[Results of hypofractionated stereotactic radiotherapy for resected and intact large brain metastases]. / Rezul'taty stereotaksicheskoi radioterapii v rezhime gipofraktsionirovaniya krupnykh metastazov v golovnom mozge posle khirurgicheskoi rezektsii i v samostoyatel'nom variante lecheniya.

Post-resection or isolated hypofractionated stereotactic radiotherapy (HF-SRT) is a therapeutic option for large brain metastases (>2 cm, LBMs). OBJECTIVE: To compare the results of post-resection or isolated HF-SRT in patients with LBMs. MATERIAL AND METHODS: A prospective study included 115 patients with 129 intact LBMs and 133 patients with 149 resected LBMs who underwent HF-SRT. Median baseline focal size was 22.5 and 28 mm, median target volume - 8.3 and 23.7 cm3, respectively. RESULTS: Median follow-up was 13.9 months, median overall survival - 19.1 months. After 12 months, local recurrences developed in 17 and 31% of patients, respectively (p=0.0078). Local recurrence after 12 months developed in 23% of patients with residual tumor in postoperative cavity compared to 16% of patients after total resection (p=0.0073). After 12 months, incidence of leptomeningeal progression was 27 and 11%, respectively (p=0.033), incidence of symptomatic radiation-induced necrosis - 4 and 23%, respectively (p=0.0006). CONCLUSION: Post-resection HF-SRT demonstrated better local control and less severe symptomatic radiation-induced necrosis compared to patients with intact LBMs. Incidence of leptomeningeal progression is significantly higher after resection of LBMs.

[Stereotactic irradiation for optic nerve hemangioblastoma associated with Von Hippel-Lindau disease: a case report and literature review]. / Stereotaksicheskoe obluchenie gemangioblastomy zritel'nogo nerva, assotsiirovannogo s bolezn'yu fon Gippelya­Lindau: klinicheskii sluchai i obzor literatury.

Hemangioblastoma is a benign tumor of the central nervous system arising sporadically or as a component of Von Hippel-Lindau disease. Von Hippel-Lindau disease is a rare autosomal dominant hereditary syndrome with various phenotypes caused by VHL gene variants. To date, only about 40 cases of optic nerve hemangioblastoma have been described in the literature. Stereotactic irradiation may be effective for supratentorial hemangioblastomas including lesions of optic nerves. The authors describe a rare case of stereotactic irradiation of intraorbital hemangioblastoma of the optic nerve in a patient with Von Hippel-Lindau disease.

Long-Term Results of the First Clinical Application of Stereotactic Radioablation Using a Linear Electron Accelerator for the Treatment of Ventricular Tachycardia.

We present the first clinical application of non-invasive stereotaxic radioablation of ventricular tachycardia (VT) refractory to medical and surgical treatment. Based on the results of invasive navigational activation mapping, a pericicatrical zone in the interventricular septum associated with VT was verified. Radiosurgical irradiation of the target in the region of the interventricular septum and the posterior apical segment of the left ventricle was performed on a TrueBeam linear electron accelerator (Varian) in accordance with the segmental scheme of the left ventricle. Irradiation doses for 95% of the internal target volume (ITV, 17 cm3) and planned target volume (PTV, 46 cm3) (31.2 and 25 Gy, respectively) were delivered by two full coplanar arches in 1 session. Irradiation was performed during expiration using a respiratory control system. The loading dose to critical structures was within tolerance. The planned follow-up period is 6 months. According to remote monitoring, the intensity of VT paroxysms over 48 days after treatment was from daily to 2-3 per day. Then, the incidence of VT paroxysms decreased (1-3 per week), and from the 64th to the 185th day (the end of the observation period), no VT paroxysms were recorded, which suggests that the impact was highly precise, conformal, and involved the total wall thickness. No undesirable effects and damage to adjacent organs were observed.

[Hypofractionated stereotactic irradiation for optic nerve glioma]. / Stereotaksicheskoe obluchenie gliom zritel'nogo nerva v rezhime gipofraktsionirovaniya.

