[Venous cerebral complications after microsurgery for complex aneurysms of the middle cerebral arteries]. / Venoznye tserebral'nye oslozhneniya mikrokhirurgicheskikh operatsii po povodu slozhnykh anevrizm srednikh mozgovykh arterii.

Microsurgeries are common for complex aneurysms of the middle cerebral artery (MCA). OBJECTIVE: To evaluate the incidence and types of venous cerebral disorders after microsurgeries for complex MCA aneurysms. MATERIAL AND METHODS: A retrospective study included 285 patients with complex MCA aneurysms between 2009 and 2020. Pterional craniotomy and transsylvian approach were used in all cases. Aneurysm clipping was performed in 230 cases, revascularization - 27, trapping without bypass - 17, reinforcement - in 11 cases. Computed tomography within 1-3 days after surgery recognized venous cerebral disorders as heterogeneous foci of abnormal brain density with unclear boundaries. These foci were crescent-shaped as a rule and located in deep and basal parts of the frontal lobes. RESULTS: Venous abnormalities occurred in 76 (26.7%) patients. Thirty-five (12.3%) patients had mild venous edema of the frontal lobe alone. In 35 (12.3%) patients, we found moderate disorders with focus in the frontal lobe and compression of anterior horn of the left lateral ventricle with or without hemorrhagic imbibition. Severe disorders occurred in 6 (2.1%) patients with lesion extending to the frontal, insular and temporal lobes. These lesions were accompanied by hemorrhagic imbibition, and lateral dislocation exceeded 5 mm. CONCLUSION: Careful dissection of veins in Sylvian fissure with preservation of bridging veins is likely to reduce the risk of this complication. Cauterization of a large vein in Sylvian fissure should be followed by careful hemostasis within frontal or temporal cortex. Bleeding and cortical tension can indicate intracerebral hematoma whose likelihood is higher in patients with venous cerebral disorders.

[Comparison of polymethyl methacrylate skull implant fixation by three types of titanium fasteners]. / Sravnenie sposobov fiksatsii implantov cherepa iz polimetilmetakrilata tremya vidami titanovykh krepezhei.

OBJECTIVE: To evaluate mechanical strength of three methods of polymethyl methacrylate skull implant fixation in two experimental models. MATERIAL AND METHODS: The first experiment was performed on a plastic model that was as close as possible to bone in structural characteristics. The second experiment was performed on a biological specimen (a ram's head). We assessed the quality of implant fixation to bone window edges by craniofixes, ties and microscrews and lateral intercortical screws. RESULTS: Craniofixes are feasible for small flat flaps, but not advisable for wide highly curved implants. They are also the most expensive method of fixation. Implant fixation by ties and microscrews is a universal method comparable in price to craniofix. Lateral intercortical fixation is effective both for small flat implants and wide implants with large curvature. However, this method is not always applicable. CONCLUSION: Combined fixation by lateral intercortical screws and ties allows for the most effective fixation while reducing the overall price of consumables.

[Surgical treatment of intracranial aneurysms in acute period of hemorrhage in Hunt-Hess grade IV-V patients at Burdenko Neurosurgical Center between 2006 and 2020]. / Analiz rezul'tatov khirurgicheskogo lecheniya tserebral'nykh anevrizm v ostrom periode krovoizliyaniya u patsientov so stepen'yu tyazhesti Hunt­Hess IV­V v FGAU «Natsional'nyi meditsinskii issledovatel'skii tsentr neirokhirurgii im. akad. N.N. Burdenko¼ za 2006­2020 gg.

