[Modern concepts of genetic and immunohistochemical features of prolactin-secreting pituitary adenomas].

Prolactinomas are the most common secreting adenomas of the pituitary. In 20% of cases resistance to dopamine-agonists treatment is observed. Medical therapy resistance causes progression of pathological symptoms of hyperprolactinemia and negative topographic and anatomical changes of prolactinoma. The causes of ineffectiveness of dopamine agonists therapy are not fully understood as well as approaches to managing patients require clarification. Current concepts of resistance are based on the data obtained as a result of surgery or after a period of long-term ineffective therapy. Thus, it is very important to find methods of assessing the sensitivity of prolactin-secreting adenomas to drug therapy before surgical treatment. Genetic and immunohistochemical studies find special place among these methods, making it possible to predict adenoma's response to drug therapy at early diagnostic stage. Obtained results will allow us to form personalized algorithm for managing patients.

[Application of autologous fibrin glue for skull base defect closure in transsphenoidal surgery. Case report and literature review]. / Primenenie autologichnogo fibrinovogo kleya dlya plastiki defekta osnovaniya cherepa v transsfenoidal'noi khirurgii. Opisanie klinicheskogo sluchaya i obzor literatury.

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.

[Central diabetes insipidus after resection of sellar-suprasellar tumors: prevalence and predictors of manifestation]. / Tsentral'nyi nesakharnyi diabet posle udaleniya opukholei khiazmal'no-sellyarnoi oblasti: rasprostranennost' i prediktory manifestatsii.

Central diabetes insipidus is a neuroendocrine disorder caused by disturbances in antidiuretic hormone release. The last one is responsible for fluid and electrolyte balance regulation. The most common cause of diabetes insipidus is resection of sellar-suprasellar tumors followed by damage to hypothalamic nuclei responsible for antidiuretic hormone release, disruption of antidiuretic hormone transportation from hypothalamus or its release by neurohypophysis. According to various data, postoperative diabetes insipidus occurs in 13-30% of cases. The highest risk of diabetes insipidus is observed after resection of craniopharyngioma, Rathke's cleft cyst and ACTH-releasing pituitary microadenoma. This review is devoted to prevalence and predictors of diabetes insipidus after resection of sellar-suprasellar tumors.

[Combination of pituitary adenomas and intracranial aneurysms]. / Sochetanie adenom gipofiza i intrakranial'nykh anevrizm.

The combination of intracranial tumors and asymptomatic brain aneurysms is an urgent problem, since it can significantly affect surgical intervention. Aneurysms are common in patients with meningioma, glioma and pituitary adenoma. According to certain authors, combination of aneurysms with pituitary adenomas is 7 times more common than with other tumors. In these cases, a comprehensive examination of the patient and decision-making on surgical strategy are required. This review is devoted to epidemiology, diagnosis and treatment of patients with a combination of pituitary adenomas and intracranial aneurysms detected intraoperatively or at the preoperative stage. The manuscript is illustrated by cases observed at the Burdenko Neurosurgery Center.

[Transcranial microsurgical decompression of the optic canal in surgical treatment of meningiomas of the sellar region]. / Transkranial'naya mikrokhirurgicheskaya dekompressiya kanala zritel'nogo nerva v khirurgii meningiom khiazmal'no-sellyarnoi oblasti.

