[Cervical spondylogenic myelopathy: diagnostics, treatment, prognosis].

The authors present a review of literature focusing on state-of-art of surgical management of cervical spondylogenic myelopathy (CSM). Pathophysiology of CSM, evaluation and differential diagnosis are also described. Special attention is given to the value of neurophysiological aspects in pre- and postoperative examination.

[Identification of highly specific electroencephalographic patterns in patients with neuroepithelial tumors of the III ventricle by algorithmic methods].

An algorithm was suggested for identifying highly specific electroencephalographic (EEG) patterns in neurooncologic patients. The algorithm provides selection of patients with their further classification into main and control groups based on the already existing database of EEG indicators; requests to it; generation of mono-indicator candidates for EEG-patterns on the basis of a 4-dipole table for selecting and verifying sensitive and specific EEG patterns and outlining the best ones. Our material included 368 patients with basal-diencephalic tumors. Algorithmic methods revealed new EEG patterns in patients with different anatomical and topographical variants of neuroepithelial tumors in the III ventricle. We think it reasonable to use the revealed syndromes to improve diagnosis and identify pathophysiological basis of clinical syndromes.

[Possibilities of wavelet-syncronization method for estimation of the spatial distribution of components of auditory evoked potentials in healthy subjects].

Event-related potentials (ERP) are informative indicators of higher nervous activity of healthy people and patients in pathological states. Traditionally, methods of ERP processing include peak-time characteristics, topographical mapping and localization of equivalent dipole sources. At the same time, estimation of ERP synchronization is complicated by a short duration of the process. The wavelet analysis makes it possible to overcome the disadvantages of the traditional Furrier analysis and to calculate characteristics of ERP synchronization, in particular, phase synchronization. A new approach to estimation of the auditory ERP in healthy persons is proposed in the article. The method is based on the analysis of phase wavelet-synchronization of ERP individual components under conditions of differentiation of different degrees of attention concentration in healthy persons.

[Compression cervical spine cord injury in patients with posterior cranial fossa tumors operated on in the sitting position: two cases with different outcomes].

The paper describes two cases of posterior cranial fossa pathology, operated on in the sitting position on the operating table. In one case, symptoms of cervical spine injury caused by undiagnosed preoperative cervical spine pathology emerged in a female patient in the early postoperative period. In the other case, cervical spine pathology was diagnosed before surgery and evoked potentials were monitored to prevent possible cervical spine injury in the sitting position during an operation.

[Planning of surgical approach to intracerebral tumors of the hemispheres using fMRI, neuronavigation, and electrophysiological monitoring].

The paper discusses pre- and intraoperative application of different guiding techniques (frameless neuronavigation, fMRI, electrophysiological monitoring). We performed comparative analysis of different combinations of these methods. 74 patients with intracerebral tumors involving eloquent areas (sensorimotor cortex in 56 and speech zones in 18) were operated. In 9 cases 'awake surgery' was applied. We found that frameless navigation combined with brain mapping allows to optimize planning of surgical approach and to decrease postoperative neurological deficit. Also in certain cases 'awake craniotomy' can be replaced by fMRI and neuronavigation.

[The use of stabilo-training with feedback in the rehabilitation of patients with posttraumatic Korsakov's syndrome].

The complex research, including clinical scales (FIM, Mayo-Portland) and data on stabilography and electroencephalography (EEG) studies, was conducted in 10 patients with posttraumatic Korsakov's syndrome (KS) before and after the rehabilitation course using stabilo-training (ST) with feedback (7-12 sessions). A control group consisted of 18 healthy people. In patients with KS, more severe cognitive (memory) disorders were noted before ST that was correlated with the maximal reduction of coherence in all frequency bands in frontal and parietal-occipital areas as well as in the long diagonal pairs between the left frontal and the right parietal-occipital areas which was most distinct for the alpha-band. A trend to the normalization of stabilography parameters and step-by step increasing of EEG coherence parameters, especially the alpha-band, was found after the rehabilitation ST course, which was accompanied with the KS regress. It increased initially in parietal-occipital-central areas of the right hemisphere with the following increase in central-frontal areas and then in frontal areas, mostly in the left hemisphere, that was in compliance with the tendency to the normalization of spatial-temporary EEG organization.

[Intraoperative identification of oculomotor, trochlear and abducent nerves in surgery of invasive cranioorbital tumors (new technique)].

BACKGROUND: Aim of the study was to evaluate effectiveness of intraoperative identification of oculomotor nerves (OMN) in resection of skull base tumors invading superior orbital fissure and cavernous sinus. MATERIALS AND METHODS: 69 patients with cranioorbital tumors operated in Burdenko Neurosurgical Institute (Moscow, Russia) since 2000 until 2005 were included in the study. They were divided into 2 groups: 19 patients treated with intraoperative identification of OMN and 50 patients in the control group. Craniorbital meningiomas were in the majority among all cases. Intraoperative identification of OMN was performed using coaxial electrode while muscular response was registered through electrodes inserted in m. levator palpebrae superioris, m. obliquus superior and m. rectus lateralis (for III, IV and VI cranial nerves, respectively). Identification of IMN trunci was repeated throughout the whole stage of tumor resection for their preservation. RESULTS: comparison of dynamics of oculomotor dysfunction in early postoperative period in patients of both groups demonstrated that intraoperative identification of OMN allowed to decrease the frequency of oculomotor deficit. The rates in main and control groups were: for III and IV nerves--37% and 68% (p < 0.05), for VI nerve--47% and 54% (p > 0.05), respectively. CONCLUSION: application of intraoperative identification of OMN allows to decrease the risk of oculomotor deterioration due to III and IV nerve dysfunction by 1.8 times. Technically the method is quite simple and not time-consuming procedure.