BACKGROUND: Management of patients in acute period of aneurysmal subarachnoid hemorrhage Hunt-Hess grade IV-V is still a complex and unsolved problem, especially regarding surgical treatment and various complications. OBJECTIVE: To analyze postoperative outcomes in patients undergoing surgery in acute period of aneurysmal subarachnoid hemorrhage Hunt-Hess grade IV-V between 2006 and 2020, as well as to assess various factors influencing treatment outcomes. MATERIAL AND METHODS: We analyzed 163 patients who underwent surgery within 21 days after aneurysmal subarachnoid hemorrhage Hunt-Hess grade IV-V. All patients were divided into 2 groups depending on the period: 2006-2011 (group 1) and 2012-2020 (group 2). RESULTS: Mortality reduced from 28.6% in group 1 to 8.3% in group 2. At the same time, incidence of vegetative state (GOS grade 2) increased from 4.8% to 17.4%. Incidence of outcomes GOS grade 3 - 5 was similar. CONCLUSION: Large or giant aneurysm, repeated preoperative subarachnoid hemorrhage, intraoperative aneurysm rupture and prolonged temporary clipping can impair postoperative outcomes in patients with hemorrhage Hunt-Hess grade IV-V. External ventricular drainage, intraarterial injection of verapamil, intracisternal administration of calcium channel blockers and active surgical tactics improve postoperative outcomes and reduce mortality.

[Microsurgical and endovascular treatment of residual and recurrent cerebral aneurysms]. / Osobennosti mikrokhirurgicheskogo i endovaskulyarnogo lecheniya rezidual'nykh i rekurrentnykh tserebral'nykh anevrizm.

Cerebral aneurysms are characterized by high risk of adverse outcome due to severe intracranial hemorrhages and their consequences. Aneurysm remnants after incomplete exclusion can cause hemorrhage. Filling of these fragments immediately after surgery is usually defined as residual aneurysms. Recurrent aneurysms develop in the area of excluded aneurysm in long-term period after surgery. The authors analyze foreign and national literature data on the diagnosis and management of residual and recurrent aneurysms. Risk factors, the most common classifications, diagnostic methods and surgical treatment are presented.

[Thrombectomy without temporary clipping for giant partially thrombosed saccular aneurysms]. / Trombektomiya bez vremennogo klipirovaniya pri gigantskikh chastichno trombirovannykh meshotchatykh anevrizmakh.

Cerebral aneurysm thrombosis is one of the factors increasing the risk of microsurgical treatment. Thrombi and calcifications within the aneurysm neck prevent adequate clipping and should be removed before the procedure. At the same time, the process of thrombectomy is difficult and time consuming that increases duration of temporary arterial clipping and risk of cerebral ischemia. OBJECTIVE: To evaluate the results of thrombectomy without temporary arterial clipping for giant aneurysms of anterior brain circulation. MATERIAL AND METHODS: Four patients with giant partially thrombosed saccular aneurysms underwent thrombectomy without temporary clipping followed by neck clipping. In all cases, the aneurysm was thrombosed by more than 80-90% of its baseline volume, and aneurysm neck contained parietal thrombi from all sides. Mean duration of thrombectomy from aneurysm opening to bleeding and temporary clipping of the parent artery was 82 minutes, time of temporary clipping was about 12 minutes. RESULTS: Favorable clinical and radiological postoperative results were obtained in all patients. The authors present a scheme of surgical stages and video presentation involving the main surgical aspects of this procedure. CONCLUSION: Thrombectomy without temporary clipping of the parent artery is an effective technique for microsurgical treatment of giant partially thrombosed saccular intracranial aneurysms. Since most thrombi are removed without bleeding, duration of temporary blood flow discontinuation in the parent artery is significantly reduced. Therefore, we decrease the risk of cerebral ischemia. This technique can be useful in microsurgical treatment of complex aneurysms of the middle cerebral and internal carotid arteries, as well as other aneurysms.

[Intravascular hypothermia for cerebral ischemia after microsurgical clipping of complex MCA aneurysms]. / Vnutrisosudistaya gipotermiya pri tserebral'noi ishemii posle mikrokhirurgicheskogo klipirovaniya slozhnykh anevrizm srednei mozgovoi arterii.