RATIONALE: When removing the meningiomas of the sellar region, there is always a risk of visual impairment for various reasons, in particular, as a result of traction damage to the optic nerve. Decompression of the optic canal increases nerve mobility during tumor manipulation. In cases of meningioma growing into the canal, its decompression often seems necessary. AIM: Evaluation of the effectiveness and risks of performing decompression of the optic canal. MATERIALS AND METHODS: The study included patients with meningiomas of the parasellar location, who underwent surgical treatment at the Burdenko Neurosurgical Center for the period from 2001 to 2017. They were divided into two groups - main and control. The main group consisted of 129 patients who underwent decompression of the optic nerve canals when the tumor was removed. The tumor matrix in this group was most often located in the region of the tuberum sellae, supradiaphragmally, in the region of the anterior clinoid process and the optic canal. In 31 cases, decompression was bilateral - during one operation and using one access in 27 patients; in 4 cases, the decompression of the second canal was delayed for 1.5-3 months after the first operation. 160 decompressions were performed by the intradural and 7 - by extradural methods. During intradural decompression, the roof of the optic canal was resected, and during extradural decompression, the lateral wall of the canal was trephined. The control group consisted of 308 patients who did not undergo canal decompression when the tumor was removed. It included meningiomas with a predominant location of the matrix in the area of the tuberclum and diaphragm of the sella. Tumors in both groups were removed according to the same principles (matrix coagulation, mainly the gradual removal of the tumor, the use of ultrasonic aspirator, a situational decision on the radicality of the operation, etc.). The main difference between operations in these two groups was only canal related algorithms (with or without its trepanation), as well as the probable prevalence of significant lateral tumor growth in cases with canal trepanation. Visual functions in the «primary¼ group were evaluated before and after operations with trepanation of the canal depending on various factors - the initial state of vision and the radicality of the tumor excision, including removal from the canal. The differences in the postoperative dynamics of vision in the main and control groups were studied. The primary data processing was carried out using the program MSExcel. Secondary statistical processing was carried out using the program Statistica. To assess the statistical significance of differences in the results obtained in the compared patient groups, the Chi-square test was used, and in the case of small groups - the exact Fisher test was applied. RESULTS: In the main group postoperative vision improvement of varying degrees on the side of trepanation was registered in 36.9% (59 out of 160) cases, no vision changes were found in 36.9% (59 out of 160), and in 26,2% (42 out of 160) the eyesight deteriorated. If preserving vision is attributed to a satisfactory result, then in general the results of these operations should be considered good. A comparative study of the results of removal of meningiomas with trepanation of the canals (main group) or without it (control group) was carried out among patients with the most critical vision situation (visual acuity 0.1 and below, up to only light perception). These groups are comparable in the number of observations - 62 and 73 respectively. The predominance of cases with improved vision in the main group compared with the control group (50.0% versus 38.36%) and a lower incidence of vision impairment (22.58% versus 34.25%) were found. However, the revealed differences are statistically unreliable and make it possible for us to talk only about the trend. The complications associated with trepanation of the canal include mechanical damage to the nerve by the drill. In our series of observations, there was only 1 case of abrasion of the nerve surface with the burr, which did not lead to a significant visual impairment. With the intradural method of trepanation in the area of the medial wall of the canal, the sphenoid sinus may open (in our series, in 34 cases out of 160 trepanations). Immediately closure of these defects was performed by various auto- and allomaterials in various combinations (pericranium, fascia, muscle fragment, hemostatic materials, and fibrin-thrombin glue). A true complication - CSF rhinorrhea liquorrhea developed in only one case, which required transnasal plastic surgery of the CSF fistula using a mucoperiostal flap. CONCLUSIONS: 1. Trepanation of the optic canal in cases of meningiomas of parasellar localization is a relatively safe procedure in the hands of a trained neurosurgeon and does not worsen the results of operations compared with the excision of the same tumors without trepanation of the canal. 2. The literature data and the results of our study make it possible to consider the decompression of the optic canal as an optional, but in many cases, useful option that facilitates the transcranial removal of some meningiomas of the sellar region.

[Primary sellar neuroblastoma (clinical case and literature review)]. / Pervichnaya sellyarnaya neiroblastoma. Klinicheskoe nablyudenie i obzor literatury.

Neuroblastoma is a malignancy developing from the embryonic neuroblasts of sympathetic nervous system. Primary sellar neuroblastomas are extremely rare (there are currently only 11 case reports in the literature). Possible development of neuroblastoma in sellar region expands differential diagnosis of local processes due to inclusion of neuroblastoma into the spectrum of suspected tumors. We report a literature review and description of a patient with primary sellar neuroblastoma.

