Background. Degenerative stenosis of the spinal canal is a condition observed mostly in the elderly. It significantly decreases their quality of life and physical activity. Surgical treatment of the patients is frequently associated with significant surgical and anesthesiologic risks especially during conventional open decompression. The problem of decreasing invasiveness of surgical interventions is important for these patients because in their case lighter postoperative injury and decreased recovery duration after surgery are crucial.

   Aim. To evaluate clinical outcomes in patients with central degenerative lumbosacral stenoses after percutaneous endoscopic decompression.

   Materials and methods. Comparison of clinical and radiological characteristics before surgery, on day 1 and month 6 after surgery was performed. Among clinical characteristics, pain syndrome in the leg / legs per the Visual Analogue Scale (VAS) and Oswestry Disability Index (ODI) were evaluated. The evaluated radiological characteristic was the spinal canal cross-sectional area (CSA) in cm2 per the magnetic resonance imaging. Statistical analysis was performed using the SPSS Statistics v. 26.0 (IBM, USA) software.

   Results. Pain syndrome in the leg / legs (decreased VAS score) after surgery decreased significantly (р = 0.006). No significant difference between the VAS scores on day 1 and 6 months after the surgery was found (adjusted significance level padj = 1.000). Similarly, disability index changes were statistically significant after surgery (р = 0.005): ODI score decreased. Additionally, no statistically significant differences between ODI score on day 1 and 6 months after surgery were observed (padj = 1.000). Increase in CSA of the spinal canal was statistically significant (р = 0.001), no differences in this parameter on day 1 and 6 months after surgery were found. Conversion to microsurgical access was necessary in 4 (23.5 %) of 17 patients. No statistically significant differences in VAS, ODI scores and CSA changes at different time points were observed in patients who required conversion.

   Conclusion. Results of the study show significant improvement of the patients’ clinical status (per the VAS and ODI) and achievement of adequate radiological decompression (increased spinal canal CSA) which persisted for 6 months after percutaneous endoscopic interventions.

   Introduction. Intracranial arteriovenous malformations (AVM) are considered one of the life-threatening pathologies which are challenging to manage. Endovascular embolization of intracranial AVMs is a line of management which developed over the past two decades to downgrade the lesion, a step is thought to make surgeries of more favorable outcome.

   Patients and methods. All patients who were diagnosed with brain AVM in Mansoura University Hospitals between January 2017 through December 2022 were retrospectively analyzed. Clinical and radiological outcome were studied, as well as surgeons’ satisfaction and procedural difficulties.

   Results. Nine patients met the criteria for multimodal management, seven of them were female, mean age of the group 36 years. Patients’ mRS remained unchanged after embolization sessions, one patient had an added neurological deficit in the form of increased severity of motor deficit after surgery, which was reversible during follow up period, mean follow up period is 103 days.

   Conclusion. Pre-operative embolization is a safe tool to be added to the muti-modal treatment of high grades cerebral AVM’s with good outcome and feasible surgical technique.

   Background. Resection of deep-seated space-occupying brain lesions is traditionally associated with a triad of problems: retraction injury, limited radicality, and risks of augmentation of neurologic symptoms. Port-assisted or tubular surgery has been recently gaining popularity as its goal is to minimize these risks. Therefore, it is necessary to evaluate its effectiveness and compare it to the traditional interventions.

   Aim. To perform comparative analysis of the immediate outcomes of traditional and port-assisted surgery of deep-seated space-occupying brain lesions.

   Materials and methods. The results of resection of deep-seated space-occupying brain lesions in 61 patients (31 men and 30 women) including 36 patients with diffuse glial tumors and 25 patients with nodular lesions were retrospectively analyzed. Among them, 35 patients were operated on using the traditional technique with spatulas (1^st group), 26 patients – using tubular retractors, port-assistance (2^nd group). Evaluation and comparison of radicality and neurologic outcomes in these patient groups, as well as differentiation of possible factors of unfavorable outcomes were performed.