Hypothermia for neuroprotection and correction of intracranial hypertension was described in both experimental and clinical studies. Effectiveness of hypothermia for improvement of functional outcomes in neurosurgical patients is still unclear despite the previous randomized trials. In available national and foreign literature, we found no trials devoted to hypothermia in patients with ischemia after surgical treatment of complex aneurysms of the middle cerebral artery (MCA). OBJECTIVE: To analyze the effectiveness of intravascular hypothermia in patients with ischemic cerebrovascular accidents in early postoperative period after microsurgical clipping of complex MCA aneurysms. MATERIAL AND METHODS: We present four patients with cerebral ischemia after microsurgical treatment of complex MCA aneurysms. In all cases, ischemic disorders developed immediately after surgery. We induced intravascular hypothermia 32-34 °C in all patients. CT-based volumetry of ischemia and edema foci was performed to objectively assess the dynamics of ischemic disorders. We carried out volumetry using segmentation of edema and ischemia foci (range 5-33 Hounsfield units). RESULTS: According to brain CT data, all four patients had enlargement of postoperative ischemic brain damage. Nevertheless, ICP was stable that made it possible to avoid decompressive craniotomy. CONCLUSION: Early hypothermia for acute ischemic injury after surgery for complex MCA aneurysms can reduce ischemic perifocal edema. This approach effectively reduces ICP and can exclude the need for decompressive craniotomy in some cases. No side effects of hypothermia justifies further research in this field.

[Unruptured asymptomatic brain aneurysms: modern approaches to the choice of surgical method and treatment outcomes]. / Nerazorvavshiesya bessimptomnye anevrizmy arterial'nykh sosudov golovnogo mozga: sovremennye podkhody k vyboru khirurgicheskogo metoda i rezul'taty lecheniya patsientov.

BACKGROUND: In recent years, significant attention has been paid to preventive vascular neurosurgery. Treatment of unruptured asymptomatic brain aneurysms is one of the sections of this surgery. OBJECTIVE: To evaluate treatment outcomes in patients with unruptured asymptomatic brain aneurysms who underwent treatment chosen on the basis of criteria adopted at the Burdenko Neurosurgery Center. MATERIAL AND METHODS: There were 2814 unruptured asymptomatic brain aneurysms in 2334 patients for the period from 1995 to 2019. RESULTS: Microsurgical operations for unruptured asymptomatic brain aneurysms were performed in 64.9% of cases, endovascular procedures - in 35.1% of patients. Endovascular operations were usually performed for ICA aneurysms and posterior aneurysms of circle of Willis. Microsurgical operations were mainly performed in patients with aneurysms of anterior and middle cerebral arteries. Favorable outcomes (GOS grade V-IV) were obtained in most patients (98.3%). Incidence of severe complications was similar in both groups, mortality rate was 0.3% and 0.4%, respectively. CONCLUSION: Currently, there is a tendency towards annual increase in the number of surgeries for unruptured brain aneurysms. Anatomical and morphological characteristics of aneurysm should be considered to achieve favorable clinical results. At the same time, comprehensive analysis of each case and identification of individual risk factors will eliminate serious complications of surgical treatment.

[Completeness of brain aneurysm exclusion according to CT angiography]. / Otsenka radikal'nosti mikrokhirurgicheskikh operatsii pri arterial'nykh anevrizmakh golovnogo mozga po dannym komp'yuternoi tomograficheskoi angiografii.

OBJECTIVE: To develop a classification of the completeness of brain aneurysm exclusion according to CT angiography for determining further diagnostic and curative strategy. MATERIAL AND METHODS: The study included 138 patients who had 164 brain aneurysms. Clipping was carried out at the Burdenko Neurosurgery Center in 2013-2017. Titanium clips were used in 111 cases, cobalt clips - in 53 patients. RESULTS: Completeness of brain aneurysm exclusion was assessed in 149 cases using CT angiography. In 15 cases, artifacts from cobalt clips impaired assessment. Total exclusion was achieved in 136 (91.3%) cases, subtotal (a remainder of residual neck) - in 10 (6.7%) cases, complete exclusion of the body and bottom (patent neck) - 2 (1.3%) patients, partial exclusion (partially patent bottom) - 1 patient (0.7%). In this series, a clip prevented complete contrast enhancement of brain aneurysm bottom in all cases. CONCLUSION: CTA is a reliable method for assessing the quality of exclusion of brain aneurysm in patients with implanted titanium clips. In case of cobalt clips, stratification depending on severity of CT artifacts should be performed for data interpretation. In some cases, artifacts impair visualization of the vessels adjacent to the clips. In these patients, direct cerebral angiography or dual-energy computed tomography scanners with metal artifact suppression programs should be recommended.Follow-up is recommended for patients with remnants of residual cervix. Redo surgery is indicated for completely patent neck, as well as partial or complete contrast enhancement of aneurysm bottom.

