[Optic canal stenosis in Crouzon syndrome: a case report and literature review]. / Stenoz zritel'nykh kanalov pri sindrome Kruzona: klinicheskii sluchai i obzor literatury.

BACKGROUND: Incidence of Crouzon syndrome is 1 per 25.000-31.000 newborns. This syndrome is extremely rarely accompanied by optic canal stenosis. OBJECTIVE: To present a patient with Crouzon syndrome and optic canal stenosis, to discuss the management of such patients considering own and literature data. MATERIAL AND METHODS: A 6-year-old boy presented with Crouzon syndrome (verified by molecular genetic research, i.e. FGFR2 gene mutation). The patient underwent 3 surgeries for craniosynostosis and hydrocephalus. Nevertheless, visual acuity progressively decreased despite patent ventriculoperitoneal shunt. Examination revealed severe decrease in visual functions with optic disc congestion under secondary atrophy. MRI data on subarachnoid CSF accumulation over both optic nerves potentially indicated optic canal stenosis. This assumption was confirmed by 3D CT. RESULTS: The patient underwent decompression of both optic canals with subsequent improvement of visual functions. CONCLUSION: Vision decrease following Crouzon syndrome may be due to optic canal stenosis. Decompression may be effective, even in long-term course of disease, and improve visual functions.

[3D modeling for planning of minimally invasive approach to the orbit]. / Ispol'zovanie 3D-modelirovaniya dlya planirovaniya minimal'no invazivnogo dostupa k oblasti orbity. Sluchai iz praktiki i obzor literatury.

OBJECTIVE: To demonstrate own experience in 3D modeling for planning of minimally invasive approach to the orbit and anterior skull base. MATERIAL AND METHODS: A 17-year-old patient admitted to the Department of Pediatric Neurosurgery with complaints of decreased visual acuity of the left eye, lacrimation and exophthalmos. MRI revealed a tumor of the left orbit. We have preoperatively modeled frontoorbital region, anterior skull, as well as eyeball and tumor within the same model. Considering young age and potentially favorable prognosis of disease, we preferred a minimally invasive intervention (microsurgical resection of tumor through minimally invasive frontoorbital access). RESULTS: Total resection of tumor was followed by examination of anterior skull base. There was postoperative regression of visual disturbances, lacrimation and exophthalmos. Sutures were removed after 5 days, and the patient was discharged. CONCLUSION: Minimally invasive frontoorbital access is adequate for approach to the orbit, anterior and middle cranial fossa, adequate resection of orbital tumor and examination of anterior skull base. 3D modeling is an additional preoperative tool to improve the quality of preoperative planning and facilitate intraoperative navigation.

[Combination of tumors of different histogenesis in pediatric neurosurgery]. / Sochetanie opukholei razlichnogo gistogeneza v detskoi neirokhirurgii.

Multiple gliomas are determined by synchronous two or more tumors located in different brain regions. It is important to distinguish multiple primary tumors and metastatic brain lesion. In the first case, tumor spread can`t be explained by dissemination along the cerebrospinal fluid pathways, commissural fibers or local metastases. Multiple primary tumors with different histological structures are called bidermal neoplasms. Surgery is preferred in these patients with severe symptoms. The purpose of surgery is maximum resection of tumor. Follow-up may be advisable for small tumors without clinical manifestations. Treatment of multiple gliomas includes surgery, radiotherapy and chemotherapy. Multiple tumor process in children is much more severe compared to a single neoplasia that requires neurological and neuroimaging control and determines treatment strategy. The authors report 3 children with multicentric gliomas, discuss the various aspects of diagnosis and treatment of multiple gliomas and formulate the recommendations for the treatment based on own clinical experience and literature data.

[Redo surgery in children with epilepsy]. / Povtornye operatsii v khirurgii epilepsii u detei.