   Results. Radicality of glial tumor resection per the total / subtotal / partial grading in the 1^st group was 0, 50 and 50 %; in the 2^nd group, 21.4; 35.7 and 42.9 %. Total resection of nodular lesions in the 1^st group was achieved in 76.9 % of cases; in the 2^nd group, in 91.7 %. Clinical deterioration was observed in 13 (37.1 %) patients of the 1^st group and 4 (15.4 %) patients of the 2^nd group, but it was mostly transient. Compared to traditional surgery, the use of tubular retractors allowed to achieve significantly smaller trephination size (13.2 ± 4.6 cm² versus 22.7 ± 7.8 cm²) and decrease postoperative in-hospital period (3 [3; 5] days versus 12 [6; 16] days).

   Conclusion. The use of port-assistance in surgery of deep-seated space-occupying brain lesions is preferential to traditional surgery in terms of higher radicality for similar size and histology of lesions and lower rate of neurologic complications without imposition of additional constraints.

   Background. Over time as a result of improved surgical techniques, the emergence of new minimally invasive methods of intracerebral hematoma evacuation and more careful selection of patients potential for surgery, surgical treatment of hypertensive intracerebral hematoma has taken its niche in modern neurosurgery.

   Aim. To study the results of surgical treatment of patients with hypertensive intracerebral hematomas in the Republic of Tatarstan.

   Materials and methods. The retrospective multi-center study included data from 1127 patients with hypertensive intracerebral hemorrhages from 4 regional and 14 primary vascular centers in the Republic of Tatarstan for 2022, 87 patients were operated.

   Results. Among surgical methods the share of the open method was 64,4 %, endoscopic 32,2 %, external ventricular drainage / ventriculoperitoneal shunt implantation 3,4 %. Hospital mortality was 25,3 %. The highest mortality and incidence of recurrent hemorrhages were in patients operated on within the first 8 hours from the onset of symptoms. When comparing comparable groups (in terms of hematoma volume and severity of patients with intracerebral hemorrhage), in the surgical group hospital mortality was 2,9 times lower (22,6 %) than in the conservative group (65,6 %).

   Conclusion. Surgical removal of aggressive hypertensive intracerebral hematoma, at a patient’s severity of 8 points and above on the Glasgow coma helps reduce mortality. Endoscopic removal should be more widely used for deep aggressive haematomas. The optimal time to remove aggressive hypertensive intracerebral hematoma is 8 to 24 hours from the onset of a stroke.

   Hypertrophic olivary degeneration is a rare form of transsynaptic neuronal degeneration caused by damage to the dentato-rubro-olivary pathway also known as the Guillain–Mollaret triangle. In magnetic resonance diagnostics, this is manifested by increasing the size and hyperintensity of the inferior olivary nucleus in T2-weighted images. The article presents two clinical cases of hypertrophic olivary degeneration, which was caused by cavernous angiomas with hemorrhage in the brainstem. Knowledge about this pathological change in the olivary nuclei of the medulla oblongata and a correct diagnosis help to avoid wrong diagnostic and their consequences.

   Background. The term “aggressive pituitary adenoma” arose as a result of transforming the term “atypical pituitary adenoma”, which was used in WHO classification for pituitary adenomas with specifications of higher labeling index Ki-67 (≥3 %) and increased number of mitoses with expression of the p53 proteins. However, not all tumors with these features were aggressive, and currently, according to the European Society of Endocrinology Clinical Practice Guideline for the management of aggressive pituitary tumors and carcinomas (2018), aggressive pituitary tumors are labeled as tumors that have invasive and unusually rapid or clinically significant growth which occurs despite the use of standard treatment protocols (pharmacological, surgical and radiation). Till date, there are numerous papers in literature describing various schemes and indications for the use of temozolomide. The efficiency of ongoing therapy, according to different authors, varies from 29 to 81 %, with an average effectiveness ranging between 40–45 %.

   Aim. To present our own experience of using temozolomide in the treatment of patients with aggressive pituitary tumors.

