[Endovascular treatment of aneurysms associated with cerebral arteriovenous malformations]. / Endovaskulyarnoe lechenie anevrizm, assotsiirovannykh s tserebral'nymi arteriovenoznymi mal'formatsiyami.

There are proximal, distal and intranidal AVM-associated aneurysms (G. Redekop, 1998). OBJECTIVE: To evaluate treatment outcomes in 120 patients with AVM-associated aneurysms. MATERIAL AND METHODS: We analyzed treatment outcomes in 639 patients with cerebral AVM who underwent 1992 endovascular procedures between 2010 and 2019. AVM-associated aneurysms were found in 120 (18.8%) cases: 81 (67.5%) patients with 69 proximal and 29 distal aneurysms, 33 (27.5%) AVMs with intranidal aneurysms and 6 (5%) aneurysms without hemodynamic connection with AVM. One hundred and one malformations (16.9%) out of 596 supratentorial AVMs and 19 (44.2%) out of 43 subtentorial AVMs were associated with aneurysms. RESULTS: Intracranial hemorrhage occurred in 349 (53.3%) out of 639 patients with AVM: 97 (80.8%) out of 120 patients with AVM-associated aneurysms and 252 (48.6%) out of 519 ones with AVM and no aneurysms. All 33 patients with intranidal aneurysms in the AVM structure and 18 (94.7%) out of 19 patients with AVM-associated aneurysms and AVM in posterior cranial fossa had intracranial hemorrhage. There were 98 aneurysms in 81 patients with AVM-associated aneurysms. Eighty-nine (90.8%) ones underwent endovascular treatment, 6 (6.1%) patients with proximal aneurysms required microsurgery. Three distal aneurysms were not repaired. Thirty-four aneurysms were embolized with spirals. Embolization with spirals and balloon assistance was performed for 41 aneurysms, spirals with stent-assistance - for 9 aneurysms (including 1 distal MCA aneurysm in hemorrhagic period). Implantation of a flow-diverting stent was performed for 5 aneurysms (1 distal and 4 proximal aneurysms). There were 8 (8.9%) complications after embolization of 89 AVM-associated aneurysms (5 thromboembolic and 3 hemorrhagic events). CONCLUSION: According to our data, intranidal aneurysms require exclusion of the parent AVM segment due to high risk of hemorrhage. Treatment of proximal AVM-associated aneurysms should be carried out prior to AVM embolization. Distal aneurysms do not regress after definitive AVM treatment and should be operated on after total AVM embolization.

[Endovascular treatment of extracranial dissecting aneurysms of cervical arteries]. / Vnutrisosudistoe lechenie ekstrakranial'nykh dissektsionnykh anevrizm brakhiotsefal'nykh arterii.

BACKGROUND: Dissecting aneurysms of extracranial cervical arteries are a rare vascular pathology. To date, there is no consensus on the choice of optimal surgical approach for these aneurysms. OBJECTIVE: To evaluate the effectiveness of endovascular treatment of various extracranial dissecting aneurysms. MATERIAL AND METHODS: There were 19 patients with 21 extracranial dissecting aneurysms for the period from January 1, 2013 to October 19, 2020. Clinical examination, ultrasound and neuroimaging data were considered to determine surgical intervention. RESULTS: Nineteen patients underwent 20 intravascular interventions: aneurysm embolization with detachable coils with stent-assistance (n=9), flow-diverting stent implantation (n=5), arterial reconstruction with a stent for carotid stenting (n=3), aneurysm embolization with balloon assistance (n=1), aneurysm embolization with detachable coils without assistance (n=2). There were no complications. All patients were discharged without neurological impairment after 1-5 days. Long-term results of control angiography were analyzed within 1-19 months in 12 patients. All aneurysms were completely occluded. Asymptomatic occlusion of flow-diverting stent together with aneurysm occurred in 1 patient with low compliance to antiplatelet therapy. Other 6 patients are scheduled for elective angiography. CONCLUSION: Extracranial dissecting aneurysms of cervical arteries require vigilance due to their rare occurrence and risk of severe complications. In our opinion, intravascular interventions are advisable for these patients as effective and safe procedures.

