[microsurgery 'burr hole' for intracranial tumors and mesial temporal lobe epilepsy]. / Mikrokhirurgiia 'burr hole' pri intrakranial'nykh opukholiakh i medial'noi visochnoi épilepsii.

PURPOSE: In recent years, neurosurgery has been characterized by a clear tendency towards the development of minimally invasive and less traumatic surgical approaches. To minimize the degree of injury to the brain tissue, we have proposed burr hole-based microsurgical approaches. MATERIAL AND METHODS: In the period between February 2016 and February 2019, more than 500 microsurgical interventions were performed through a 14 mm burr hole using a technique that we called burr-hole microneurosurgery; to date, 200 of these have been analyzed. The age of patients varied from 16 to 79 years (median, 38 years). Female patients predominated - 1.6:1. Surgery for intracranial lesions with various locations was performed in 176 cases; in the remaining 24 cases, patients with hippocampal sclerosis underwent selective amygdalohippocampectomy. RESULTS: Various surgical approaches were used: transcortical approach in 81 (40.5%) cases; retro-sigmoid approach in 38 (19%); sub-temporal approach in 32 (16%); infratentorial supracerebellar approach in 25 (12.5%); interhemispheric approach in 17 (8.5%); telovelar approach in 5 (2.5%); trans-eyebrow approach in 2 cases. The resection degree was evaluated in 167 patients with planned maximum tumor resection. Resection was total and almost total in 145 (87%) patients, subtotal in 15 (9%), and partial in 7 (4%). The surgery duration varied from 35 to 300 min (mean, 80 min). The extubation time after surgery ranged from 5 min to 5 days (mean, 70 min). In 195 (97.5%) cases, patients were verticalized within the first 3 days after surgery. CONCLUSION: The proposed burr hole technique enables successful surgery in patients with various intracranial pathologies, using a smaller trepanation window compared to that in keyhole surgery. The proposed burr hole technique minimizes injury to the brain substance, significantly reduces patient's exposure to anesthesia, and decreases the entire duration of surgery.

[Orbital hemangiomas: capabilities of modern neuroradiological diagnostics]. / Gemangiomy orbity: vozmozhnosti sovremennoi neiroradiologicheskoi diagnostiki.

MATERIAL AND METHODS: In the period from 2010 to 2016. 14 patients with cavernous hemangioma (CH) and 2 patients with capillary hemangioma (CapH) of the orbit were examined. The age of CH patients varied from 17 to 67 years (median, 53 years); 8 females and 6 males. The age of CapH patients was 35 and 54 years. All patients underwent surgery with subsequent histological verification. CT-perfusion was performed in 10 CH patients and 2 CapH patients according to a developed low-dose protocol (80 kV, 200 mAs, tscan=40 s) with allowance for a target localizer (80 kV, 120 mAs) and at a maximum radiation dose of not more than 4.0 mZv. Neoplasm microcirculation was quantitatively assessed by calculating hemodynamic parameters: blood flow velocity (BFV), blood volume (BV), and mean transit time (MTT). MRI without and with contrast enhancement was performed in 11 CH patients and 2 CapH patients according to the ophthalmologic protocol (Signa GE, 3.0 T) accepted at the Institute: without contrast enhancement - T1, T2, and T2-FLAIR modes, T1 and T2 with a Fat Sat technique at a scan thickness of 3 mm, and DWI MRI; contrast enhancement - T1 (three projections) mode, including the Fat Sat technique. SWAN (n=2) and non-contrast MR perfusion ASL (n=3) were also used. Diffusion-weighted images (DWI) were processed with calculation of the apparent diffusion coefficient (ACD). RESULTS: In all CH patients, CT-perfusion revealed low perfusion parameters of blood flow: BVCH=0.86±0.37 mL/100 g, BFVCH= 4.89±2.01 mL/100 g/min with a high mean transit time MTTCH=10.13±3.05 s compared to the same parameters of blood flow in the normal white matter: CBVNormWM=1.63±2.22 mL/100 g, CBFVNormWM=9.72±3.13 mL/100 g/min, and MTTNormWM=6.76±2.78 s. In CapH cases, significantly increased blood flow velocity and volume values and a low MTT value in the tumor were observed: BVCapH=10.30±4.10 mL/100 g, BFVCapH=119.72±53.13 mL/100 g/min, and MTTCapH=4.35±1.79 s. In the case of orbital hemangiomas, optimal MRI modes were T1 and T2 with the Fat Sat technique, a scan thickness of 3 mm, and intravenous contrast enhancement. The revealed pattern of contrast agent accumulation by CH, initially in the central part and then in the periphery, may be a useful radiographic sign in the differential diagnosis with other orbital tumors. CONCLUSION: Modern CT- and MRI-based diagnostics of orbital hemangiomas provides not only the exact location, size, and spread of the lesion but also reveals the characteristic structural features of these tumors, and the use of perfusion techniques visualizes hemodynamics of the tumors. CT-perfusion-based hemodynamic parameters of cavernous hemangiomas typical of this type of hemangiomas may be used in the differential diagnosis with other tumors of this location. The use of contrast enhancement and the Fat Sat technique with a scan thickness of not more than 3 mm is optimal for MRI diagnostics of orbital hemangiomas.

[Neuroradiological diagnostics of atherosclerotic lesions and kinking of the carotid arteries in determination of indications to surgical treatment].

Range of methods for diagnostics of extracranial arterial stenosis includes both untrasonic techniques (transcranial Doppler study, duplex sonography, which are not only screening methods, but also used in surgery as well) and high-tech imaging methods--spiral CT scans and MR angiography with visualization of structural changes in vascular wall, quantitative and functional assessment of blood flow in vessels. Aim of this study was to determine the effective of non-invasive diagnostic techniques--MR angiography (MRA), including phase-contrast MRA (PCMRA), and spiral CT angiography (SCTA) in identification and comprehensive assessment of stenosis of internal carotid artery and comparison of capabilities of these methods with gold standard--direct angiography.

[Complex neuroradiological diagnosis in case of atherosclerotic lesion of the carotid arteries].

The diagnostic arsenal for extracranial stenosis includes both ultrasound techniques, such as transcranial Doppler and duplex sonography, which are not only screening methods, but also are used at surgery, and high-tech neuroradiological techniques, such as spiral computed tomographic and magnetic resonance angiography, which can visualize structural changes in the vessel walls and qualitatively and functionally evaluate blood flow in the vascular bed. The purpose of this investigation was to determine the efficacy of non-invasive diagnostic methods, such as magnetic resonance angiography, including phase-contrast magnetic resonance angiography and spiral computed tomographic angiography, in the detection and comprehensive evaluation of stenoses and to compare the feasibilities of noninvasive procedures with the gold standard--selective angiography.