   Materials and methods. Three patients were included in the study, one male (45 years old) and 2 females (61 and 29 years old). All three patients included in the study first underwent surgical resection followed by radiation therapy if no response / hormonal activity didn’t resume. The decision to start temozolomide protocol was held by concerned medical commission under supervision of local ethical committee.

   Results. All patients responded well to temozolomide therapy with decrease in the size of tumor and decrease in levels of prolactin in cases of prolactinoma.

   Conclusion. The most important step in treating patients with aggressive pituitary adenomas is their early diagnosis, which could be possible only if the specific identifying markers of aggressiveness were found, which unfortunately are not found yet.

   One of the complications of latent intracranial hypotension is a dystopia of the tonsils of the cerebellum, which can lead to an erroneous diagnosis of “Chiari malformation type 1”.

   The aim of the work is to pay attention to the symptoms, course and diagnosis of acquired (pseudomalformation) Chiari in intracranial hypotension syndrome.

   The work is based on clinical and neurological data and magnetic resonance imaging of the brain and spinal cord of a woman aged 28 years, obtained during dynamic observation over a number of years. At the acute onset of the disease with severe postural headache, minimal neurological symptoms, magnetic resonance imaging revealed a dynamic dystopia of the cerebellar tonsils from the plane of the large occipital foramen 15 mm below it and stable hydromyelia in the thoracic region, which inclined to the diagnosis of Chiari malformation type 1. However, flattening of the bridge, thickening of the dura mater, the tendency to rounding of the sagittal sinus, narrowing of subarachnoid spaces, basal cisterns, prolapse of the bottom of the 3^rd ventricle into the prebridge cistern indicated the possibility of intracranial hypotension caused by latent liquorrhea, which was confirmed by magnetic resonance imaging with intravenous administration of gadolinium containing contrast agent in the mode of a strongly weighted T2-three-dimensional image with inversion and weakening of fluid – revealed hidden liquorrhea at the cervical level. A diagnosis of Chiari pseudomalformation has been established, which excludes surgical intervention – decompression of the posterior cranial pit. When diagnosing Chiari malformation type 1 and detecting cerebellar tonsillar dystopia, it is always necessary to exclude Chiari pseudomalformation associated with other primary pathology, in particular, with latent cerebrospinal liquor, the consequence of which is intracranial hypotension, which has specific signs in magnetic resonance imaging, and requires a different therapeutic tactic.

   Combination of pituitary adenomas with meningiomas or vestibular schwannomas is a rare occurrence: in scientific literature, only individual cases or small case series are described. The article presents a rare clinical observation of a female patient who underwent surgery and radiotherapy due to hormonally inactive pituitary adenoma and neurofibromatosis type 2 (intracranial meningioma and neurinoma (schwannoma)) found during a follow-up exam. A combination of histologically different intracranial tumors (pituitary adenoma, meningioma, and neurinoma) is extremely rare and requires corresponding approaches to treatment.

   Intraorbital arteriovenous fistulas are rare arteriovenous shunts inside the orbit without connection with the cavernous sinus. This article describes a clinical case of multiple metachronous intraorbital arteriovenous shunts in a patient with univentricular heart disease and secondary erythrocytosis. Transarterial embolization of the first shunt had a positive clinical effect for 2 months. The recurrence of symptoms was caused by the formation of a new shunt on the same draining vein, but in a place remote from the previous locus. Repeated embolization gave a positive effect for the same period. The next relapse had a more malignant course, up to dislocation of the eyeball. The right orbit decompression has given a stable positive clinical effect up to the present moment. Based on extremely limited literature data of such cases and our own experience, we concluded that an individual and multidisciplinary approach to such patients with careful postoperative follow-up is necessary.

   The aim of the work – to present a case of radiation-induced complication after radiosurgical stereotaxic treatment of cavernous malformation of the brain.

