[Quantitative analysis of orbit volume and eyeball position after resection of hyperostotic sphenoid wing meningioma and simultaneous orbital wall reconstruction using individual technologies]. / Kolichestvennyi analiz ob"emov glaznits i pozitsii glaznykh yablok posle udaleniya giperostoticheskikh meningiom kryl'ev osnovnoi kosti i odnomomentnoi rekonstruktsii stenok glaznitsy s ispol'zovaniem individual'nykh tekhnologii.

OBJECTIVE: To conduct a quantitative analysis of orbit volume at different stages of preparation and surgical treatment of patients with cranio-orbital meningiomas undergoing resection with simultaneous orbital wall reconstruction using 3D modeling and 3D printing technologies. MATERIAL AND METHODS: A prospective cohort non-randomized study included 24 patients with cranio-orbital meningiomas. The volumes were measured by segmenting the orbital structures using the planimetric method in the Inobitec PRO software package. Three expert neurosurgeons independently performed these measurements. The implants were modeled in Blender software. We used the intraclass correlation coefficient (ICC) and global similarity index (GSI) to analyze interrater agreement and ensure reproducibility of analysis. RESULTS: Interrater agreement on orbital markings was very high for both metrics (ICC and GSI). The ICC (A,3) for intact orbit volume was 0.99 (95% CI 0.981; 0.996, p=1.9962018^{-33}), 0.99 (95% CI 0.983; 0.996, p=1.903203^{-34}) for damaged orbit volume at the preoperative stage, 0.99 (95% CI 0.979; 0.995, p=3.5939828^{-32}) for damaged orbit volume at the stage of modeling of resection and reconstruction, 0.99 (95% CI 0.978; 0.995, p=1.1048941^{-30}) for damaged orbit volume in postoperative period. The ICC for measurements related to EI was 0.94-0.97 (very high). This analysis revealed a strong inverse relationship between EI and volume index at the preoperative stage (rho= -0.55, p=0.004987), as well as between dynamics of EI and volume indexes in perioperative period (rho= -0.59, p=0.003). We found significant relationship (p=0.006757) between implant displacement in the area of lateral orbital wall and differences of actual and theoretical volumes. CONCLUSION: The proposed method of planimetric contouring and segmentation of orbital volumes is highly accurate and reproducible. Significant patterns allow us to develop predictive models for preliminary calculation of target volume of the damaged orbit.

[Domestic software, medical devices and materials in surgery for hyperostotic craniofacial meningiomas]. / Primenenie otechestvennogo programmnogo obespecheniya, meditsinskikh izdelii i materialov v khirurgii giperostoticheskikh kraniofatsial'nykh meningiom. (Klinicheskii sluchai i obzor literatury).

OBJECTIVE: The modern concept of resection of hyperostotic craniofacial meningiomas involves the desire for one-stage surgery with excision of tumor and simultaneous extensive skull defect closure. MATERIAL AND METHODS: The authors present skull defect closure with an individual implant after resection of cranioorbital meningioma in a 61-year-old man. The neoplasm was accompanied by exophthalmos and eyelid edema. The patient underwent simultaneous microsurgical resection and skull reconstruction with an individual implant. At discharge (7 days after surgery), exophthalmos regressed to 3 mm. After 3 months, ophthalmologist revealed complete regression of exophthalmos. RESULTS: Domestic software and 3D printers were used for implant modeling and preparing the necessary physical models and molds. We intraoperatively used domestic polymer and titanium fixation systems for manufacturing and fixation of implant. CONCLUSION: This clinical case confirms that resection of hyperostotic craniofacial meningioma with simultaneous bone defect closure using domestic analogues of software, technical equipment, materials and methods is possible at all stages of this procedure.

[Complicated course of the postoperative period with the development of epidural hygroma and intracranial hypotension after removal of cranio-orbital meningioma. Clinical case and literature review]. / Oslozhnennoe techenie posleoperatsionnogo perioda s razvitiem epidural'noi gigromy i vnutricherepnoi gipotenzii posle udaleniya kranioorbital'noi meningiomy. Klinicheskii primer i obzor literatury.