[Transsphenoid extirpation of pituitary adenomas in patients with McCune-Albright syndrome (two cases from practice and literature review)]. / Transsfenoidal'noe udalenie adenom gipofiza u patsientov s sindromom MakK'iuna-Olbraita (dva sluchaia iz praktiki i obzor literatury).

INTRODUCTION: McCune-Albright Syndrome is a rare genetic disease characterized by the formation of fibrous osteodysplasia foci of various localization, including the bones of skull base. Having a gross lesion of the main bone body and the simultaneous formation of the pituitary adenoma, its transnasal removal becomes very difficult. MATERIAL AND METHODS: Two clinical observations are presented where at patients with the classic manifestation of McCune-Albright syndrome we were able to successfully remove somatotropinomas with endoextrasellar growth. In both cases the presence of visual disorder was the indication for surgery. RESULTS: Despite pronounced deviations in the anatomy of the skull base bones in both cases we managed to access the Turkish saddle. Removal of the pituitary tumor did not differ from standard surgery. Improved vision after surgery was observed in two patients. Tumors were removed subtotally and clinical and biochemical remission of acromegaly was not achieved. In both cases, the tumors had morphological signs of atypia. Patients continued to receive therapy with somatostatin analogues and radiation. CONCLUSION: The possibility of performing transnasal surgery in this category of patients using specific instruments and intraoperative navigation is shown.

[Biopsy and resection of skull base tumors using transorbital endoscopic approaches: primary results]. / Biopsiia i udalenie novoobrazovanii osnovaniia cherepa s primeneniem transorbital'nykh éndoskopicheskikh dostupov: pervye rezul'taty.

AIM: Transorbital neuroendoscopic surgery is a new skull base surgery technique that uses the orbit as an artificial corridor to the anterior and middle skull base. The space is created between the periorbita and orbital walls by their additional resection and gentle traction of the orbital contents. Skull base structures are reached using cosmetic incisions. The major advantages of transorbital endoscopic approaches include their variety, possibility of their combination, and access to the central and lateral skull base lesions. The aim of this study was to analyze the primary results of transorbital endoscopic biopsy and resection of skull base lesions, which were performed at the N.N. Burdenko National Medical Research Center for Neurosurgery (Moscow, Russia). MATERIAL AND METHODS: In 2017-2018, the authors operated on 12 patients with skull base lesions using transorbital endoscopic approaches. The series included ten female and two male patients. The patient's age varied between 24 and 78 years. All patients were admitted for the first time. Half of them underwent biopsy, while the other half underwent tumor resection. The upper-lateral transorbital approach with an eyebrow incision was used in most (8/12) patients; the retrocaruncular approach was used in two cases; the lateral retrocanthal approach was applied in one case; the upper-medial approach with an eyebrow incision was used in one patient. RESULTS: The histological diagnosis was established in all six biopsies: 3 pseudotumors, 2 WHO Grade I meningiomas, and 1 clear-cell kidney cancer. Tumor resection was successful in 5 out of 6 patients; repeated surgery was required in one patient. In one case, the transorbital approach was combined with the transnasal one for treatment of supraorbital mucocele. One patient developed a persistent neurological deficit (dysfunction of the fifth and sixth nerves) after upper-lateral transorbital surgery. There were no poor cosmetic results in the series. CONCLUSION: Transorbital neuroendoscopic surgery needs an interdisciplinary approach and a sufficient amount of surgical experience. Surgical skills setting includes microsurgical and endoscopic tumor resection, harvesting and positioning of free and vascularized grafts for skull base reconstruction and prevention of postoperative enophthalmos, and facial incisions and their cosmetic closure. Implementation of new local vascularized flaps may significantly improve the results of transorbital endoscopic procedures and extend the spectrum of indications.

