Endoscopic endonasal surgery (EES) offers a direct ventral corridor to the skull base, potentially enabling maximal resection of extensive cholesteatomas (epidermoid cysts) in the posterior cranial fossa and parasellar region. However, outcomes and complications specific to this approach require detailed analysis. A retrospective review was conducted on 34 patients who underwent EES for cholesteatomas of the posterior fossa and parasellar region at a single center from 2011 to 2025 year. Extent of resection (near-total > 95

Background: Endoscopic endonasal surgery (EES) offers a direct ventral corridor to the skull base, potentially enabling maximal resection of extensive cholesteatomas (epidermoid cysts) in the posterior cranial fossa and parasellar region. However, outcomes and complications specific to this approach require detailed analysis. Methods: A retrospective review was conducted on 34 patients who underwent EES for cholesteatomas of the posterior fossa and parasellar region at a single high-volume center (2011-2025). Surgical approaches were tailored to the lesion's extent. Extent of resection (near-total >95%, subtotal 90-95%), complications, and neurological outcomes were analyzed. Results: Near-total resection was achieved in 65% of cases and subtotal in 35%. The most frequent complications were postoperative cerebrospinal fluid (CSF) leakage (23.5%) and meningitis (23.5%; 33.3% in patients with intradural extension). Rates were significantly higher than for other skull base tumors. Only visual symptoms showed consistent postoperative improvement. New or worsened cranial nerve deficits occurred in 12% of cases. The rates of CSF leakage and meningitis were 25% and 33%, respectively. Arrested hydrocephalus requiring shunting developed in 14.7% of patients. Conclusion: EES provides a valid alternative for the surgical management of posterior fossa and parasellar cholesteatomas, allowing for a high degree of resection. However, it is associated with a notably higher risk of CSF leakage and meningitis compared to EES for other pathologies, attributable to the lesion's adhesive and inflammatory characteristics. Furthermore, significant recovery of preoperative neurological deficits (except visual) is uncommon. These findings underscore that such complex procedures should be performed in specialized centers with extensive expertise in endoscopic skull base surgery and multidisciplinary perioperative care.

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.

Craniopharyngioma (CP) is a benign epithelial tumor predominantly localized in chiasmatic-sellar region and third ventricle. There are two histological variants of CP: adamantinoma-like (ACP, 85%) and papillomatous (PCP). These types differ significantly in origin and histological structure. PCP predominantly occurs in adults. Treatment of CP, including effectiveness of radiotherapy, is described in multiple studies and mainly devoted to pediatric patients. OBJECTIVE:To clarify disease-free survival in adults with newly diagnosed CP depending on resection quality; to evaluate the effectiveness of stereotactic irradiation and treatment depending on histological characteristics of tumor. MATERIAL AND METHODS:We analyzed treatment outcomes in 398 adults over 10-year follow-up. Stereotactic irradiation was performed in 11.6% of patients. The follow-up data were obtained in 68.1% of patients. We compared 5-year disease-free survival rates after different resections with and without subsequent irradiation. RESULTS:Total resection is effective and provides significantly lower risk of CP recurrence. Effectiveness of stereotactic irradiation after incomplete resection was also confirmed. CONCLUSION:Total resection of ACP and PCP provides high disease-free survival rates. Stereotactic irradiation after incomplete resection is followed by similar outcomes. PCPs are characterized by less aggressive growth and do not recur after total resection.