OBJECTIVE: To analyze the causes of ineffective operations and the results of redo surgery in children with recurrent epileptic seizures. MATERIAL AND METHODS: The results of redo surgery were analyzed in 41 (10.6%) out of 387 children with drug resistant epilepsy treated surgically at the Russian Polenov Neurosurgical Institute for the period from 1994 to 2014. Patients with recurrent epilepsy after temporal resection (n=20), extratemporal resection (n=7), multifocal resection (n=6), callosotomy and stereotaxic destruction (n=8) were selected for analysis. RESULTS: Seizure-free period ranged from early postoperative period to 4 years. According to MRI data, lesions were not completely resected during primary surgery in 23 (56.1%) children. The causes of inefficiency of primary operations were inaccurate identification of epileptic focus in 15 (36.6%) patients; incomplete resection of epileptogenic and / or epileptic foci or incomplete disconnection of paroxysmal activity distribution pathways in 14 (34.1%) cases; epileptic foci de novo in 8 (19.5%) cases; inadequate surgical strategy in 4 (9.8%) patients. Redo surgery usually implied an extended previous resection in 34 (82.9%) patients. Engel I outcome after 3 years was achieved in 41.1% of patients, after 5 years - 38.3%, after 10 years - 36.4%. CONCLUSION: Redo surgery is quite effective and minimally traumatic. Therefore, patients with recurrent epileptic seizures should be considered as candidates for repeated operations if previous interventions turned out to be ineffective.

[Skull defect repair in children using a 3D-printing technology]. / Kranioplastika defektov cherepa u detei s ispol'zovaniem tekhnologii 3D-pechati.

Currently, 3D-printing technologies are increasingly used in neurosurgery. Active development of this approach is valuable to improve preoperative planning, intraoperative navigation, and manufacturing of realistic training models. In this manuscript, the authors report an experience of the pediatric neurosurgical department of the Almazov National Medical Research Center regarding 3D-printing technologies in manufacturing of individual implants for skull defect closure. The main aspects of this technology, advantages and disadvantages are considered. Moreover, the authors describe several cases of creating individual implants for children with skull defects of various origins, dimensions and complexity.

[Clinical, structural and functional features of paroxismal syndrome in insular and temporal lobe tumors]. / Klinicheskie i strukturno-funktsional'nye osobennosti paroksizmal'nykh rasstroistv, obuslovlennykh opukholyami ostrovkovoi i visochnoi dolei.

OBJECTIVE: To analyze the characteristics of paroxysmal syndrome in insular and temporal lobe tumors, to determine their relationship with the histological structure of tumor, to assess the effect of tumor growth nature on severity of disease. MATERIAL AND METHODS: A retrospective analysis enrolled 80 patients aged 11 - 80 years with insular and temporal lobe tumors and symptomatic epilepsy. All patients underwent surgery at the Polenov National Research Neurosurgery Center in Almazov National Medical Research Center for the period from 2012 to 2018. RESULTS: The main group consisted of 29 patients with tumors of temporal and insular lobes. Control group of 51 patients with temporal gliomas was formed for comparative analysis. It was found that involvement of insular lobe into paroxysmal syndrome is characterized by attacks with a motor component, somatosensory paroxysms, vegetative manifestations (respiratory attacks, salivation, nausea), speech disorders and taste hallucinations. Derealization, motor arrest and déjà vu/jamis vu paroxysms were more common in patients with temporal lobe lesion. Neoplastic lesion of the insular lobe shortens the period between manifestation of paroxysms and surgical treatment. Moreover, this type of disease is characterized by higher incidence of seizures compared to isolated temporal lobe tumors.

[Arteriovenous malformations and epileptic seizures in children: risk factors of seizures and efficacy of their control depending on the surgical treatment modality]. / Arteriovenoznye mal'formatsii i épilepticheskie pristupy u detei: faktory riska razvitiia pristupov i éffektivnost' ikh kontrolia v zavisimosti ot metoda khirurgicheskogo lecheniia.