Surgical removal of cranio-orbital meningiomas is an effective method of treating this pathology. Modern surgical techniques and technologies make it possible to perform operations with a low risk of complications. Lumbar drainage or repeated lumbar punctures are often used intraoperatively or in the early postoperative period to prevent nasal CSF leak; this rarely leads to the development of significant neurological symptoms. We present a case of the development of severe intracranial hypotension with the formation of a subdural hygroma in the early postoperative period after removal of a cranio-orbital meningioma in a 41-year-old patient. The operation was performed using an individual model and molds for simultaneous reconstruction of the bone defect with an implant made of polymethyl methacrylate. On the 1st and 2nd days after surgery, lumbar punctures were performed. From the 2nd day there was a progressive deterioration with the development of symptoms characteristic of intracranial hypotension. Computed tomography revealed an increasing displacement of the midline structures of the brain and an increasing volume of epidural fluid accumulation in the area of surgical intervention. Magnetic resonance imaging revealed characteristic signs of intracranial hypotension. Conservative treatment (bed rest, active hydration) had no effect. On the 6th day after surgery, an epidural blood patch procedure was performed and closed external drainage of the epidural hygroma was performed, and a rapid regression of neurological symptoms was noted. Our experience and literature data indicate that it is necessary to remember the possibility of developing clinically significant intracranial hypotension even after a single lumbar puncture. The formation of hygromas in the surgical area is characteristic of intracranial hypotension, but in most cases does not require additional surgical intervention and does not have a negative impact on the outcome of treatment. Conservative treatment of intracranial hypotension is the first choice and often sufficient. If there is no effect and the patient's condition worsens, it is necessary to perform an epidural blood patch procedure.

[Molecular genetic features of meningiomas]. / Molekulyarno-geneticheskie osobennosti meningiom.

Meningioma is the most common primary tumor of the central nervous system. Traditional classification is based on histological properties of tumors and distinguishes different grades of meningioma malignancy. However, knowledge about different molecular mechanisms of tumor provided new data on genetic features of meningiomas. The authors analyze current available data on the main driver mutations, new classifications based on molecular genetic characteristics and potential targets for therapy.

[Dural defect closure after resection of cranioorbital meningiomas]. / Rekonstruktsiya defektov tverdoi mozgovoi obolochki posle udaleniya kranioorbital'nykh meningiom.

Dural defect closure after resection of cranioorbital meningiomas has its own specifics. Extended malignant lesions and common large bone defects involving various anatomical regions require multiple implants or implants with complex geometry. The features of this stage of reconstruction were described in the previous issue of the Burdenko Journal of Neurosurgery. At the same time, contact of implant with nasal cavity and paranasal sinuses dictates additional requirements for tightness of soft tissue reconstruction and inertness of material. In this review, we describe modern and historically interesting methods of reconstruction of soft tissue defects following resection of cranioorbital meningioma. OBJECTIVE: To summarize and analyze available literature data on reconstruction of soft tissue defects following resection of cranioorbital meningioma. MATERIAL AND METHODS: The authors reviewed available data on reconstruction of soft tissue defects after resection of cranioorbital meningiomas. Effectiveness of reconstruction techniques and safety of materials were analyzed. RESULTS: The authors analyzed 42 available full-text articles. Features of growth and natural course of cranioorbital meningioma, methods of soft tissue defects closure, modern materials and sealing compositions are described. Considering these data, the authors proposed the algorithms for selecting materials for dural reconstruction after resection of cranioorbital meningioma. CONCLUSION: Improvement of surgical technique, development of new materials and technologies increase the efficiency and safety of dural defect closure. Nevertheless, high incidence of complications associated with dura mater repair necessitates further research in this area.

[Bone defect closure after resection of sphenoorbital meningioma]. / Rekonstruktsiya kostnykh defektov posle udaleniya kranioorbital'nykh meningiom.