[Oculomotor nerve neurinomas. Case reports and a literature review]. / Nevrinomy glazodvigatel'nogo nerva. Opisanie klinicheskikh sluchaev i obzor literatury.

Oculomotor nerve neurinoma not associated with neurofibromatosis type II is an extremely rare pathology. According to the topography, cisternal, cisternocavernous, cavernous, orbitocavernous, and orbital tumor groups are distinguished. The clinical picture of the disease is characterized mainly by either oculomotor disorders or pyramidal symptoms, depending on the tumor localization. Neurinomas of the oculomotor nerve rarely occur without oculomotor disorders. However, in some patients with these tumors, the third nerve function remains intact. In this paper, we present clinical cases of two patients with oculomotor nerve neurinomas and analyze the relevant literature.

[Transsphenoidal surgery of suprasellar meningiomas - is there a future for the technique?] / Transsfenoidal'naia khirurgiia supraselliarnykh meningiom - est' li budushchee u metodiki?

Surgery of suprasellar meningiomas is a challenge and associated with a high risk of injury to the vascular-neural structures lying along the approach and surrounding the tumor. Currently, many foreign clinics and our Center have introduced a technique for resection of suprasellar meningiomas through the anterior extended transsphenoidal endoscopic endonasal approach. OBJECTIVE: The study objective was to evaluate the role of extended transsphenoidal endoscopic endonasal approaches in surgery of suprasellar meningiomas. MATERIAL AND METHODS: The present study is a retrospective analysis of surgical treatment outcomes in 45 patients (11 males and 34 females aged 23 to 70 years (median, 50 years) with suprasellar meningiomas who underwent surgery for skull base tumors using the anterior extended transsphenoidal endoscopic endonasal approach in the Surgery Department of the Burdenko Neurosurgical Institute in the period from 2009 to 2017. In all cases, surgery was the primary method of treatment. RESULTS: Total tumor resection (the tumor was resected completely together with an infiltrated DM - Simpson 1) was achieved in 77.8% (35/45) of cases; subtotal resection (more than 80% of the tumor was removed) was in 17.8% (8/45) of cases; in 4.4% (2/45) of cases, resection was partial (less than 80% of the tumor was resected). Worsening or development of visual impairments immediately after surgery occurred in 13 (28%) of 45 patients. In 3 of them, vision was completely recovered on conservative treatment by the time of hospital discharge. In 4 patients, vision partially improved by the time of discharge. In 6 patients, vision was not recovered by discharge (in 2 of them, vision partially improved during follow-up). Therefore, by the time of hospital discharge, deterioration in vision occurred in 10 (22%) of 45 patients. In 7 (21.2%) out of 33 patients who had visual impairments before surgery, there was an improvement in vision in the postoperative period. CONCLUSION: Analyzing the findings and generalizing our experience, we may say that, in surgery of suprasellar meningiomas, the anterior extended transsphenoidal endoscopic endonasal approach should be used for relatively small (up to 3 cm), medially located symmetrical tumors that do not involve large vessels. The efficacy of this technique for tumors extending into the optic nerve canals requires additional analysis in a larger series of cases.

[Lateral extended transsphenoidal endoscopic approach through the pterygopalatine fossa in surgery for meningoencephalocele of the lateral sphenoid recess]. / Lateral'nyi rasshirennyi transsfenoidal'nyi éndoskopicheskii dostup cherez krylovidno-nebnuiu iamku v khirurgii meningoéntsefalotsele bokovogo karmana klinovidnoi kosti.