Optic nerve glioma is a rather rare tumor. It predominantly arises in pediatric patients, including those with type I neurofibromatosis. This neoplasm is accompanied by decreased visual function and exophthalmos. Treatment strategy is individualized depending on age, volume and spread of tumor, as well as severity of clinical manifestations. Possible treatment options are surgical resection, chemotherapy, radiotherapy and their combination. Radiotherapy can be recommended for patients with intact visual functions, no severe proptosis and trophic lesions. Classic fractionation mode is used as a standard. Currently, the possibility of hypofractionated irradiation is being considered. OBJECTIVE: To evaluate safety and efficacy of hypofractionated radiotherapy in patients with optic nerve glioma. MATERIAL AND METHODS: Sixteen patients with optic nerve gliomas underwent hypofractionated stereotactic irradiation (CyberKnife) between May 2014 and October 2019. Single focal dose was 5.5 Gy. There were 5 fractions up to total focal dose of 27.5 Gy. The sample enrolled 14 children with a median age of 4 years (range 23 months - 13 years) and 2 adults aged 47 and 66 years, respectively. Median of tumor volume was 2.77 cm3 (range 1.69-10.01 cm3). RESULTS: Tumor growth control was achieved in all patients, partial remission was observed in 5 (32%) patients. None patient had deterioration of visual function. Improvement of visual acuity was noted in 3 (19%) cases. Visual field enlargement occurred in 4 (67%) out of 6 patients who were preoperatively examined. After irradiation, proptosis decreased by ≥ 1 mm in 9 (60%) out of 15 patients.

[Cell cultures in assessing radioresistance of glioblastomas]. / Ispol'zovanie kletochnykh kul'tur dlya otsenki radiorezistentnosti glioblastom.

To date, no modern methods of treatment allow overcoming malignant potential of glial neoplasms and significant increase of survival. Analysis of glioblastoma radioresistance using cancer cell cultures is one of the perspective directions, as radiotherapy is standard and available treatment method for these neoplasms. This review summarizes current studies identifying many factors of radioresistance of glial tumors, such as hypoxia, microenvironment and metabolic features of tumor, stem cells, internal heterogeneity of tumor, microRNA, features of cell cycle, DNA damage and reparation. We obtained data on involvement of various molecular pathways in development of radioresistance such as MEK/ERK, c-MYC, PI3K/Akt, PTEN, Wnt, JAK/STAT, Notch, etc. Changes in activity of RAD51 APC, FZD1, LEF1, TCF4, WISP1, p53 and many others are determined in radioresistant cells. Further study of radioresistance pathways will allow development of specific target aptamers and inhibitors.

[Radiosurgery for recurrent glioblastoma]. / Radiokhirurgicheskoe lechenie retsidivov glioblastom.

BACKGROUND: Despite the combined treatment in accordance with modern standards, recurrent glioblastoma usually occurs within several months after resection and causes low relapse-free and overall survival. One of the most effective methods for malignant glioma progression is repeated radiotherapy. Indications for this approach have expanded after introduction of stereotactic irradiation into routine clinical practice. OBJECTIVE: To evaluate the results of radiosurgery in patients with recurrent glioblastoma and to identify the factors determining its effectiveness. MATERIAL AND METHODS: Radiosurgery has been carried out in 168 patients with relapses of glioblastoma between 2005 and 2021. This study enrolled 88 patients with 180 foci of local and distant progression. Mean age of patients was 42.8±2.1 years (range 4-73). Mean period between diagnosis and repeated irradiation was 12.7 months. Mean volume of focus was 2.4 cm3, mean dose - 20 Gy. Median follow-up period after radiosurgery was 11.2 months. RESULTS: Repeated irradiation with correction of systemic therapy improved progression-free survival and overall survival with insignificant radiation-induced toxicity. Annual overall survival was 62.2%, median of overall survival after radiosurgery - 15.1 months. Significant factors of local control were marginal dose of at least 18 Gy and distant relapse. Median of progression-free survival in the group of distant progression of glioblastoma was only 3.6 months vs. 9.1 months in patients with local recurrence. CONCLUSION: Repeated irradiation in radiosurgery mode with a dose of 18 Gy and higher is an effective option for local treatment increasing progression-free and overall survival in patients with progression of glioblastoma.

[Changes in treatment paradigm for neurosurgical patients in the era of stereotactic irradiation. By the 15th anniversary of the Neuroradiosurgery in Russia]. / Izmenenie paradigmy lecheniya neirokhirurgicheskikh patsientov v epokhu stereotaksicheskogo oblucheniya. K 15-letiyu neiroradiokhirurgii v Rossii.