[Microsurgical resection of multiple unruptured cerebral AVMs. Case report and literature review]. / Mikrokhirurgicheskoe udalenie mnozhestvennykh nerazorvavshikhsya arteriovenoznykh mal'formatsii golovnogo mozga. Sluchai iz praktiki i obzor literatury.

Multiple brain arteriovenous malformations (AVMs) are extremely rare. We report a 26-year-old patient with paroxysmal symptoms. This was the first case in our center over 10 years (0.15% of all patients with brain AVM in this period). Microsurgical resection of AVM of the left temporal lobe was carried out at the first stage (Spetzler-Martin grade I). A month later, resection of AVM of the left parietal lobe (Spetzler-Martin grade III) after preliminary endovascular embolization was carried out. Early postoperative visual and mental disorders occurred after the second surgery and completely regressed within 1 month. Control angiography after the second operation confirmed total resection of both AVMs. Thus, staged microsurgical resection of two cerebral AVMs combined with preliminary endovascular embolization of more complex AVM was effective and ensured favorable clinical result. We analyzed the features of our clinical case and compared our findings with literature data.

[Arteriovenous malformations of the brain in children: treatment results for 376 patients]. / Arteriovenoznye mal'formatsii golovnogo mozga u detei: rezul'taty lecheniya 376 patsientov.

UNDEFINED: Cerebral arteriovenous malformations (AVM) are increasingly detected in children. OBJECTIVE: To estimate the risk of hemorrhage in children with AVM before and after treatment and evaluate the outcomes of various methods of AVM management in children. MATERIAL AND METHODS: This study included 376 patients with various cerebral AVM under the age of 18 years. There were 273 patients with intracranial hemorrhage (72.6%). RESULTS: Recurrent hemorrhages within the first month were registered in 1.1% of patients with angiomatous AVM prior to treatment and in 15.4% of patients with fistulous AVM. Microsurgical resection of AVM was performed in 135 (35.9%) patients. Total resection was achieved in 97.8% of cases. There were no mortality after microsurgical procedures. Endovascular treatment was applied in 79 (21%) patients. Total embolization was achieved in 29.1% of patients. One patient (1.3%) died after endovascular procedure. Radiosurgery was performed in 140 (37.2%) patients with total obliteration after a single fraction in 64.4% of patients. Favorable long-term outcomes (GOS grades V-IV) were achieved in 89.6% of patients with available follow-up data (n=182). Recurrent hemorrhages were registered in 6% of patients (3.3% after radiosurgery, 2.7% after endovascular treatment). One patient with recurrent hemorrhage died after radiosurgery. CONCLUSION: Early relapses of hemorrhage are not characteristic for children with cerebral AVM. Therefore, there are no indications for urgent surgery except for cases of intracerebral hematoma. In children, microsurgical treatment is preferred for angiomatous AVM, endovascular treatment - for fistulous AVM. Radiosurgery also ensures favorable outcomes. However, it is unreasonable to postpone AVM radiosurgical treatment in children with increased risk of recurrent hemorrhage considering relatively long period of post-radiation obliteration of AVM.

Intra-arterial Administration of Verapamil for the Prevention and Treatment of Cerebral Angiospasm.