Introduction The tumors of the diencephalon region (thalamic-hypothalamic-pituitary system) include a large group: pituitary adenomas, craniopharyngiomas, gliomas, and others. Tumors differ in the histological structure, and manifestations of the clinical symptoms; by hormonal data; by approaches and methods in treatment. Psychic symptoms are revealed in disease in addition to cerebral, neuroendocrine symptoms, neurological disorders. Psychoorganic syndrome is represented by emotional, motivational, personal, cognitive impairments, inversion of the sleep-wake cycle, seizures. Disorders of mental activity are detected in all tumors of this localization in varying degrees, according to the different authors from 20 to 100%; affective pathology varies from 2 to 80% by the literature. Objectives To study the emotional disorders in the structure of psychoorganic pathology in tumors of diencephalon region Methods 290 patients (18-78 years old, mean age 38+2): pituitary adenomas (PA), as the most common – 170 (58,6%), craniopharyngiomas (CG), as with the most varied manifestation of mental symptoms – 120 (41,4%). Methods: psychopathological, data from endocrinological, neurological, neuroimaging methods. Results Emotional disorders were detected in patients from 30 to 68% of cases, depending on the histology of the tumours: PA with excessive secretion of growth hormone - emotional disorders are in 60%; PA with excessive secretion of adrenocorticotropic hormone - in 50%; PA with excessive secretion of prolactin - in 30%; with excessive secretion of thyroid-stimulating hormone - in 40%; non-functioning PA - in 16%; CG - in 68%. Emotional disorders were more often represented by changeable mood, depression, apathy, sleep disturbance, and visceral symptoms. Symptoms differed depending on the histology of the tumor (type and level of hormones), the volume of the lesion and direction of growth, and concomitant hypertensive-hydrocephalic symptoms. Emotional disturbances often include memory impairment, personality and behavior changes. Conclusions Emotional disorders are detected in patients in 30-68% of cases in the structure of psychoorganic pathology with damage to the diencephalon region (in particular, with pituitary adenomas and craniopharyngiomas); are determined by the topography of the tumor and histology with the involvement of the corresponding structures and nuclei in the pathological process. Disclosure of Interest None Declared

The article presents an original method for personalized predicting surgical outcomes in patients with tumors of diencephalic and suprasellar localization based on a clinical and epidemiological approach and the use of intelligent analysis (Data Mining) of clinical and electroencephalo-graphic data. Use of the methods allowed us to programmatically select nosologically specific test for making surgical outcome prognosis, including sensitivity and specificity calculations.

Dysembryoplastic neuroepithelial tumor (DNET) is a benign mixed neuronal-glial neoplasm (WHO grade 1). DNET is most often localized in temporal lobes and found in children and young people with epilepsy. There a few cases of DNET in ventricular system with dissemination along the ependyma in the world literature. MATERIAL AND METHODS:We present a rare case of T1- and T2-negative ventricular system tumor. Only FIESTA imaging revealed dissemination with multiple focal lesions of the third ventricle, its bottom and lateral walls, anterior horns of lateral ventricles, cerebellar vermis, cervical and lumbar spinal cord. RESULTS:The patient underwent transcortical endoscopic biopsy of the third ventricle tumor with simultaneous ventriculoperitoneal shunting. DNET was diagnosed, and radiotherapy was subsequently performed. Literature data on this issue were analyzed. CONCLUSION:To date, disseminated forms of DNET are extremely rare. X-ray features and morphological results allow us to establish the correct diagnosis and determine further treatment strategy.

Encephalocele or craniocerebral hernia is a disease in which there is a prolapse of the meninges and structures of the brain through a skull defect. Clinically, they are manifested by a violation of nasal breathing, deformation of the naso‑ethmoid region, and nasal liquorrhea. Various inflammatory complications (meningitis, meningoencephalitis, ventriculitis, brain abscess) can occur against the background of persistent hernia, while mortality is 8–10 %.Basal encephalocele is a rare pathology that requires an integrated approach in a specialized hospital using high‑tech equipment. Therapeutic tactics and risks are determined individually based on the patient’s age, current symptoms, size of the nasal cavity, location and size of the skull base defect. In the absence of nasal liquorrhea, it is possible to delay surgical treatment in order to be able to use an autologous bone of the calvarium, to collect a larger periosteal flap, to perform the operation using a combined approach and to minimize surgical complications. With endonasal endoscopic access, it is necessary to separate the encephalocele from the surrounding tissues, completely remove the hernial sac and visualize the bone edges of the defect, and then perform its plastic closure.Despite the fact that in most cases the existing methods of treatment are very effective, in a number of cases it is not possible to achieve the desired result. This article presents two rare clinical cases in which patients with basal encephalocele required reoperation for herniation and skull base defect repair.