   A patient, 34-year-old, applied to the Radiosurgery Center of the N. V. Sklifosovsky Research Institute for Emergency Medicine with complaints of frequent headaches, general weakness. The magnetic resonance imaging of the brain revealed a deep cavernous malformation in the left hemisphere of the brain. In order to reduce the risk of re-rupture of the cavernous malformation, it is recommended to perform a stereotaxic radiosurgical operation using the Elekta Leksell Gamma Knife Perfexion apparatus. The possibilities of treating cerebral cavernous malformations have significantly expanded with the use of stereotaxic radiosurgery. Radiosurgery is an alternative treatment for symptomatic cavernous malformations in cases of deep-seated lesions in functionally significant areas of the brain, the surgical removal of which is associated with a high risk of worsening neurological symptoms. However, complications after radiosurgical stereotaxic treatment are an urgent problem, and subsequent follow-up with a clinical assessment of the patientʼs condition and neuroimaging requires attention and a multidisciplinary approach.

   Background. Large vestibular schwannomas can not only change the anatomy and structure of the facial nerve in the process of growth, but also encapsulate it over a considerable length. Despite the development of modern neurosurgical techniques and achievements in the field of microscopy, it is often impossible to avoid damage to its integrity during the separation of the facial nerve, which is associated with the development of paresis of the facial muscles in the postoperative period. The use of intraoperative neurophysiological monitoring in surgery for vestibular schwannomas pursues the following tasks: identification of neural structures, timely detection of signs of their damage, and prevention of iatrogenic neurological deficit.

   Aim. To analyze the results of microsurgical removal of vestibular schwannomas using intraoperative neurophysiological monitoring.

   Materials and methods. A series of clinical cases of patients who underwent microsurgical removal of sporadic vestibular schwannomas using suboccipital retrosigmoid transmeatal access under the control of multimodal intraoperative neurophysiological monitoring is presented. Neurological assessment of the facial nerve function was carried out in the early postoperative period and 3 months after surgical treatment using the House–Brackmann scale.

   Results. Postoperative results of surgical treatment were collected in 11 patients. According to the results of the neurological assessment in the early postoperative period, the result was regarded as successful in 5 cases, satisfactory in 3 cases, and poor in 3 cases (grade V on the House–Brackmann scale). The use of direct monopolar stimulation technique made it possible to identify the location and course of the facial nerve with high accuracy in all patients. In 2 cases, the tumor was resected subtotally due to the appearance of neurophysiological predictors of facial nerve dysfunction.

   Conclusion. The use of multimodal neurophysiological monitoring when removing large vestibular schwannomas can make surgical treatment more controllable and thus indirectly affect functional outcomes.

   Patients with carotid artery stenosis have high risk of ischemic stroke. Carotid endarterectomy is the method of choice for ischemic stroke prevention in patients with symptomatic and asymptomatic carotid artery stenosis. Such stages of carotid endarterectomy as selection, artery clamping, and placement of a temporary intraluminal shunt can be accompanied by ischemic complications due to embolism and insufficient collateral blood flow. Multimodal intraoperative neurophysiological monitoring consisting of cerebral oximetry, somatosensory and motor evoked potentials monitoring,
electroencephalography, and transcranial Doppler ultrasound allows to perform direct and indirect monitoring of cerebral perfusion during the whole surgery and can be used for prediction of surgical outcomes. Multimodal approach to intraoperative neurophysiological monitoring is the most sensitive and specific approach for predicting and minimizing postoperative neurologic deficit.

   Some trauma patients develop peripheral nerve injury due to crush injuries resulting from severe trauma and blunt force. Recovery from peripheral nerve injuries is frequently inadequate and requires months or even years. This recovery process is associated with both the innate immune system, comprised of Schwann cells, neutrophils, and macrophages and the adaptive immune system. Prior to the regeneration process, the two immune systems work collaboratively to eliminate myelin and axon protein debris in Wallerian degeneration.

   The article considers a popular question in the modern world: can artificial intelligence replace a qualified specialist? The author presents their thoughts on this problem based on the current state of computer technologies.