From 2013 to 2017, at the Burdenko Institute of Neurosurgery, intra-arterial verapamil for treatment of cerebral vasospasm following intracranial hemorrhage after aneurysm rupture was administered to 35 patients (total 75 procedures). The age is from 8 to 77 years. All ruptured aneurysms were treated: in 26 cases with open approach-clipping-and in 9 cases with endovascular occlusion. The procedure was carried out from 0 to 11 days after the operation. Severity of spasm was assessed by angiography and TCDU. Efficacy of the administration was assessed by TCDU 1 h after the procedure and by clinical evaluation of the patient's condition. The dose of verapamil was 15-50 mg (on average 40 mg) per procedure/per carotid pool and depended on the data of TCDU and clinical and radiological picture. The procedure was performed repeatedly (1-5 times) according to the indications and depending on the patient's condition, with an interval of 24 h. The procedure was effective as a preventive measure for care of patients in the initial stage of cerebral ischemia and was ineffective with a formed focus of ischemia. Endovascular administration of verapamil for treatment of cerebral vasospasm is a safe technique which positively affects the overall recovery of such patients.

[Surgical treatment of patients with cerebral aneurysms in the acute stage of rupture: dynamics of results during 2006-2018]. / Khirurgicheskoe lechenie bol'nykh s anevrizmami sosudov golovnogo mozga v ostroi stadii razryva: dinamika rezul'tatov za 2006-2018 gg.

Treatment of cerebral aneurysms in the acute stage of subarachnoid hemorrhage (SRH) especially on the background of cerebral vasospasm continues to be a difficult task. OBJECTIVE: Assessment of dynamics of the surgical treatment results of patients with cerebral aneurysms in acute period of SRH. MATERIAL AND METHODS: A comparative analysis of the results of patients' surgical treatment in NMRCN Burdenko about aneurysm in 1-21 days after hemorrhage was made. The following periods were selected: 2006-2014 (343 patients) and 2015-2018 (356 patients). Most patients had microsurgical operations in both periods. The tactics of choosing the surgery time was the main difference between the periods: particularly in 2015-2018 period the surgery was not postponed at patients with severe. RESULTS: Analysing the post surgical mortality, it was found that since 2006 there is a consistent trend towards a decrease in the number of patients who died after surgery. When calculating the average post surgical mortality for the studied periods this trend is confirmed - number of lethal cases in 2015-2018 reliably decreased when comparing with 2006-2014 - from 6.8 till 3.2%; p=0.03. At the same time, the number of patients with outcome of vegetative status (from 0.3 till 5%). CONCLUSION: The tactics of surgical treatment of patients with cerebral aneurysms in the acute period of SRH regardless of severity of patient's condition and time of hemorrhage did not lead to worse treatment. In contrast, post surgical mortality rates show a consistent decline. We associate this fact with a number of changes that have occurred in the management and treatment of patients. In particular, we have high hopes for developing new approaches to the treatment of vasospasm, which remains the leading cause of lethal cases. More definite conclusions will be made at the end of the treatment analysis of the respective patient groups.

[Successful combination treatment of giant bicameral fusiform partially thrombosed vertebral artery aneurysm at 12-year-old patient (practical case and literature review)]. / Uspeshnoe kombinirovannoe lechenie gigantskoi dvukhkamernoi fuziformnoi chastichno trombirovannoi anevrizmy pozvonochnoi arterii u patsienta 12 let (sluchai iz praktiki i obzor literatury).

Giant cerebral aneurysms are diagnosed more often in children than in adults. Treatment of giant aneurysms is carried out both by endovascular and microsurgical methods. Literature information on combination of microsurgical and endovascular operations of cerebral aneurysms at children is little. A clinical case of the combined treatment of a giant bicameral fusiform partially thrombosed aneurysm of the right vertebral artery at a 12-year-old patient and a literature review on this topic are presented. The patient underwent several complex neurosurgical interventions during two operations: 1) microsurgery including revascularization of the right posterior lower cerebellar artery, thrombectomy and trapping of the larger chamber of fusiform aneurysm of the right vertebral artery, and 2) endovascular, which consists in the installation of redirecting stent from the left vertebral artery to main artery. The uniqueness of the case which we presented lies in the fact that the tactics of stage combined treatment for a complex aneurysm at child was originally planned and successfully implemented. The treatment allowed to ensure a complete shutdown of aneurysm and to exclude postoperative cerebral complications.

[Microsurgical treatment of aneurysms of vertebral and posterior-lower cerebellar arteries: surgical approaches, exclusion options, treatment results]. / Mikrokhirurgicheskoe lechenie anevrizm pozvonochnykh i zadnikh nizhnikh mozzhechkovykh arterii: khirurgicheskie dostupy, varianty vykliucheniia, rezul'taty lecheniia.