INTRODUCTION: Stereotactic method and new irradiation techniques ensured radiosurgical treatment with high precision and conformity and significantly expanded the indications for stereotactic irradiation in neurosurgery. MATERIAL AND METHODS: Over 15-year period, 29 976 patients underwent irradiation in various modes of fractionation on linear accelerators and Gamma Knife system at the first national radiosurgery center. RESULTS: Stereotactic radiotherapy and radiosurgery are followed by minimal number of complications and side reactions. At the same time, 5-year control of tumor growth for skull base meningioma was 96.8%, neuroma - 97%, glomus tumor - 94%, pituitary adenoma - 96-98%, craniopharyngioma - 95% in overall 10-year survival 86%, pilocytic astrocytoma - 97.5% in overall 5-year survival 99%. In intracranial metastases, median overall survival after radiosurgery was 10.1 months, 24- and 36-month overall survival - 25.9% and 19.2%, respectively. In patients with recurrent high-grade glioma, overall survival was 27.4 months. In case of metastatic spine lesions, control of tumor growth within 1 year was achieved in 90% of patients, pain relief - in more than 50% of cases. Obliteration of AVM and dural fistula was found in more than 80% of patients in years after treatment. Reduction or disappearance of pain was also observed in 80% of patients with trigeminal neuralgia. CONCLUSION: Stereotactic irradiation is effective and safe in patients with various pathologies of the central nervous system and characterized by high socio-economic indicators. Our own data indicate more significant role of stereotactic irradiation in the treatment of neurosurgical patients and make it possible to revise the existing treatment standards.

[Central neurocytomas: long-term treatment outcomes]. / Tsentral'nye neirotsitomy golovnogo mozga: otdalennye rezul'taty lecheniya.

Central neurocytoma is a rare benign brain tumor. These tumors may be giant and accompanied by compression of ventricular system and surrounding structures. Modern treatment of brain neurocytoma includes extended resection and restoration of normal CSF circulation. Surgical treatment does not often lead to total resection of these tumors. Redo resection was preferred in patients with tumor progression for a long time. In the last decade, various authors report stereotactic irradiation for continued tumor growth to ensure local growth control. This study was aimed at evaluation of postoperative outcomes in patients with brain neurocytomas, as well as treatment of tumor progression in long-term period. OBJECTIVE: To analyze recurrence-free survival in patients with brain neurocytomas, risk factors of recurrence-free survival, effectiveness of various treatments for tumor progression and delayed complications. MATERIAL AND METHODS: Long-term postoperative follow-up data of patients with brain neurocytomas are reported in the manuscript. We analyzed recurrence-free survival and risk factors of recurrence-free survival, treatment outcomes in patients with progression of brain neurocytomas, long-term complications and their prevention. RESULTS: Follow-up included 84 out of 115 patients with brain neurocytoma after surgical treatment in 2008-2017. Follow-up period ranged from 2 to 10 years (mean 6 years) after resection. Most patients had regression of neurological symptoms after surgery. Continued tumor growth within 12-96 months after surgery occurred in 26 (30.19%) out of 84 patients (19 cases after partial resection and 7 cases after total resection according to MRI data). Two-year recurrence-free survival was 94%, 5-year survival - 83%. Risk factors of continued tumor growth were resection quality and Ki-67 index. Redo resection was performed in 7 cases. Eleven patients underwent stereotactic irradiation for tumor progression. Indications for stereotactic irradiation of central neurocytoma are MR data on continued growth of lateral ventricle tumor without signs of ICH and CSF flow impairment. There were no cases of hemorrhage inside the residual tumor and CSF flow impairment in early postoperative period after redo resection. In all cases (n=11), stereotactic irradiation (mean follow-up 2.5 years) ensured satisfactory control of tumor growth with reduction of the neoplasm in 4 cases and no tumor growth in 7 cases. CONCLUSION: Resection of central neurocytoma ensures long-term recurrence-free period. The main causes of tumor recurrence are partial resection and high proliferative activity (Ki-67 index over 5%). Redo resection is advisable for tumor progression followed by CSF flow impairment. In case of continued growth of neurocytoma without signs of intracranial hypertension, stereotactic irradiation with various fractionation modes ensures effective and safe control of tumor growth.