Meningoencephalocele is a hernial protrusion of the medulla and meninges through a defect in the skull bones. Due to poor accessibility of meningoencephalocele located in the lateral sphenoid recess region, modern surgical treatment of this pathology prefers to use endoscopic transsphenoidal approaches. MATERIAL AND METHODS: The study included 4 patients with meningoencephalocele of the lateral recess of the sphenoid sinus (1 male and 3 females; mean age, 46.8 years). All patients underwent resection of meningoencephalocele and repair of a skull base defect using the lateral extended transsphenoidal endoscopic approach through the pterygopalatine fossa (transpterygoid approach). RESULTS: In all patients, meningoencephalocele was resected to the bone defect level. There was no postoperative liquorrhea. Complications included bacterial meningitis (1 case), asymptomatic imbibition of the temporal lobe pole (1 case), and temporary numbness in the V2 innervation area of the trigeminal nerve (1 case). CONCLUSION: The paper describes and demonstrates advantages of the lateral extended transsphenoidal endoscopic approach through the pterygopalatine fossa (transpterygoid approach) for surgical treatment of patients with meningoencephalocele of the lateral sphenoid recess.

[Preoperative and postoperative endocrine disorders associated with pituitary stalk injuries caused by suprasellar growing tumors]. / Éndokrinnye rasstroistva do i posle operatsii pri razlichnykh porazheniiakh steblia gipofiza supraselliarno rastushchimi opukholiami.

The pituitary stalk (PS) is a relatively thin bundle connecting the hypophyseal stalk to the pituitary gland; it consists of both axons of the hypothalamic nuclei (terminating in the neurohypophysis) and the system of portal vessels. Compression of the PS by a space-occupying lesion or its transection (forced or intended) during surgery may lead to the development of endocrine disorders: hypopituitarism, diabetes insipidus, and hyperprolactinemia. The modern literature lacks studies evaluating the severity of endocrine disorders depending on the PS condition before and after surgery. PURPOSE: The study purpose was to investigate endocrine disorders in patients with sellar region (SR) tumors and the PS that was compressed before surgery and preserved or transected during a neurosurgical intervention. MATERIAL AND METHODS: The study included 139 patients with various SR tumors. In 82 patients, a preoperatively compressed PS was preserved (41 patients with hormonal inactive adenoma (HIA) and 41 patients with suprasellar meningioma); in 57 patients, the PS was transected during surgery (46 patients with pituitary stalk craniopharyngioma and 11 patients with hormonally inactive endosuprasellar pituitary adenoma). The hormonal status (PRL, TSH, LH, FSH, fT4, cortisol, testosterone, or estradiol) was examined in all patients both before and after surgery. RESULTS: Hyperprolactinemia was preoperatively detected in 37% of patients with tumors compressing the PS. Elimination of PS compression (tumor resection) led to normalization of the PRL level in most patients and was not accompanied by aggravation of hypopituitarism symptoms. Transection of the PS caused panhypopituitarism in 100% of patients and diabetes insipidus in 93% of cases. After transection of the PS, hyperprolactinemia did not develop in 59% of patients with craniopharyngiomas (CPs) and 82% of patients with HIA. CONCLUSIONS: Given the difference in symptoms associated with compression and surgical transection of the PS, we believe that these two concepts should be clearly distinguished. The PS compression syndrome includes primarily hyperprolactinemia (37% of cases); elimination of PS compression leads to normalization of the PRL level in most patients and is not accompanied by aggravation of hypopituitarism symptoms. The PS transection syndrome in patients with CP and HIA led to the development of panhypopituitarism in all patients and permanent diabetes insipidus in most of them. The causes of the absence of hyperprolactinemia in many patients with PS transection require further research. The surgeon planning intraoperative PS transection to increase the radicality of surgery should be well informed about the consequences of this procedure for the patient's endocrine status.

[The use of platelet gel for repair of a cerebrospinal fluid fistula of the skull base (a case report and literature review)]. / Primenenie trombotsitarnogo gelia dlia plastiki likvornoi fistuly osnovaniia cherepa (sluchai iz praktiki i obzor literatury).