[The first experience of endovascular treatment of chronic subdural hematomas with non-adhesive embolization materials of various viscosities: Squid 12 and 18]. / Pervyi opyt endovaskulyarnogo lecheniya khronicheskikh subdural'nykh gematom neadgezivnymi emboliziruyushchimi materialami razlichnoi vyazkosti SQUID 12 i 18.

Chronic subdural hematomas (CSH) usually require surgical evacuation via a burr hole or craniotomy. Certain incidence of recurrent postoperative CSH is known. Middle meningeal artery (MMA) embolization has been described as an alternative surgery for new or recurrent CSH or as a preventive measure to reduce the risk of postoperative recurrence. The authors report successful MMA embolization with 2 non-adhesive embolic agents of various viscosities (SQUID 12 and SQUID 18, Balt USA, Irvine, CA, USA) for recurrent postoperative CSH in a 44-year-old woman.

[Unfavorable outcome of giant vertebral artery aneurysm. Clinical case and literature review]. / Neblagopriyatnyi iskhod techeniya gigantskoi anevrizmy pozvonochnoi arterii. Klinicheskoe nablyudenie i obzor literatury.

OBJECTIVE: To demonstrate the unfavorable natural course and prognosis of giant vertebral artery aneurysm, to analyze the literature, and to conduct a postmortem histopathological study of the features of this disease.

[Endovascular embolization of high-flow arteriovenous fistulae with non-adhesive agents in the structure of cerebral arteriovenous malformations on the background of adenosine-induced cardioplegia]. / Opyt endovaskulyarnoi embolizatsii vysokopotokovykh arteriovenoznykh fistul v strukture tserebral'nykh arteriovenoznykh mal'formatsii neadgezivnymi embolizatami na fone adenozin-indutsirovannoi kardioplegii.

OBJECTIVE: To analyze the initial results of endovascular embolization of cerebral arteriovenous malformations involving high-flow arteriovenous fistulae with non-adhesive agents on the background of cardioplegia. MATERIAL AND METHODS: There were 13 patients who underwent surgery in 2018. Embolization of AVM with non-adhesive agents (ONYX, SQUID) was performed on the background of temporary cardiac arrest achieved by bolus intravenous administration of adenosine triphosphate. CONCLUSION: Adenosine administration in endovascular treatment of AVM with non-adhesive agents is able to improve the safety of surgical intervention and ensure more qualitative embolization.

[Molecular mechanisms of growth and recurrence of cerebral arteriovenous malformations: part 2 (our own research)]. / Molekulyarnye mekhanizmy rosta i retsidivirovaniya tserebral'nykh arteriovenoznykh mal'formatsii. Chast' 2 (sobstvennye issledovaniya).

BACKGROUND: Cerebral arteriovenous malformations (AVM) are not static congenital formations. These structures can grow, recur, and even appear de novo after a "complete" cure. OBJECTIVE: To analyze the dynamics of angiogenic factors before and after embolization of cerebral AVMs. MATERIAL AND METHODS: The study enrolled 314 patients with AVM who underwent endovascular treatment at the Department of Brain Vessels Surgery of the Polenov Russian Research Neurosurgical Institute for the period from 2011 to 2017. The control group included 33 healthy volunteers. Their age was comparable to that in the main group. The levels of serum vascular endothelial growth factor (VEGF), angiopoietin-2 (ANG-2) and matrix metalloproteinase-9 (MMP-9) were measured before and in 24 hours after endovascular embolization using enzyme-linked immunosorbent assay (Personal Lab, «Adaltis¼, Italy). RESULTS: Increased levels of VEGF, MMP-9 and ANG-2 were observed in 48.4% of primary patients with AVM. No correlation of increased level of these factors with gender, age, co-morbidities, localization and structure of AVM was found. High level of VEGF and MMP-9 was typical for AVM Spetzler-Martin grade III, AVM with hemorrhagic course, drainage into the deep cerebral veins and with afferents from the external carotid artery. Total embolization of AVM led to normalization of all elevated angiogenesis factors. In contrast, partial embolization resulted augmentation of VEGF and MMP-9 levels. CONCLUSION: Normalization of all elevated growth factors after total embolization confirms the absence of potency for AVM recurrence. Identification of the factors predisposing to possible growth of AVM should be a justification for total resection of AVM. Persistent elevation of serum growth factors after total embolization in accordance with the angiographic criteria may be a sign of subtotal occlusion of AVM.