[Radiosurgical hypophysectomy in cancer pain treatment. Literature review and clinical case]. / Radiokhirurgicheskaya gipofizektomiya v lechenii farmakorezistentnoi onkologicheskoi boli. Obzor literatury i opisanie klinicheskogo sluchaya.

Cancer pain is one of the main problem in modern medicine. According European Society for Medical Oncology data, cancer pain prevalence is 64% among patient with terminal stage of disease and in 46% standard pain therapy was ineffective. Radiosurgical hypophysectomy is one of the important and perspective method in cancer pain treatment. This method could be offered patient with chronic disease. According literature review, endocrinology complications were very rare and occurred 10 months after therapy. Value of analgesic effect was 70-90%. In some trials, procedure was effective not only nociceptive, but also in neuropathic pain. More trials require for determination of indications and mechanism of action. The case of successful relief of resistant pain in patient with pancreatic cancer by means of radiosurgical hypophysectomy is described.

[Glioblastomas in patients with medulloblastomas after combined treatment]. / Vozniknovenie glioblastom u patsientov s medulloblastomami posle provedeniya kombinirovannogo lecheniya.

Medulloblastoma (MB) is the most common brain malignancy in children occurring in the posterior cranial fossa. This tumor is characterized by high risk of metastasis along the CSF pathways. Significant progress in research of this tumor and appropriate treatment is associated with determining the various molecular categories of primary medulloblastomas. This analysis includes certain factors of cytogenetic and transcriptional proliferation. Modern treatment approaches for patients older than 3 years include advanced resection, craniospinal irradiation with a boost on the postoperative bed followed by platinum-based chemotherapy. Conventional radiotherapy including craniospinal irradiation results a significant number of complications. Morbidity rate is increased throughout long-term follow-up. Secondary tumors including glioblastomas are under special attention since their occurrence is associated with a fatal outcome. This may partially explaine the fact that chemotherapy without repeated morphological verification doesn't always ensure tumor growth control in patients with recurrent medulloblastomas. The authors consider irradiation-induced glioblastomas secondary to primarily verified medulloblastomas in patients who had previously undergone craniospinal irradiation as a component of combined treatment after tumor resection. It was found that the incidence of this phenomenon is significant and made up about 10% among patients with recurrent medulloblastomas. This value is significantly higher compared to previous data. The authors analyzed patterns of occurrence of irradiation-induced glioblastomas depending on the molecular genetic group and clinical characteristics of patients after primary surgery. Treatment outcomes were estimated too. It was concluded that morphological verification is necessary if long-term recurrence is diagnosed after combined treatment of medulloblastoma.

[Multicystic transformation of the post-radiation necrosis zone of the brain. A case report and literature review]. / Mul'tikistoznaya transformatsiya zony postluchevogo nekroza golovnogo mozga. Klinicheskoe nablyudenie i obzor literatury.

Post-radiation cyst of the brain is a rare complication that often arises many years after irradiation for head and neck neoplasms. The majority of the articles devoted to this problem are small samples or case reports. Nevertheless, the overall number of these patients is steadily increasing. The feature of post-radiation cysts is gradual enlargement followed by general cerebral and focal symptoms and ineffectiveness of therapy. Some patients with clinically significant post-radiation cysts can require surgical treatment. Insertion of Ommaya reservoir may be preferred in these patients. In some cases, this method is ineffective and more complex surgeries may be required. The objectives of this report were to analyze literature data and describe the patient with multiple recurrent brain cysts after previous irradiation for frontotemporal skin melanoma. Twenty-seven publications were analyzed for the period from 1997 to 2018. According to the literature, the incidence of post-radiation cysts varies from 0.4% to 28%, timing of occurrence - from 2 months to 27 years. These values significantly depend on the underlying disease. We report a 27-year-old patient who admitted to the Burdenko Neurosurgery Center with focal and general cerebral symptoms after irradiation for skin melanoma of the right frontotemporal region. These symptoms were caused by cystic lesion of the right temporal and frontal lobes. Surgical treatment consisted in insertion of 2 Ommaya reservoirs. This approach ensured complete regression of the cyst in the right temporal lobe and mild decrease of the cyst in the right frontal lobe.

[Correct use of Kreatech DNA probes to detect MYC gene amplification in medulloblastomas by fluorescence in situ hybridization]. / Korrektnoe ispol'zovanie DNK-zondov Kreatech dlia vyiavleniia amplifikatsii gena MYC v medulloblastomakh metodom fliuorestsentnoi gibridizatsii in situ.