Craniopharyngiomas (CP) are benign chiasmatic-sellar tumors in children and adults. Surgical resection is currently the main method for CP and largely depends on topographic and anatomical location of tumor. OBJECTIVE:To analyze topographic and anatomical classifications of CP available in the world literature. MATERIAL AND METHODS:Searching for literature data on classifications of CPs was performed in the PubMed, eLibrary and CyberLeninka databases between 1960 and 2023. We used the following keywords: «craniopharyngioma», «third ventricle», «endoscopic transnasal surgery for craniopharyngiomas». RESULTS:We found 21 eligible manuscripts. The vast majority of studies are devoted to topographic and anatomical location of CPs in their own series: baseline growth along hypothalamic-pituitary axis (4 classifications), relation to the third ventricle (5 classifications), pituitary stalk (2 classifications), optic nerves (2 classifications) and meninges (3 classifications), classification of papillomatous CPs (1 report) and adamantinomatous CPs (1 report), functional classifications of hypothalamic lesions (3 reports). CONCLUSION:Topographic classifications of CPs characterize their relation to the most important basal brain structures: pituitary gland, hypothalamus, optic pathways and circle of Willis. There are also single topographic and anatomical classifications with emphasis on morphological component of CP. Exact anatomical and topographic variant of CP is often of decisive importance for choosing the optimal surgical approach, possibility and expediency of total resection. Further clarification of relationship of CP to diencephalic structures is associated with improvement of diagnostic methods, in particular, high-resolution MRI (7.0 T) and MR tractography.

Супраселлярные краниофарингиомы (КФ) характеризуются высокой частотой поражения структур третьего желудочка, результатом чего становится нарушение регуляции энергетического гомеостаза с развитием гипоталамического ожирения (ГО). Лептин является одним из ключевых регуляторов массы тела посредством взаимодействия с нейронами гипоталамуса. В норме повышение уровня лептина ассо- циировано с усилением метаболизма и снижением массы тела. В настоящее время отсутствуют единые диагностические критерии ГО и эффективные методы терапии. Оценка повреждения гипоталамуса до и по- сле операции необходима для выбора хирургической тактики и возможности раннего терапевтического вмешательства, сдерживающего увеличение веса. ЦЕЛЬ: изучить секрецию лептина, динамику массы тела и их взаимосвязи с топографическим вариантом КФ до и после оперативного лечения. МАТЕРИАЛЫ И МЕТОДЫ: прооперировано 58 пациентов (28 мужчин и 30 женщин) медиана возраста 39 (29-54) с верифицированным диагнозом КФ. Степень вовлечения гипоталамуса оценена на основа- нии предоперационной МРТ и интраоперационных данных. Критерием ГО принято увеличение массы тела на 10 кг и более за период 6 мес. Оценка массы тела, уровня лептина крови проводилась до и через 1, 3, 6, 12 месяцев после операции. По локализации опухоли были разделены на 2 группы: 1 – стебельные КФ (24), 2- стебельно-вентрикулярные КФ (34). РЕЗУЛЬТАТЫ: 1. Стебельные КФ, замещают стебель гипофиза, достигая дна 3 желудочка. До операции ГО не выявлено ни в одном случае, медиана лептина – 5,0 нг/мл (2,8-8,1). Тотальное удаление выполнено в 79% (19), из них в 12 случаях опухоль прирастала к дну 3 желудочка. После операции ГО - 30% случаев (7), меди- ана прибавки веса - 20 кг (10-32), медиана лептина через 1 мес – 19,8 нг/мл (9,2-23.0), через 3 мес. - 17,8 (13,3-36), через 6 мес. -17,7 ( 3,0-28,7), через 12 мес. – 11,9 (3,2-22) . 2. Стебельно-вентрикулярные КФ, замещают стебель и дно 3 желудочка с распространением в его полость. До операции: ГO в 20% (7) случаев, медиана прибавки веса 16 кг (10-20). Медиана лептина 7,9 нг/мл (4,8-13,4). Тотальное удаление -в 61% случаев (21). После операции: ГО - 38%(13), медиана прибавки веса - 17 кг (11-26), из них только 2 пациента имели ГО до операции. Медиана лептина через 1 мес. – 31,0 нг/мл (18-43,6), через 3 мес. -20,6 (10,4-37,2), через 6 мес. -13,9 (8,0-21,7), через 12 мес. -12,8 (9,9-29,0). В обоих группах прибавка веса после операции наблюдалась в течение первых 6 мес. Статистически значимых различий уровня лептина до и после операции в данных группах не обнару- жено. ВЫВОДЫ: прибавка массы тела на 10 и более кг в течение 6 месяцев до операции наблюдалась только среди пациентов со стебельно-вентрикулярными КФ, что в совокупности с данными МРТ может расцени- ваться как признак гипоталамического повреждения опухолью и использоваться в качестве критерия ГО. Группу риска развития ГО составляют пациенты с опухолью с вовлечением гипоталамуса, у которых не на- блюдалось увеличение веса до операции. Нарастание массы тела после операции происходит на фоне высокого уровня лептина, что свидетельствует о лептинорезистентности вследствие структурных нару- шений диэнцефальной области.