[Identification of the cochlear nerve in surgical removal of vestibular schwannomas].

Review of methods which allow intraoperative identifying and monitoring of cochlear and facial nerves in resection of vestibular schwannomas is presented. We describe a case of successful identification and functional preservation of facial and cochlear nerves in a patient with acoustic neuroma. Detailed description of neurophysiological and neurosurgical aspects of surgical technique intended to preserve auditory functions is given. According to some authors, application of intraoperative neurophysiological techniques in surgery of vestibular schwannomas allows to preserve not only anatomical but also functional integrity of neural structures as well.

[Motor responses in transcranial magnetic stimulation and somatosensory evoked potentials in patients with pain syndromes]. / Motornye otvety pri transkranial'noí magnitnoi stimuliatsii i somatosensornye vysvannye potentsialy u bol'nykh s bolevymi sindromami.

The main goal was to evaluate the motor and somatosensory systems by recording evoked motor responses (EMRs) during transcranial magnetic stimulation (TMS) and somatosensory evoked potentials (SEPs) in patients with neurogenic pain syndromes before and after implantation of the systems for chronic antipain epidural stimulation. Fifteen patients with neurogenic pain syndromes and a control group of 15 apparently healthy examinees were examined. The patients were found to have a significant reduction in the motor thresholds of EMRs during TMS and an increase in the amplitude of EMRs after implantations of the systems. There were no significant changes in the amplitude-time characteristics of short SEPs as compared to the healthy examinees and after implantation of the systems. Analysis of the amplitude-time characteristics of long SEPs in these patients revealed a significant increase in the amplitude of the component P250 as compared to the normal values and its decrease after implantation of the systems.

[The identification and functional tracking of the facial nerve during the removal of tumors of the cerebellopontine angle]. / Identifikatsiia i slezhenie za sostoianiem litsevogo nerva vo vremia udaleniia opukholei mostomozzhechkovogo ugla.

Intracranial identification by electrostimulation and monitoring of the status of the facial nerve was intraoperatively used in 21 patients with cerebellopontine angle tumors of varying histological structure. Monopolar and bipolar electrostimulation, as well as electromyography and mechanography for recording the function of the facial nerve were compared. During removal of cerebellopontine angle tumors, identification and monitoring of the function of the facial nerve provide anatomic retention of this nerve when the tumor is radically eliminated. This is of essential significance for acoustic neurinomas. A combination of monopolar and bipolar stimulation for identification of the facial nerve simplifies removal of these tumors. As compared with electromyography, mechanography of facial nerve function during these operations is a more convenient technique due to the simplicity and absence of false operation for electric interferences. The study provided the optimum procedure for intracranial stimulation to identify the facial nerve within the cerebellopontine angle.

[Neuromonitoring: its current status and developmental outlook]. / Neiromonitoring: sovremennoe sostoianie i perskeptivy razvitiia.

A comparative analysis of monitoring techniques in neurosurgery is presented. Different facets of indications and possibilities of different techniques of monitoring as well as appropriate ways of their application are considered. The promise of multimodal monitoring is justified. The requirements for the general neuromonitoring concept are discussed.

[Somatosensory evoked potentials in the assessment of cerebral ischemia in combined operations for intracranial aneurysms]. / Somatosensornye vyzvannye potentsialy v otsenke ishemii golovnogo mozga pri kombinirovannykh operatsiiakh vnutricherepnykh anevrizm.

Combined surgery of extra-intracranial anastomosis (EICA) and occlusion of the afferent vessel by means of a balloon catheter was made in 14 patients with giant aneurysms of the internal carotid (IC) and middle meningeal artery (MMA). MMA was excluded without previously creating EICA in another patient. The purpose of the study was to define the informative value of a somatosensory evoked potential (SSEP) as an intraoperative criteria for possible permanent occlusion of the major vessel. In 9 patients, IC or MMA occlusion was shown to cause neither intraoperative SSEP changes no postoperative neurological defect. After IC occlusion one case showed 25% reductions in the SSEP amplitude, which was not followed by neurological deterioration. In another patient with IC occlusion, 40% decreases in the cortical response amplitude resulted in moderate postoperative hemiparesis. In one patient with transient IC occlusion, 50% falls in the SSEP amplitude were accompanied by poor EICA function, which made permanent IC occlusion be avoided. However, postoperative neurological defect progression was detected in 3 patients without intraoperative SSEP changes. The findings suggest that SSEP may be used to determine whether IC and MMA can be excluded at surgery for aneurysms. However, no intraoperative SSEP changes does not predict the constancy of a patient's neurological status.

[Intraoprative identification and monitoring of motor structures of the brain stem]. / Intraoperatsionnaia identifikatsiia i monitoring sostoianiia dvigatel'nykh struktur stvola mozga.

The purpose of this work was to evaluate the method of identification of motor structures of the bottom of the IV ventricle in order to find the zone through which it is possible to safely approach the bulky formation and to assess the efficacy of subsequent monitoring of these structures for the prevention of their intraoperative injury. Fourteen patients with bulky tumors of the caudal portions of the brain stem aged 4 to 57 were examined. Motor structures of the brain stem (nerves VII or IX, X, and XII, depending on the site of injury) were identified by direct electrostimulation of the surface of the rhomboid fossa and recording of the motor functions by mechanography of EMG. The results indicate that intraoperative identification of motor structures followed by monitoring thereof is a useful instrument which helps reduce the surgical risk of injuring these structures during surgery on the brain stem.