In most cases, oncogene amplification are prognostic and predictive markers for various tumors, therefore DNA probes are unable to reveal changes in the copy numbers should not be used to diagnose malignant tumors. OBJECTIVE: To comparatively analyze DNA probes from different manufacturers to detect MYC gene amplification in routine practice. MATERIAL AND METHODS: The study material was formalin-fixed paraffin-embedded medulloblastoma fragments from 4 patients, with discrepancies in the results in the detection of MYC gene amplification. RESULTS: MYC gene amplification was determined using DNA probes: Kreatech MYC (8q24)/SE 8, Vysis LSI MYC SO, Vysis CEP 8 (D8Z2) SG, and Zytolight SPEC MYC/CEN 8 Dual Color Probe. The use of the probes Kreatech TERC (3q26)/MYC (8q24)/SE7 Triple-Color probe failed to detect MYC gene amplification; this probe showed a balanced profile of chromosome 8. CONCLUSION: In routine practice, fluorescence in situ hybridization with the DNA probes Kreatech MYC (8q24)/SE 8, Vysis LSI MYC SO, Vysis CEP 8 (D8Z2) SG and Zytolight SPEC MYC/CEN 8 Dual Color Probe can be the method of choice for studying the copy number of the MYC gene. However, the authors strongly recommend that the Kreatech TERC (3q26)/MYC (8q24)/SE7 Triple-Color should not be used for this purpose. In addition, probes for fluorescence in situ hybridization must be necessarily tested in large reference laboratories dealing with one or another area of oncopathology.

[Efficacy and safety of neuroprotection in patients with primary open-angle glaucoma]. / Issledovanie éffektivnosti i bezopasnosti neiroprotektsii pri pervichnoi otkrytougol'noi glaukome.

Elevated intraocular pressure (IOP) is considered one of the main factors in the development and progression of primary open-angle glaucoma (POAG). The main schemes of drug treatment and cell protection from glaucomatous damage are aimed particularly at reducing IOP. However, it is possible for the disease to progress with normalized IOP. This determines the need to search for drugs that would affect other pathogenetic links of the progression of POAG. PURPOSE: To study the effect of 'Cytoflavin' drug on the stabilization of glaucomatous optic neuropathy in patients with POAG. MATERIAL AND METHODS: The study included 103 patients with initial or developed POAG. Patients were randomized into two groups using random numbers: the control group patients (n=50) receiving standard conservative treatment, and the main group (n=53), where patients received the combined drug with metabolic action 'Cytoflavin'. In addition to standard ophthalmological studies, all patients underwent biological, electrophysiological, perimetric, structural topographic, laboratory and sociological examinations before and after the treatment. RESULTS: By the end of the 3rd month of the treatment, the patients of the main group showed positive dynamics of the amplitude and phase characteristics of bioelectric activity of the retina, improvement in the total sensitivity of the retina for central field of view. Cytoflavin contributed to reducing the rate of progression of glaucoma according to optical coherence tomography: stabilization of the thickness of the nerve fiber layer, reduction of the rate of global and focal loss of retinal ganglion cells. In patients of the main group, by the end of the 3rd month, the severity of oxidative stress has significantly reduced and the antioxidant defense improved. On the background of stabilized glaucomatous process, a subjective improvement in general and psycho-emotional health, increased confidence in the success of the therapy and thus the improved the quality of life was observed in comorbid patients of the main group. CONCLUSION: Cytoflavin acts on the mechanisms that enhance the protection of the retina against the effects of reperfusion injury and oxidative stress, contributes to the metabolic adaptation of neurons and leads to a more favorable variant of POAG.

Kidney cancer with brain metastases. Prognostic factors and treatment outcome.