Aneurysms of vertebral (VA) and posterior inferior cerebellar arteries (PICA) are relatively rare pathologies and account for 3.4% of the total number of intracranial aneurysms. MATERIAL AND METHODS: The experience of microsurgical treatment of 67 patients with VA and PICA aneurysms in N.N. Burdenko National Medical Research Center for Neurosurgery of the RF Ministry of Health from 2012 to 2017 is presented. RESULTS: Most patients underwent reconstructive microsurgical interventions: clipping of the aneurysm neck in 42 (62.7%) patients and complex clipping with the formation of arterial opening - in 10 (14.9%). Exclusion of the aneurysm together with the carrier artery (trapping, proximal clipping) was performed on 10 (14.9%) patients. In 5 (7.5%) patients, deconstruction of the carrier artery of the aneurysm was performed after creating local anastomoses. The radical exclusion of aneurysms in the studied group was 95.5%. Postoperative dysfunction of the caudal group of cranial nerves was detected in 11 (16.4%) patients. There were no lethal outcomes, or cases with vegetative status outcomes. CONCLUSION: Microsurgical intervention is an effective way to treat VA and PICA aneurysms, subject to the principles of patient selection based on existing treatment algorithms as well as adherence to an interdisciplinary approach.

[Intracisternal administration of verapamil for the prevention and treatment of vasospasm in patients after microsurgical treatment of cerebral aneurysms in the acute period of hemorrhage]. / Intratsisternal'noe vvedenie verapamila dlia profilaktiki i lecheniia vazospazma u bol'nykh posle mikrokhirurgicheskogo lecheniia anevrizm sosudov golovnogo mozga v ostrom periode krovoizliianiia.

The first results of intracisternal administration of verapamil for the prevention and treatment of cerebral vasospasm (CVS) in patients in the acute period of subarachnoid hemorrhage (SAH) after microsurgical clipping of cerebral aneurysms are presented. OBJECTIVE: Safety assessment of the method of prolonged intracisternal infusion (PII) of verapamil. MATERIAL AND METHODS: Over the period from May 2017 to December 2018, 42 patients were included in the study, who underwent clipping of aneurysm of the anterior segments of the Willis circle. Most patients (78.6%) were operated during the first 6 days after SAH. For each patient, a thin silicone catheter was installed, through which verapamil was infused. A prerequisite was the installation of external ventricular drainage and opening of the lamina terminalis. The daily dosage of verapamil varied from 25 to 50 mg of the drug diluted in 200-400 ml of isotonic sodium chloride solution. The indication for the use of the PII method was the presence of one of the following factors: a score on the Hunt-Hess scale from III to V, 3 or 4 points on the Fisher scale, confirmed angiographically by the CVS before the operation. RESULTS: The PII procedure was performed from 2 to 5 days. The average dose of verapamil was 143.5±41.2 mg additionally, in the presence of an angiographically confirmed CVS accompanied by clinical manifestations, 14 (33.4%) patients received intra-arterial injection of verapamil in several stages, with individual selection of the drug dose. The formation of new cerebral ischemic foci of vasospastic genesis was observed in only 1 (2.4%) patient. No infectious intracranial complications were noted. The average follow-up period was 297.6±156.1 days. Long-term treatment outcomes, assessed by a modified Rankin scale from 0 to 2 points, were observed in 83.3% of patients. There were no outcomes such as vegetative status and no deaths. The frequency of liquorodynamic disorders, as well as epileptic syndrome did not exceed that among patients with SAH according to the literature. CONCLUSION: The study has confirmed the safety of prolonged PII. The efficacy of the method, compared with other methods for CVS treatment requires further investigation. The first results look quite promising: the observation shows a low percentage of new foci of cerebral ischemia and the absence of deaths associated with it. In patients with severe CVS, the efficacy of the PII method is increased when combined with intra-arterial administration of verapamil.

[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.