Epileptic seizures are some of the most frequent manifestations of cerebral AVMs in children. Poor control of seizures can significantly affect patients' quality of life. In this case, factors that are associated with the development of seizures and affect the efficacy of their control upon treatment of cerebral AVMs are not well understood. PURPOSE: The purpose of this study was to identify risk factors for the development of epileptic seizures as well as factors associated with a seizure-free outcome of AVM treatment in children. MATERIAL AND METHODS: We analyzed the results of examination and treatment in 89 patients with cerebral AVMs aged 1 to 17 years. RESULTS: Factors associated with the development of epileptic seizures in cerebral AVMs in children included male gender of the child, a large size of AVM and its superficial location, as well as localization of the pathology in the frontal and temporal lobes of the brain and draining varices. Regression of seizures after surgery was more often observed in the case of microsurgical and/or complex surgical treatment and complete exclusion of the AVM as well as in cases of rare attacks and a short course of the disease. CONCLUSION: Complex and microsurgical treatment of AVMs in children provides effective control of epileptic seizures, which is obviously associated with complete exclusion of the AVM and removal of the epileptic focus located near the AVM.

[Methods to assess competence of indirect cerebral revascularization in children]. / Metody otsenki sostoiatel'nosti nepriamoi revaskuliarizatsii golovnogo mozga u detei.

The use of catheterization cerebral angiography (CCA) to assess collateral blood flow through an indirect anastomosis is traumatic for children, uses a high radiation dose, and requires anesthetic care in most cases. AIM: we aimed to compare the capabilities of triplex ultrasound (TU) of vessels, magnetic resonance angiography (MRA), computed tomography angiography (CTA), and CCA in assessing the competence of indirect cerebral revascularization (ICR) in children. MATERIAL AND METHODS: ICR was performed in 18 children in 24 hemispheres (24 operations). The results were evaluated by Matsushima classification-based comparison of the data of preoperative and postoperative clinical examinations, TU of the superficial temporal artery, magnetic resonance imaging (MRI) and computed tomography (CT) of vessels, and selective cerebral angiography. RESULTS: After surgery, improvements in the neurological and neuropsychological status were assessed. Matsushima grade A collaterals were found in 12 (50%) cases, grade B collaterals were present in 3 (13%) cases, grade C collaterals were present in 7 (29%) cases, and grade D collaterals were detected in 1 (4%) case; in 1 (4%) case, the superficial temporal artery was not enhanced. MR angiography visualized 18 (75%) indirect anastomoses, CT angiography revealed 4 indirect anastomoses, and TU visualized 4 indirect anastomoses. Comparison of preoperative and postoperative TU data for the superficial temporal artery revealed significant changes in blood flow in the form of increased rate indices and a decreased resistance index; mean values of indices for each angiographic class of revascularization and significant differences in pre- and postoperative observations were calculated. CONCLUSION: Examination of ICR competence using CCA is necessary in the presence of persistent clinical signs of chronic cerebral circulatory insufficiency, absence of increased blood flow and decreased peripheral resistance in the superficial temporal artery, and lack of anastomosis according to MRA. The most optimal techniques for postoperative examination are MRA with perfusion and diffusion maps and TU.

[Intraoperative fluorescence diagnosis using 5-aminolevulinic acid in surgical treatment of children with recurrent neuroepithelial tumors]. / Rezul'taty intraoperatsionnoi fluorestsentnoi diagnostiki s ispol'zovaniem 5-aminolevulinovoi kisloty pri khirurgicheskom lechenii detei s retsidivami neiroepitelial'nykh opukholei.