Nasal liquorrhea is a serious problem in surgery of skull base tumors, which is associated with a high risk of purulent-septic complications. This paper presents a case of successful repair of a cerebrospinal fluid fistula with an autologous platelet gel in the postoperative period after removal of meningioma of the anterior cranial fossa base, which was accompanied by a purulent-inflammatory complication in the surgical wound area.

[Application of intraoperative electromagnetic frameless navigation in transcranial and endoscopic neurosurgical interventions]. / Primenenie bezramnoi sistemy intraoperatsionnoi élektromagnitnoi navigatsii pri transkranial'nykh i éndoskopicheskikh neirokhirurgicheskikh vmeshatel'stvakh.

The paper summarizes the experience in using a system of electromagnetic intraoperative frameless navigation in various neurosurgical pathologies of the brain. The electromagnetic navigation technique was used for 102 operations in 98 patients, including 36 transnasal endoscopic interventions. There were no intraoprtative and postoperative complications associated with the use of the system. In the process of using the system, factors influencing the accuracy of navigation and requiring additional control by the surgeon were identified. PURPOSE: The study purpose was to evaluate the use of electromagnetic navigation in surgical treatment of patients with various brain lesions. MATERIAL AND METHODS: The system of electromagnetic navigation was used for 102 operations in 98 patients (42 males and 56 females, including 18 children; median age, 34.8 years (min, 2.2 years; max, 69 years)) in the period from December 2012 to December 2016. In 36 patients, the system was used for endoscopic interventions. In 19 patients, electromagnetic navigation was used in combination with neurophysiological monitoring. RESULTS: In our series of cases, the frameless electromagnetic navigation system was used in 66 transcranial operations. The mean error of navigation was 1.9±0.5 mm. In 5 cases, we used the data of preoperative functional MRI (fMRI) and tractography for navigation. At the same time, in all 7 operations with simultaneous direct stimulation of the cortex, there was interference and significant high-frequency noise, which distorted the electrophysiological data. A navigation error of more than 3 mm was associated with the use of neuroimaging data with an increment of more than 3 mm, image artifacts from the head locks, high rate of patient registration, inconsequence of touching points on the patient's head, and unsatisfactory fixation to the skin or subsequent displacement of a non-invasive localizer of the patient. In none of the cases, there was a significant effect of standard metal surgical tools (clamps, tweezers, aspirators) located near the patient's head on the navigation system. In two cases, the use of massive retractors located near the patient's localizer caused noise in the localizer and navigation errors of more than 10 mm due to significant distortions of the electromagnetic field. Thirty-six transnasal endoscopic interventions were performed using the electromagnetic frameless navigation system. The mean navigation error was 2.5±0.8 mm. CONCLUSION: In general, electromagnetic navigation is an accurate, safe, and effective technique that can be used in surgical treatment of patients with various brain lesions. The mean navigation error in our series of cases was 1.9±0.5 mm for transcranial surgery and 2.5±0.8 mm for endoscopic surgery. Electromagnetic navigation can be used for different, both transcranial and endoscopic, neurosurgical interventions. Electromagnetic navigation is most convenient for interventions that do not require fixation of the patient's head, in particular for CSF shunting procedures, drainage of various space-occupying lesions (cysts, hematomas, and abscesses), and optimization of the size and selection of options for craniotomy. In repeated interventions, disruption of the normal anatomical relationships and landmarks necessitates application of neuronavigation systems in almost mandatory manner. The use of electromagnetic navigation does not limit application of the entire range of necessary intraoperative neurophysiological examinations at appropriate surgical stages. Succession in application of neuronavigation should be used to get adequate test results.

[A rare case of diencephalic cachexia in an adult female with cranio-pharyngioma]. / Redkii sluchai razvitiia diéntsefal'noi kakheksii u vzrosloi zhenshchiny s kraniofaringiomoi.