Searchable abstracts of presentations at key conferences in endocrinology ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Background. The problem of concomitant pituitary adenomas and intracranial aneurysms is extensively covered in literature. According to various authors, the prevalence of such a combination of lesions is as high as 9 %, most commonly involving hormone‑producing pituitary adenomas and aneurysms of the anterior circulation, up to 69 % of which originate from the carotid artery. Aim. To analyze and demonstrate the treatment of patients with developed internal carotid artery aneurysm (ICA) against the background of successful conservative therapy of prolactinoma. Materials and methods. In this article we review the literature and present two clinical cases of patients with development of internal carotid artery (ICA) aneurysms after successful conservative treatment of prolactinomas. Results. In both of the described cases, ICA aneurysms with intrasellar extension developed after successful conservative treatment of large invasive prolactinomas. In both cases ICA occlusion were performed and in one of them extra‑intracranial bypass surgery was performed as well. Conclusion. The presented clinical cases suggest potential direct destructive effect of tumor tissue on vessel walls. Currently, it seems reasonable to carry out computed tomography angiography in all patients with adenomas invading the cavernous sinus.

Nasal CSF leakage is the most common complication after transsphenoidal surgery, especially in case of extended transsphenoidal access. It is one of the main and obvious risk factors of meningitis. Introduction of effective reconstructive techniques made it possible to reduce the incidence of postoperative CSF leakage. Fibrin glue is one of the main components in transsphenoidal surgery for skull base defect closure. The use of autologous fibrin glue excludes immune response due to its biocompatibility. Modern technologies of preparation of autologous fibrin glue make it possible to obtain a large volume of glue that ensures complete sealing of skull base defect. At the same time, autologous glue contains factors promoting rapid tissue regeneration. It is of great importance for engraftment of autologous transplants in the area of skull base defect.

Searchable abstracts of presentations at key conferences in endocrinology ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Basal meningoencephalocele is a rare pathology that occurs due to the prolapse of meninges and brain tissues through a bone defect in the skull base. Treatment of patients with this pathology consists in the removal of the meningoencephalocele, followed by plasty of the skull base defect. One of the ways to close defects of the skull base is to use vascularized flaps. Vascularized flaps are the method of choice of plastic material in adults, however, in pediatric practice, there is insufficient data on the effectiveness and safety of their use. Purpose: to assess the effectiveness and safety of the use of vascularized flaps in the removal of meningoencephalocele, as well as to clarify the indications for their use in pediatric practice Material and methods. A retrospective analysis of a series of patients with basal meningoencephalocele aged 0 to 18 years, operated from 2008 to 2020. Comparison of two groups, divided according to the types of methods used for plastics of skull base defects, has been carried out. Results. There was a statistically significant difference in the groups for the localization of defects (p = 0.048), complaints in the postoperative period for pain in the wound on the left hip (p < 0.001). There was no statistically significant difference in the groups in terms of the size of the defect (p = 1), the frequency of using lumbar drainage (p = 0.141), the duration of surgery (p = 0.2), and blood loss (p = 0.248). Conclusions. Vascularized flaps are effective for plasty of the skull base defect in children in the removal of meningoencephalocele. The safety of using flaps intraoperatively and in the early postoperative period has been proved. The question of the long-term results and the influence of the formation of a vascularized flap on the structures of the facial skeleton remains unstudied. When planning the elimination of meningoencephalocele in children and the choice of plastic material, it is necessary to take into account the localization of the fistula.

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.