[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.

[Nasal schwannoma with skull base destruction in a child (a case report and literature review)]. / Nazal'naia shvannoma s destruktsiei osnovaniia cherepa u rebenka (sluchai iz praktiki i obzor literatury).

Schwannomas (neurinomas) are benign, encapsulated, and slow-growing neoplasms developing from any peripheral, cranial, or vegetative nerve that has the Schwann sheath. Schwannomas of the nasal cavity and paranasal sinuses in adults occur rarely, less than 4% of cases. The world literature lacks similar data for the pediatric age group because these tumors in children are unique and extremely rare. The most common clinical symptoms of sinonasal schwannoma are nasal breathing disorders, hyposmia or anosmia, and snoring at night. Other symptoms are associated with intranasal schwannoma invasion of neighboring organs and tissues and include exophthalmos, epiphora (lacrimation), headaches, and anesthesia in the facial area. In this article, we describe a rare case of diagnosis and successful surgical treatment of a child with intranasal schwannoma destructing the skull base.

[Endoscopic transnasal surgery for giant fibrous dysplasia of the skull base, spreading to the right orbital cavity and nasopharynx (a case report and literature review)]. / Endoskopicheskaya transnazal'naya khirurgiya gigantskoi fibroznoi displazii osnovaniya cherepa, rasprostranyayushcheisya v polost' pravoi orbity i nosoglotku (opisanie nablyudeniya i obzor literatury).

BACKGROUND: An extended endoscopic endonasal approach is increasingly used in surgical treatment of space-occupying skull base lesions. The international literature reports only 20 cases of surgical treatment for fibrous dysplasia (PD) of the skull base using the endoscopic endonasal approach. We present our experience with the endoscopic endonasal approach in surgical treatment for giant fibrous dysplasia of the skull base, spreading to the right orbital cavity and nasopharynx. CLINICAL CASE: A 26-year-old male patient presented with cranial pain, Vth nerve dysfunction on the right, right keratopathy. OD=0.2 (near acuity - 0.3), OS=1.0, OD - incomplete eyelid closure of 2 mm, conjunctival injection, mucous discharge, corneal opacity in the lower pole and paracentrally, OS - normal appearance. Severe right-sided exophthalmos (more than 15 mm), impaired nasal breathing on the right, nasal (hemorrhagic) discharge. Magnetic resonance imaging and spiral computed tomography scans revealed a bone density lesion located in the area of the orbit, nasal cavity, maxillary sinus on the right, and labyrinth of the ethmoid bone. The patient underwent endonasal endoscopic resection of the lesion. RESULTS: The lesion was resected totally, which was confirmed by control SCT. Right-sided exophthalmos partially regressed (on the right: exophthalmos of 8 mm; protrusion: OD=23 mm, OS=15 mm; the eyeball was displaced downward and outward). The visual and oculomotor functions did not change. The neurological status remained at the preoperative level. CONCLUSION: Fibrous dysplasia of the skull base is an extremely rare disease. Modern techniques expand the indications for surgery of giant tumors of the skull base using minimally invasive approaches, in particular the endoscopic endonasal approach.

[Rupture of a giant aneurysm of the accessory middle cerebral artery: a case report and a literature review]. / Razryv gigantskoi chastichno trombirovannoi anevrizmy dobavochnoi srednei mozgovoi arterii: sluchai iz praktiki i obzor literatury.

The accessory middle cerebral artery is a rare congenital vascular abnormality. The international literature has reported cases of accessory MCA aneurysms. In this article, we describe a case of rupture of a giant partially thrombosed aneurysm of the accessory MCA. This case is of great interest due to rarity of the pathology and associated diagnostic errors.

[Tactics of surgical treatment of patients with unruptured asymptomatic cerebral aneurysms]. / Taktika khirurgicheskogo lecheniya bol'nykh s nerazorvavshimisya bessimptomnymi anevrizmami tserebral'nykh sosudov.

AIM: To clarify the indications for surgical treatment and the principles for choosing a surgical technique for patients with unruptured asymptomatic aneurysms (UAAs) based on the results of direct and endovasal operations performed at the Burdenko Neurosurgical Institute and on the literature data. MATERIAL AND METHODS: The study included 694 UAA patients (481 females (69.3%) and 213 males (30.7%)) operated on at the Burdenko Neurosurgical Institute from 1997 to 2013. The patients' age ranged from 1 to 74 years (mean age, 48.3 years). Multiple aneurysms were in 126 (18.2%) patients. Anterior circle of Willis aneurysms were in 92.8% of cases. Among these, internal carotid artery (ICA) aneurysms (46.3%) and middle cerebral artery (MCA) aneurysms (30.8%) were predominant. Microsurgical and endovascular interventions on aneurysms were performed in 665 patients (95.8%). RESULTS: Complete aneurysm exclusion was achieved in 94.8% of cases. A pronounced neurological deficit developed in 8 (1.2%) patients, and a moderate neurological deficit developed in 62 (9.3%) patients. Postoperative mortality was 0.5%. CONCLUSION: Surgical treatment of UAAs is associated with low disability and mortality rates. All UAAs need to be operated on, especially in young and middle age patients, if surgery is technically possible, and there are no concomitant diseases contraindicating the intervention. The choice of an UAA exclusion technique is made based on the general principles of surgical treatment of cerebral aneurysms. At present, the method of choice is endovascular surgery for most cases of vertebrobasilar basin and ICA aneurysms and a microsurgical intervention for anterior cerebral artery and MCA aneurysms.

