery, hypoesthesia on the side of surgery was observed in all patients with a trend towards regression. There was no keratopathy or any complications. CONCLUSION: Percutaneous balloon compression of gasserian ganglion is an effective and minimally invasive method which can be performed repeatedly in patients with trigeminal neuralgia associated with MS.