Diencephalic cachexia (DС) is progressive weight loss despite a normal caloric intake and a satisfactory state of health, which is caused by hypothalamic lesions. This is a rare (about 100 cases were reported) and potentially fatal disorder of unknown pathogenesis. At present, there is no effective pharmacological therapy for the disorder. Cachexia may regress only if the tumor reduces in size, therefore the timely diagnosis and treatment are of vital importance for the patient. DС is typical of early childhood, and only a few cases have been reported in adults. We present a rare case of DС in a 24-year-old female with papillary craniopharyngioma.

[Extended endoscopic endonasal posterior (transclival) approach to tumors of the clival region and ventral posterior cranial fossa. Part 1. Topographic and anatomical features of the clivus and adjacent structures]. / Éndoskopicheskii éndonazal'nyi zadnii rasshirennyi (transklival'nyi) dostup k opukholiam oblasti skata i ventral'nykh otdelov zadnei cherepnoi iamki. Chast' 1. Topografo-anatomicheskie osobennosti skata i pogranichnykh s nim obrazovanii.

OBJECTIVE: to describe the main topographic and anatomical features of the clival region and its adjacent structures for improvement and optimization of the extended endoscopic endonasal posterior (transclival) approach for resection of tumors of the clival region and ventral posterior cranial fossa. MATERIAL AND METHODS: We performed a craniometric study of 125 human skulls and a topographic anatomical study of heads of 25 cadavers, the arterial and venous bed of which was stained with colored silicone (the staining technique was developed by the authors) to visualize bed features and individual variability. Currently, we have clinical material from more than 120 surgical patients with various skull base tumors of the clival region and ventral posterior cranial fossa (chordomas, pituitary adenomas, meningiomas, cholesteatomas, etc.) who were operated on using the endoscopic transclival approach. RESULTS: We present the main anatomical landmarks and parameters of some anatomical structures that are required for performing the endoscopic endonasal posterior approach. The anatomical landmarks, such as the intradural openings of the abducens and glossopharyngeal nerves, may be used to arbitrarily divide the clival region into the superior, middle, and inferior thirds. The anatomical landmarks important for the surgeon, which are detected during a topographic anatomical study of the skull base, facilitate identification of the boundaries between the different clival portions and the C1 segments of the internal carotid arteries. The superior, middle, and inferior transclival approaches provide an access to the ventral surface of the upper, middle, and lower neurovascular complexes in the posterior cranial fossa. CONCLUSION: The endoscopic transclival approach may be used to access midline tumors of the posterior cranial fossa. The approach is an alternative to transcranial approaches in surgical treatment of clival region lesions. This approach provides results comparable (and sometimes better) to those of the transcranial and transfacial approaches.

[The extended endoscopic endonasal transsphenoidal approach in surgery for epidermoid cysts of the chiasmatic region]. / Ispol'zovanie rasshirennogo transsfenoidal'nogo éndoskopicheskogo éndonazal'nogo dostupa v khirurgii épidermoidnykh kist khiazmal'noi oblasti.

Surgical treatment for epidermoid cysts of the chiasmatic region is a challenge because of the tendency to a massive spread of epidermoid masses through the cerebrospinal fluid pathways and a significant lesion deviation from the midline. PURPOSE: To analyze capabilities of the extended endoscopic endonasal transsphenoidal approach in surgery for epidermoid cysts. MATERIAL AND METHODS: The study included 6 patients with epidermoid cysts of the chiasmatic region who were operated on using the extended anterior endoscopic endonasal transsphenoidal approach at the Burdenko Neurosurgical Institute in the past 5 years. RESULTS: Epidermoid masses were completely removed in 5 patients; in none of the cases, complete removal of the epidermoid cyst capsule was achieved. There were no cases of vision deterioration and the development of new focal neurological symptoms. One female patient developed hypopituitary disorders in the postoperative period. There was no recurrence of epidermoid cysts during follow-up. CONCLUSION: Removal of epidermoid cysts of the chiasmatic region using the extended anterior endoscopic transsphenoidal approach may be an alternative to transcranial microsurgery.