[The principles for choosing a surgical technique for patients with acute cerebral aneurysm rupture]. / Printsipy vybora metoda khirurgicheskogo lecheniya bol'nykh v ostrom periode razryva tserebral'nykh anevrizm.

The article describes the principles for choosing a surgical technique for patients with cerebral aneurysms in acute subarachnoid hemorrhage. The principles were developed based on the experience gained at the Burdenko Neurosurgical Institute. Microsurgical and endovascular treatment options are considered.

[Results of deconstructive endovascular surgery in treatment of large and giant intracranial aneurysms]. / Rezul'taty dekonstruktivnykh endovaskulyarnykh operatsii pri lechenii krupnykh i gigantskikh intrakranial'nykh anevrizm.

AIM: To clarify the indications for deconstructive endovascular surgery in patients with large and giant intracranial aneurysms and to evaluate short-term and long-term postoperative outcomes. MATERIAL AND METHODS: The study was based on a retrospective analysis of the treatment results in 50 patients with large (15-25 mm) and giant (more than 25 mm) intracranial aneurysms, aged from 18 to 75 years, who were treated at the Burdenko Neurosurgical Institute in 2002-2014. The patients underwent a balloon occlusion test (BOT) in various modifications before stationary occlusion of the carrier artery. For vascular occlusion, we used detachable latex balloon catheters (33 cases) and microcoils (17 cases). The condition of patients in the pre- and postoperative period was assessed by using the modified Rankin Scale. RESULTS: There were no deaths due to occlusion of the internal carotid artery (37 patients). Postoperative complications occurred in 5 patients. On the basis of BOT, revascularization surgery involving placement of an extra-intracranial microanastomosis (EICMA) was performed in 6 cases. In more 4 cases, EICMA was placed in the early postoperative period due to developing signs of ischemia. Two of 7 patients underwent occlusion of both vertebral arteries (VAs) in the vertebrobasilar basin, which led to fatal outcomes. One more patient died of aggravation of brainstem compression after VA occlusion. There was no worsening of neurological symptoms among survivors. There were no deaths and persistent neurological disorders upon occlusion of branches of the main cerebral arteries, starting with the first order arteries (6 patients). Thirty one patients (66%) were followed-up in the period from 1 to 104 months. There were no deaths associated with artery occlusion. Two patients experienced delayed ischemic disorders. CONCLUSION: Occlusion of the carrier artery should be performed in a carefully selected group of BOT-negative patients. This surgery can be indicated for aneurysms with a complicated configuration, the topographic and anatomical features of which exclude reconstructive surgery.

[Combined treatment of cerebral arteriovenous malformations. Experience of the Burdenko Neurosurgical Institute].

OBJECTIVE: Despite the achievements of recent years, cerebral AVMs continue to pose a challenge to treatment. The objective of this work was the development of recommendations for combined treatment of AVMs based on analysis of the available material and published data. MATERIAL AND METHODS: The study included 93 patients hospitalized at the Neurosurgical Institute for combined treatment of cerebral AVMs in 2010-2014. A group of combined surgery (removal of an AVM with preoperative embolization) consisted of 40 patients, and a group of combined radiotherapy (radiation after partial embolization or partial removal of an AVM) included 53 patients. 36 patients underwent radiosurgery, and 17 patients received stereotactic radiation therapy. Both groups were analyzed in terms of outcomes, complications, and follow-up results. RESULTS: In the group of combined surgery, according to the Glasgow outcome scale, good results (grade 4-5) were achieved in 35 (87.5%) patients at discharge and in 27 (90%) patients during follow-up. Treatment outcomes, surgery duration, and the amount of blood loss were not significantly different from those in the control group. Complete AVM obliteration was achieved in 29 (80.6%) patients 3 years after radiosurgery and in 8 (47%) patients after stereotactic radiotherapy. In discussion, these findings are compared to the published data, and recommendations for AVM treatment are suggested. CONCLUSION: The combined treatment of AVMs is effective management for patients with complex AVMs (Spetzler-Martin grade III-IV AVMs). Successful treatment of AVMs requires careful planning and teamwork of vascular and endovascular neurosurgeons, radiologists, and neurologists.

[Endovascular treatment of large and giant intracranial aneurysms using flow-diverting stents].