The aim of this study was to study the effectiveness of stereotactic radiosurgery by Gamma Knife in kidney cancer with brain metastases. There were analyzed results in 112 patients with such spread of the disease who received treatment in the Gamma Knife Center, Moscow. The median age of patients was 58 years (range, 33-77 years). Total number of metastatic lesions was 444, and the average number of brain metastases in one patient 4 (from 1 to 30). A single brain metastasis had 28 patients (25 %). Median of total volume of brain metastasis for each patient was 5. 9 cm3 (from 0. 1 to 29,1sm3). Mean marginal dose for metastatic lesion was 22 Gy (from 12 Gy to 26 Gy) and the average value of isodose, on which planning was performed - 64% (from 39% to 99%). The overall survival after radiosurgery was 37,7%, 16,4% and 9,3% for 12, 24 and 36 months, respectively, with a median overall survival of 9,1 months (95% CI = 7,1-11,8). New brain metastases after radiosurgical treatment occurred in 44 (54,3%) patients with a median of 10,1 months. (95% CI = 7-18). Local recurrences after radiosurgical treatment were detected in 19 (17%) patients with a median of 6,6 months (95% CI = 4,0-9,6). The Karnovsky index was >80. Local control was achieved in 96% of metastatic lesions in 87% of patients. Side effects of radiosurgical treatment occurred in 33. 8% of patients (6% radionecrosis and 23. 8% an increase of perifocal edema). Thus stereotactic radiosurgery by Gamma Knife is an effective treatment option for brain metastases in kidney cancer providing a high level of local control of metastatic lesions with minimal neurotoxicity. In a case of distant recurrence reuse of such treatment provides good local control and improves overall survival compared with other methods of treatment.

[Stereotactic radiotherapy for spinal meningiomas and neurinomas].

INTRODUCTION: Over the past decades, stereotactic conformal radiotherapy of intracranial meningiomas and schwannomas has been recognized as an effective and safe procedure. Due to the wide use of the CyberKnife system and the procedure of extracranial stereotactic radiotherapy and radiosurgery, the positive experience can be used to treat spinal tumors. This study assessed the effectiveness of stereotactic radiaotherapy of spinal meningiomas and neurinomas using the CyberKnife system. MATERIAL AND METHODS: 46 patients (34 females and 12 males) received treatment between November 2009 and December 2013 (65 tumor nodules). The median age of patients receiving radiotherapy was 49 years (range: 20 to 82 years). Twenty neoplasms were subjected to surgical treatment. In 11 patients, formation of the recurrent tumor foci following treatment was observed along with the systemic disease, neurofibromatosis. Six patients had multiple meningiomas. The median total dose of radiation therapy of neurinomas was 13.6 Gy (12.1-14.1 Gy) per fraction; up to 18.2 Gy (16.0-21.1 Gy) per three fractions; and up to 25.6 Gy (24.8-27.6 Gy) per five fractions. Higher doses were used for meningiomas: 15.9 Gy (14.1-16.2 Gy) per fraction; 20.9 Gy (19.5-21.1 Gy) per three fractions; and 27.5 Gy (25.0-29.9 Gy) per five fractions. The load to 0.15 cm3 of the spinal cord was no higher than the maximum permissible load of 12 Gy per fraction. The mean catamnestic follow-up was 18.1 (4-52) months: 21,1 (4-52) months for neurinomas and 18 (4-31) months for meningiomas. We have not observed complete tumor elimination (i.e., complete response to radiation therapy) in our series. Partial response was observed in 9 (13.8%) cases; stabilization was achieved in 54 (83.1%) cases; and tumor continued to grow in 2 (3.1%) cases. The patients' status was evaluated using the Frankel, the Karnofsky, and the VAS scales. CONCLUSIONS: Our findings clearly demonstrate the short-term benefits of using CyberKnife radiotherapy for benign spinal cord tumors. The catamnestic follow-up needs to be extended to elaborate recommendations for radiation. The progress in this therapy type will considerably improve the quality of medical care provided to this cohort of patients.

[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.

[Efficacy of vitamin mineral complex "Focus forte" in combined treatment of primary open-angle glaucoma and age-related macular degeneration].

The efficacy of Focus forte is proved in patients with primary open-angle glaucoma (POAG) and age-related macular degeneration (AMD) in terms of improvement of functional retinal activity, oxygenation, metabolism normalization as well as morphometric retinal and optic nerve indices. Principles of evidence based pharmacotherapy in this study allow advising Focus forte in the treatment of patients with POAG and AMD.

[Application of robotized radiosurgical system CyberKnife for the treatment of neurosurgical patients].