Sphenoorbital meningiomas (SOM) are a subgroup of skull base tumors with soft tissue component in the orbit and anterior and/or middle cranial fossa. According to different authors, SOMs account for 2-12% of all intracranial meningiomas. Reconstruction of bone defects after resection of SOM has own nuances. Along with cranial vault repair, patients encounter with cosmetic defects following facial skull lesion, ophthalmic symptoms due to orbital defects, dental and functional problems associated with opening of the mouth in case of damage to maxilla and mandible. Predominant infiltrative growth of tumor and common large bone defects involving various anatomical regions require multiple implants or implants with complex shape. Moreover, contact of implantation area with nasal cavity and paranasal sinuses requires additional impermeability of soft tissue reconstruction and inertness of materials. OBJECTIVE: To summarize available modern data on bone defect closure after resection of SOM. MATERIAL AND METHODS: The authors reviewed available data on bone defect closure after resection of SOM. Effectiveness of modern methods of reconstruction and safety of materials were assessed. RESULTS: We analyzed 96 available references. Technical features of tumor resection, materials used for bone defect closure and modern possibilities of 3D technologies in reconstructive surgery were described. The authors proposed the algorithms for selecting the materials for bone defect closure after resection of SOM. CONCLUSION: Improvement of surgical technique and development of new materials and technologies significantly improve cosmetic and functional results. A large percentage of negative ophthalmologic outcomes and high risk of complications in SOM surgery require further studies and elaboration of modern techniques.

[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.

[Results of surgical treatment of skull-base primary malignant tumors with intracranial invasion]. / Rezul'taty khirurgicheskogo lecheniia pervichnykh zlokachestvennykh opukholei osnovaniia cherepa s intrakranial'nym rasprostraneniem.

OBJECTIVE: Analysis of factors affecting life expectancy at patients with primary malignant tumors of anterior and middle parts of the skull base with intracranial invasion. MATERIAL AND METHODS: 139 patients (47 women and 92 men) with primary malignant tumors of the anterior and middle parts of the skull base with intracranial invasion (stage T4 according to TNM classification or stage C according to Kadish classification for estesioneuroblast ) were treated at the NMRCN Burdenko for the period from 2004 till 2018. The study was conducted by the method of total sampling. The observations are divided into 2 groups: primarily operated (group I) and repeatedly operated (group II). RESULTS: The average age in both groups was 50 years. In most (64.7%) cases, the tumor affected the medial sections of the base of anterior and middle cranial fossae, and in 35.3% of cases it was localized laterally. All tumors were classified to T4 stage according to TNM classification or (9 olfactory neuroblastomas) to stage C according to Kadish classification. DISCUSSION: The impact on life expectancy was largely provided by postoperative radiation therapy, the repeated nature of operation, and the presence of brain infiltration. In the total cohort of patients 5-year OS, 5-year RVS, 5-year-old IDF and 5-year LC were 50.7, 35, 54.2 and 36.4%, respectively. In group I, the medians OS and IDF were equal and amounted to 138.3 months. The median RVS was 43.8 months. 5-year OS equal to 63.6%, 5-year RVS - 40.8%, 5-year-IDF - 64.8%, 5-year LC was up to 65.7%. The survival rate in the analyzed cohort for 1, 2, 3 years was 81.4, 71.8 and 67.8%, respectively. In group II, the treatment results for the group of repeatedly treated patients were significantly worse. There were no cases of 5-year survival. The 1-, 2-, and 3-year survival rates were 59.3, 50.8 and 31.8%, respectively. The median OS was 27.1 months, IDF was 27.1 months, RVS was 18.2 months, and LC was 9.1 months. CONCLUSION: The results and analysis of literature justify the feasibility of surgical treatment of patients with malignant tumors of craniofacial localization at T4 stage. The purpose of surgical intervention should be: elimination of the immediate threat to the patient's life due to edema and dislocation of the brain; the maximum possible removal of tumor tissue (cytoreduction); if possible, the elimination of the most significant symptoms for the patient (pain, nasal breathing disorders, cosmetic defect). If there are special reserves, it is obligatory to include radiation and chemotherapy in the treatment process.

[Individual preoperative 3D modeling of vascular brain pathology]. / Individual'noe predoperatsionnoe 3D-modelirovanie sosudistoi patologii golovnogo mozga.

The possibility of segmenting three-dimensional objects by DICOM-series is well known and available both on specialized workstations and on personal computers. The technique, however, is relatively rarely used in clinical practice, and we believe that the benefits of preoperative preparation using segmented 3D models are underestimated. The article is devoted to our experience in using segmentation of anatomical structures based on CT and MRI for preoperative preparation for surgical operations performed in neurosurgical departments on patients with vascular pathology. The paper discusses the types and possibilities of segmentation, provides some examples describing the clinical use of the technique.

[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.