OBJECTIVE: The objective was to evaluate the efficacy of treatment of patients with large and giant cerebral arterial aneurysms using flow-diverting stents (FDSs). MATERIAL AND METHODS: The treatment outcomes of 210 patients with large and giant intracranial aneurysms were analyzed. The study included patients with both asymptomatic and symptomatic aneurysms (manifested by SAH or pseudotumorous course). The rate of giant aneurysms was 62.3%. RESULTS: The technical success rate was 96%. In the perioperative period, the rate of clinically significant complications was 2.8%; the postoperative mortality was 3.3%. In the long-term period, total thrombosis of the aneurysm was observed in the majority of cases (80%) in the period from 4 to 12 months. Complete regression of clinical symptoms was observed in 26% of the cases, partial regression in 35%, and deterioration in 6% (of them, 4.9% of the cases were clinically significant). The long-term mortality was 2.5%. CONCLUSION: FDS is a highly efficient device for remodeling of the arterial lumen at the level of large, giant and fusiform intracranial aneurysms that significantly reduces the number of deconstructive operations and decreases the risk of ischemic complications of endovascular treatment for this complex vascular pathology.

[Endovascular treatment of large and giant intracranial aneurysms using stent assistance].

OBJECTIVE: The study objective was to evaluate the efficacy of occlusions of large and giant intracranial aneurysms with microcoils using stent assistance (SA). MATERIAL AND METHODS: The study is based on analysis of treatment outcomes in 37 patients with large (15-25mm) and giant (more than 25mm) intracranial aneurysms, aged 18 to 72 years, who were hospitalized at the Burdenko Neurosurgical Institute in the period between 2004 and 2014. Selection of patients for endovascular treatment using SA was based on the anatomical parameters of the aneurysm and carrier vessel. The main determining factor was the index of the aneurysm body to neck size ratio. Occlusion of aneurysms was performed with microcoils of different configurations, including those with a biologically active coating. Self-expanding stents with both an open-cell and closed-cell design were used for SA. The results of intervention for large and giant aneurysms were evaluated using control angiography immediately after occlusion of the aneurysm. The condition of patients with unruptured aneurysms as well as with ruptured aneurysms in the "cold" period was evaluated using the modified Rankin scale. The condition of patients in the acute period of SAH was evaluated on the Hunt and Hess scale. RESULTS: The technical success (successful implantation of stents and coils with total or subtotal aneurysm occlusion) was 94.5%. The postoperative disability was 2.7%; mortality was 2.7%. 28 patients were followed up for the period of 5 to 84 months (the mean was 20 months.). In the long-term period, the total and subtotal occlusion rate, including the results of re-operations, amounted to 90%. Delayed disability was 10.7%, and mortality was 3.5%. CONCLUSION: Stent assistance enables achieving total or subtotal occlusion of large and giant aneurysms in 90% of cases. In certain clinical situations, it is an alternative to other existing methods.

[The outcomes of stereotactic radiotherapy in patients with cerebral arteriovenous malformations].

INTRODUCTION: Cerebral arteriovenous malformations (AVMs) are the congenital anomalies of development of cerebral vessels during the embryonic period. The conventional therapy for AVMs currently includes endovascular management, microneurosurgical resection, and stereotactic irradiation. MATERIAL AND METHODS: A total of 315 patients with brain AVMs were subjected to stereotactic radiotherapy in 2005-2011. 238 (76%) patients had previous subarachnoid hemorrhage (SAH) within different time (6 months to 5 years) before the therapy; 214 (68%) patients had headaches; 113 (36%) patients had focal neurological symptoms caused by localization; and 82 (26%) patients had seizures. Twenty-three patients were subjected to surgical resection of an intracerebral hematoma prior to radiotherapy and 119 (36%) patients received endovascular treatment including partial embolization of the stroma of AVM. 267 patients received single-fraction radiosurgical irradiation. In patients with large AVMs, we used the hypofractionation technique consisting in target irradiation with several (usually 2-7) fractions; the radiation dose per fraction exceeds 2 Gy. Forty-six patients were irradiated in the hypofractionation mode; two patients had a course of stereotactic radiotherapy in the standard fractionation mode. The marginal dose of radiosurgical irradiation was 13-30 Gy (the average dose was 24 Gy). The main group of patients (38 individuals) with large AVMs was treated using hypofractionation of 35 Gy per 5 fractions. RESULTS: Control angiography was carried out in 225 patients who had been followed up for at least 2 years after therapy showed that complete obliteration was achieved in 83% of cases. The rate of symptomatic radiation reactions was less than 10%. The higher risk of developing obliteration was observed for AVMs less than 2 cm3 in size at marginal doses more than 24 Gy. In the hypofractionation group consisting of 27 patients with complete follow-up data, obliteration was observed in 10 (37%) patients. The rate of symptomatic reactions was less than 35%. CONCLUSIONS: The radiosurgical method is a minimally invasive choice of treatment for patients with brain AVM, which allows one to achieve sufficiently high degree of obliteration with the minimum complication rate. The hypofractionation procedure is the method of choice for treating large AVMs. Stereotactic irradiation using the Novalis linear accelerator makes it possible to treat patients with AVMs of virtually any location and volume.