Robotized system for radiosurgery CyberKnife (Accuray Inc., USA) is the first device dedicated and optimized for advanced irradiation during 1-7 fractions (i.e. radiosurgery and hypofractionation). CyberKnife is characterized by elaborate guidance system, high precision of dose delivery, possibility of conformal dose distributions with high gradient of target borderline dose which is most important in proximity of critical structures. The first CyberKnife system in Russia was installed in Burdenko Neurosurgery Institute. The paper presents 2-year experience of treating patients using CyberKnife. From April 2009 till October 2011 896 patients were treated using CyberKnife. Mean age was 48 years. Overall number of sessions was 2626. Radiosurgical procedures were performed in 21.8% of patients. 91% of cases were treated for intracranial lesions. Limited follow-up period in all kinds of pathology demonstrated results consistent with standard fractionation or radiosurgery. The rates of observed complications were also comparable with accepted techniques. CyberKnife system plays significant role in everyday activity of department of radiation therapy. In careful and thorough selection of patients it allows efficient and high-quality treatment of patients with neurosurgical diseases.

[First experience of stereotactic radiation therapy for vestibular schwannoma using CyberKnife].

Currently stereotactic radiosurgery has become the treatment of choice in small vestibular schwannomas. This paper discusses our first experience of application of CyberKnife system for stereotactic irradiation of these tumors. From April 2009 till June 2011 we treated 62 patients (35 female and 27 male) with vestibular schwannomas. Stereotactic radiosurgery using CyberKnife system was performed in 33 patients. Mean tumor volume was 2 +/- 1.4 cm3. Hypofractionated treatment was used in 30 cases (31 tumor). Mean tumor volume reached was 7 +/- 6.2 cm3 (range - 0.5-31.3 cm3). In a case of a patient with NF2 simultaneous irradiation of bilateral tumors was performed. Most frequently we applied 3 fractions 6 Gy each (17 observations of 31, or 55%) and 5 fractions with mean dose 5 Cy (10 cases, or 32%). Follow-up period varied from 1 to 26 months (mean 9 +/- 4.5 months). By the end of this study (June 30, 2011) surgical resection was required in the only case of 47-years old male patient with cystic schwannoma of left vestibular nerve 5 months after radiation treatment, due to progressive growth of the cyst and increased brainstem compression. Tumor growth control was established in 97.5% of cases. Stabilization of auditory function was achieved in 77.5% of series. Effective hearing was preserved in 75% of patients. Facial nerve palsy after stereotactic radiation treatment was observed in 2 cases (3%). Incidence of trigeminal nerve dysfunction was significantly higher: sensation disturbances occurred in 6 (10%) patients: 3% after radiosurgery and 16.7% after hypofractionation. We did not obtain significant correlations between risk of cranial nerve complications and dosimetric or demographic factors. However we observed stable tendency: larger initial volume of the tumor and presence of trigeminal nerve dysfunction before treatment were poor prognostic factors for trigeminal neuropathy. Stereotactic irradiation using CyberKnife system is effective and sufficiently safe technique for management of vestibular schwannoma. The paper demonstrates high rates of tumor stabilization, hearing preservation and minimal incidence of complications associated with trigeminal or facial nerve.

[Early results of irradiation of intracranial meningiomas using CyberKnife].

Meningiomas are frequently diagnosed intracranial lesions which cannot be resected radically in the majority of cases. Traditional radiotherapeutical techniques allow control of tumor growth in such situations. CyberKnife system may be used for radiosurgery and in sight hypofractionation. During 27 months 231 patient with intracranial meningiomas of different localization was treated in department for radiation therapy of Burdenko Neurosurgical Institute using CyberKnife system (Accuray Inc., USA). Mean age was 53 years. 55% of patients underwent previous surgical treatment, and diagnosis of meningioma was histologically verified. In 231 patient 374 targets were irradiated. Mean volume of irradiation reached 15.8 cm3 (range - 0.73-108.5 cm3). In 89% of cases hypofractionated therapy was used, in 10.1% we performed radiosurgery. Catamnestic data were available in 80 patients. Mean follow-up period was 11.6 months (6-27 months). Control of tumor growth was established in 100% of cases with WHO grade I tumors, in 66.7% of WHO grade II tumors and 60% in WHO grade III tumors. Deterioration after radiation treatment was observed in 16% of cases of 75 with control of tumor growth. In 8 cases worsening was due to radiation-induced reactions verified by MRI studies. Radiosurgical and hypofractionated treatment of meningiomas using CyberKnife is actual and highly-effective technique. Further investigations are needed to determine optimal standards of hypofractionated radiotherapy of meningiomas.