AIM: To analyze the efficacy and safety of 5-aminolevulinic acid for intraoperative fluorescence diagnosis (FD) during repeated surgery for recurrent neuroepithelial tumors (NETs) in children. MATERIAL AND METHODS: We performed a retrospective analysis of the results of recurrent NET resection in 13 children aged from 3 to 17 years in the period between December 2013 and May 2015. The source of 5-ALA was a drug "Alasens" that was administered at a dose of 20 mg/kg of body weight 4 h before the beginning of tumor resection. A visual scale was used to evaluate the fluorescence intensity. The drug was used with the informed consent of the child's parents and approval of the Polenov Neurosurgical Institute ethics committee. All patients underwent complex clinical and introscopic examination in the pre- and postoperative periods and a repeated histological tumor examination. RESULTS: There was no fluorescence in 4 cases (Gr I in 2 cases; Gr II in 2 cases). Grade 1 fluorescence (Gr II) was observed in one case, and grade 2-3 fluorescence was observed in the remaining 8 patients. Total and subtotal tumor resection was achieved in 11 (84.6%) of 13 patients. There were no clinically significant adverse effects. A transient increase in transaminases was observed in 2 patients. Two girls had an elevated photosensitivity to light for two days. CONCLUSION: FD is a safe technique in childhood and can improve intraoperative detection of NET during its repeated growth as well as differentiate the tumor from pathological tissues of non-tumorous nature, which increases completeness of blastomatous tissue removal. However, the character and intensity of fluorescence may change in recurrent NETs. Further research is required to investigate the FD effectiveness in various age patients with tumors of a different histological structure and malignancy in the case of both primary and recurrent lesions.

[Surgical treatment outcomes in children with tethered spinal cord syndrome. A prognosis on the basis of spinal 3T MRI tractography]. / Rezul'taty khirurgicheskogo lecheniya detei s sindromom fiksirovannogo spinnogo mozga. Prognoz na osnovanii dannykh spinal'noi 3Tl MRT-traktografii.

AIM: The study objective was to identify factors affecting surgical treatment outcomes in children with tethered cord syndrome (TCS). MATERIAL AND METHODS: The study included 21 TCS patients aged 1 to 14 years who underwent tethered cord release. The preoperative and postoperative data of clinical and neurophysiological examination and high field (3T) MRI tractography of the caudal spinal cord were compared. RESULTS: Regression of the TCS clinical and electrophysiological signs and the lack of pathological changes in the spinal cord tracts were observed in patients with filum terminale abnormalities and caudal lipomas after surgery. In patients with secondary spinal cord tethering caused by scar formation after lumbosacral myelomeningocele repair, a motor deficit was related to the interruption level of the spinal tracts, and surgical treatment did not lead to significant regression of the TCS clinical and electrophysiological signs. CONCLUSION: We consider the absence of pathological changes in the caudal spinal cord, based on spinal MRI tractography, as a favorable prognostic factor in TCS surgical treatment.

[Granulomatous inflammation in the bed of resected cerebral cavernoma in a child, caused by a hemostatic agent].

OBJECTIVE: The study presents a clinical observation of foreign body granuloma, which is rare productive inflammation, developed on treatment with a hemostatic material upon removal of cerebral cavernoma. MATERIAL AND METHODS: A 4-year-old boy operated on for left parietal lobe cavernoma was diagnosed with a mass lesion during a follow-up MRI examination 4 months after surgery. The patient was re-operated in connection with suspected abscess formation. The pathological tissue was subjected to the histological and immunohistochemical examination. RESULTS: Inflammation was accompanied by the formation of foreign body granulomas, and, in some areas, had immune nature with signs of focal destructive vasculitis, delayed maturation of the granulation tissue, and disturbance of the current organization and encapsulation processes. It is worth noting that granulomatous inflammation around a hemostatic material in the brain has no specific features during introscopy and mimics an abscess or tumor recurrence. CONCLUSION: The use of hemostatic materials upon resection of cerebral cavernous malformations may cause formation of granuloma mimicking disease relapse or abscess in the long term period. To prevent granulomatous inflammation, removal of a hemostatic material, if possible, from the surgical field is recommended when reliable hemostasis is achieved.