[Molecular mechanisms of growth and relapse of cerebral arteriovenous malformations]. / Molekuliarnye mekhanizmy rosta i retsidivirovaniia tserebral'nykh arteriovenoznykh mal'formatsii.

Cerebral AVMs are not static congenital formations, they may grow, recur, and even appear de novo after complete resection, embolization, or radiosurgery. The author analyzes modern literature on the molecular mechanisms of AVM growth. The AVM intranidal vessels are exposed to abnormally high blood flows, which leads to the activation of molecular pathways in endothelial cells, causing proliferation and remodeling of AVM vessels. The existence of cerebral AVM is determined by more than 860 genes, the most important among them are the genetic mutations (SNPs) of VEGF, TGF-ß, IL-6, MMP, ANG, ENG. The possible causes of AVM relapse after removal or total embolization are described, as well as the mechanisms of stimulation of angiogenesis after partial embolization: hemodynamic changes in AVM, aseptic inflammation in response to embolizate and the local regional hypoxia inside the AVM. In response to this, growth factors are expressed in the endothelium that further stimulate angiogenesis in AVM. Understanding the complex molecular biology of AVMs is critical to identifying and predicting their behavior, developing new treatments that improve the results of endovascular and surgical treatment.

[Surgical treatment of large and giant vertebrobasilar aneurysms manifested by brainstem compression symptoms]. / Khirurgicheskoe lechenie krupnykh i gigantskikh anevrizm vertebrobaziliarnogo basseina, proiavliaiushchikhsia simptomatikoi kompressii stvola golovnogo mozga.

The study aim was to analyze the results of surgical treatment of vertebrobasilar (VB) aneurysms manifested by brainstem compression symptoms. MATERIAL AND METHODS: The study included 8 patients operated on in the period between 2014 and 2017. All patients underwent intravascular intervention; two patients had open surgery at the second stage. RESULTS AND CONCLUSION: Intravascular intervention, both alone and in combination with open surgery, is effective treatment of VB aneurysms whose clinical picture is manifested by brainstem compression symptoms. The use of flow-diverting stents in most cases has provided good radicalness in the long-term period, without worsening the functional outcome. Treatment of fusiform aneurysms of the basilar artery trunk requires separate consideration and an individual approach due to a high risk of thrombosis of short branches feeding the brainstem.

[Extrapontine myelinolysis developed after aneurysmal subarachnoid hemorrhage (a case report and literature review)]. / Ekstrapontinnyi mielinoliz, razvivshiisya posle anevrizmaticheskogo subarakhnoidal'nogo krovoizliyaniya (sluchai iz praktiki i obzor literatury).

TOPICALITY: Central pontine and extrapontine myelinolysis is a rare and dangerous form of the demyelinating process of undefined origin, the development of which is associated with a very low sodium level in the blood (hypernatremia). OBJECTIVE: To describe a rare case of extrapontine myelinolysis as a complication occurring in the hemorrhagic period of anterior communicating artery aneurysm rupture as well as to demonstrate that this condition can be diagnosed intravitally. CONCLUSION: Clinical vigilance of extrapontine myelinolysis may promote the timely diagnosis and treatment of this disease, which is a potential cause of death. Pulse-therapy with glucocorticoids provides the opportunity to achieve regression of neurological symptoms and to stabilize the patient's condition.