[Cerebrospinal fluid rhinorrhea in primary treatment of large and giant prolactinomas with dopamine agonists]. / Nazal'naia likvoreia pri pervichnom lechenii bol'shikh i gigantskikh prolaktinom agonistami dofamina.

At present, pharmacological therapy of prolactinomas with dopamine agonists (DAs) is considered the treatment of choice. In most cases, giant prolactinomas respond to treatment with dopamine agonists and decrease in size during the first months of the treatment. One of the rare but dangerous complications of conservative treatment of prolactinomas with invasive growth is cerebrospinal fluid rhinorrhea. MATERIAL AND METHODS: We present a retrospective analysis of 15 patients with macropropactinomas who underwent surgery for cerebrospinal fluid rhinorrhea developed due to primary therapy with dopamine agonists at the Burdenko Neurosurgical Institute (BNI) in the period between 2005 and 2015. All patients had large and giant tumors (according to the classification adopted at the BNI). When cerebrospinal fluid rhinorrhea was detected, patients were hospitalized to the BNI for examination, detection of a CSF fistula, reconstruction of a defect, and resection (if possible) of the tumor. RESULTS: In the period between 2005 and 2015, 15 patients (8 males and 7 females) with prolactinomas of a large and giant size at the onset of conservative therapy underwent surgery for cerebrospinal fluid rhinorrhea at the BNI. All patients underwent transnasal reconstruction of a skull base defect, with 13 out of 15 patients undergoing simultaneous resection of the tumor. After tumor resection, reconstruction was performed using auto-fat, fascia, and glue (in 8 cases). In the remaining cases, apart from auto-fat, fascia, and glue, a mucoperiosteal flap and auto-bone were used. Fourteen patients were followe-up. In 13 cases, there was no relapse of cerebrospinal fluid rhinorrhea after skull base reconstruction. In 1 case, there was a relapse of cerebrospinal fluid rhinorrhea. CONCLUSION: Conservative treatment of patients with giant prolactinomas should be performed under regular control of ENT doctors and neurosurgeons for timely detection and surgical treatment of cerebrospinal fluid rhinorrhea.

[Transient enlargement of craniopharyngioma cysts after stereotactic radiotherapy and radiosurgery]. / Tranzitornoe uvelichenie ob''ema kist kraniofaringiom posle stereotaksicheskoi luchevoi terapii i radiokhirurgii.

Stereotactic radiotherapy/radiosurgery (RT/ES) is an effective technique for treating craniopharyngiomas (CPs). However, enlargement of the cystic part of the tumor occurs in some cases after irradiation. The enlargement may be transient and not require treatment or be a true relapse requiring treatment. MATERIAL AND METHODS: In this study, we performed a retrospective analysis of 79 pediatric patients who underwent stereotactic RT or RS after resection of craniopharyngioma. RESULTS: Five-year relapse-free survival after complex treatment of CP was 86%. In the early period after irradiation, 3.5 months (2.7-9.4) on average, enlargement of the cystic component of the tumor was detected in 10 (12.7%) patients; in 9 (11.4%) of them, the enlargement was transient and did not require treatment; in one case, the patient underwent surgery due to reduced visual acuity. In 8 (10.1%) patients, an increase in the residual tumor (a solid component of the tumor in 2 cases and a cystic component of the tumor in 6 cases) occurred in the long-term period after irradiation - after 26.3 months (16.6-48.9) and did not decrease during follow-up in none of the cases, i.e. continued growth of the tumor was diagnosed. A statistical analysis revealed that differences in the terms of transient enlargement and true continued growth were statistically significant (p<0.01). CONCLUSION: Enlargement of a craniopharyngioma cyst in the early period (up to 1 year) after RT/RS is usually transient and does not require surgical treatment (except cases where worsening of neurological symptoms occurs, or occlusive hydrocephalus develops).