[Technical features and complications of cranioplasty in patients after decompressive craniectomy in the acute period of subarachnoid hemorrhage]. / Tekhnicheskie osobennosti i oslozhneniia kranioplastiki u patsientov posle dekompressivnoi trepanatsii cherepa v ostrom periode subarakhnoidal'nogo krovoizliianiia.

Decompressive craniectomy is used for arresting hypertension-dislocation syndrome developing in seriuos patients in the acute period of subarachnoid hemorrhage. After stabilization of the patient's neurological and somatic status, cranioplasty is performed for protective, cosmetic, and therapeutic purposes. The most common surgery in these patients is skull repair using an autologous bone graft. Before cranioplasty, the patient's bone is preserved in two ways: cryopreservation or subcutaneous implantation to the anterior abdominal wall area. Recently, there have been numerous reports of early and delayed complications of cranioplasty with autologous bone grafts. The use of artificial grafts may reduce the risk of postoperative complications compared to an autologous bone graft. Previously, 'freely' or 'manually' simulated biopolymers were used. At present, they are rarely used for repair of extensive defects due to a poor cosmetic result. However, the advent of stereolithographic modeling and computer modeling of artificial grafts has improved the cosmetic result of this surgery. The purpose of this study is to assess the risk of postoperative complications of cranioplasty as well as to define the criteria for choosing a cranioplasty technique.

[Microsurgical treatment of non-bleeding cerebral arteriovenous malformations]. / Mikrokhirurgicheskoe lechenie nekrovotochivshikh arteriovenoznykh mal'formatsii golovnogo mozga.

Treatment of non-bleeding cerebral arteriovenous malformations (AVMs) causes a lot of controversy among neurosurgeons around the world. The most discussed issue is choosing the method and indications for a certain treatment option. Despite the accumulated data, including the results of randomized studies, there is no consensus on this issue among experts. The purpose of this review is to analyze current concepts of the management and reasonability of microsurgical treatment of non-bleeding cerebral AVMs based on the latest published studies.

[Principles of surgical treatment for patients with asymptomatic aneurysms and cerebral aneurysms in the cold period after spontaneous intracranial hemorrhages]. / Printsipy vybora metoda khirurgicheskogo lecheniia bol'nykh s bessimptomnymi anevrizmami i anevrizmami golovnogo mozga v kholodnom periode posle spontannykh vnutricherepnykh krovoizliianii.

Surgical treatment of patients with cerebral aneurysms still remains one of the most important issues of cerebrovascular neurosurgery, which is associated with both complexity of treatment and risks posed by the disease. The purpose of this publication is to discuss the recommendations and algorithms adopted at the Neurosurgical Institute for choosing surgical treatment of patients with single and multiple intracranial aneurysms based on the clinical course of disease and anatomical morphological classifications of aneurysms. The study was based on a large clinical material: we analyzed treatment outcomes in 1,621 patients (2009-2017); of these, 966 (59.5%) patients were operated on using microsurgical techniques, and 655 (40.4%) patients underwent endovascular surgery. Surgical treatment of patients with cerebral aneurysms has been performed in close cooperation between two vascular (microsurgical and endovasal) departments, using the latest technical innovations.

[Disturbances of the hemostatic system in patients with aneurysmal subarachnoid hemorrhage]. / Narusheniia sistemy gemostaza u patsientov s anevrizmaticheskim subarakhnoidal'nym krovoizliianiem.

Subarachnoid hemorrhages due to rupture of cerebral aneurysms are characterized by high mortality. More than 25% of patients who have survived the first hours after aneurysmal SAH (aSAH) develop delayed cerebral ischemia that is one of the main causes of disability. The mechanisms underlying delayed ischemia have not yet been fully understood. Previously, the development of vasospasm was believed to be the only cause for development of delayed ischemia. In recent years, there has been evidence that hemostatic system disorders typical of this category of patients are the cause of cerebral artery thrombosis, which is one of the main pathophysiological mechanisms for the development of delayed cerebral ischemia. This review presents an analysis of published papers on hemostasis disturbances in patients with aSAH, their pathophysiological mechanisms, and their role in the development of cerebral ischemia.