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The review is devoted to modern methods of electrophysiologicalevaluation of median nerve damage in the carpal tunnel (theso-called carpal tunnel syndrome, CTS) which is the most frequentlydiagnosed form of compression neuropathy of the upperextremities. Specificity and sensitivity of different methods ofelectromyography (EMG) in diagnostics of the disease, as well asin determining subclinical patterns of nerve involvement andindications for optimal treatment choice are demonstrated.EMG criteria of the CTS severity are provided. A protocol ofEMG evaluation of patients suspected for CTS, based on mostsensitive methods, is presented. The need of comprehensiveelectrophysiological evaluation of patients with median nervelesions is shown, with special attention to exclusion of hereditaryneuropathy. Problems of differential and false-positive diagnosisof CTS are considered.

Carpal tunnel syndrome (CTS) is a clinical condition with sensoryand motor manifestations related to median nerve (MN)compression at the wrist level. The goal of this study was tocompare two diagnostics methods, electromyography (EMG)and ultrasound (US) examination, in establishing the mostreliable and precise diagnostic approach to CTS. We examined67 patients with clinical diagnosis of CTS and a control groupof 42 healthy volunteers. For EMG and US, sensitivity andspecificity parameters were calculated, and grading of theseverity of MN injury was assessed with these technologies.The sensitivity and specificity for EMG was 93% and 97%, andfor US, 85% and 73%, respectively. The severity grades of MNinjury defined by EMG and US did not correspond to eachother. According to our data, EMG has higher sensitivity comparedto US in the diagnosis of CTS. EMG also allows estimatingquantitatively the severity of MN injury, while USmethod shows predominantly some qualitative estimation ofMN injury in CTS.

Navigation transcranial magnetic stimulation of the brain(nTMS) NBS eXimia Nexstim new method based on thestimulation of neurons by an alternating magnetic field andrecording responses to stimulation with electromyography.Precise guidance of the stimulus to a particular area of the cerebralcortex the patient, repeat the stimulus, somatotopical mappingof motor areas are features of this method. These characteristicsare achieved by a special navigation system that comparespatients head with the anatomical MRI image and thelocation of stimulating magnetic coil. This review presents thecurrent possibilities of the navigation TMS method in the diagnosisand treatment of neurological diseases; our own localexperience with the system.

About 1520% of myasthenic patients are refractory to standardsteroid therapy. The present study was aimed at evaluation ofefficacy and analysis of the algorithm of use of a novel immunosuppressantof natural origin, cyclosporine A, in the treatment ofsevere refractory forms of myasthenia gravis. In this work, for thefirst time on a large group of myasthenic patients (51 patientswho became ill at 580 years of age), mechanisms of action ofcyclosporine (sandimmun orally 2.55 mg/kg) on main levels ofneuro-muscular junction were studied, and new confirmation ofselective immune-modulating activity of cyclosporine (withouttotal decrease of patients immune system) was presented. Highefficacy and good tolerability of the drug in different pathogenicsubtypes of myasthenia gravis were shown. Cyclosporin may berecommended in refractory steroid-dependent myasthenia, aswell as in cases of combination of myasthenia with thymoma,autoimmune disorders and immunodeficiency viral infections.

Transcranial magnetic stimulation (TMS) is method of brainneurons stimulation by alternating magnetic field and measuringmotor-evoked potentials (MEPs) with electromyography monitoring.Recently, some new technologies were introduced, basedon classical TMS, which allowed noninvasive brain mapping ofcortical motor areas. Navigation transcranial magnetic stimulation(nTMS, NBS eXimia Nexstim) is one of them. In this articlewe describe our experience of m. abductor pollicis brevismotor area mapping in 29 healthy volunteers. Basic parametersof TMS were measured: MEP amplitude (408.49216.36 uV),latency (22.380.97 ms), passive motor threshold(40.084.68% for the left hemisphere, 48.719.16% for theright hemisphere). Maps of cortical areas were builded.

We present results of clinical and electrophysological analysis of34 patients with recurrent facial neuropathy (rFN). Its frequency(10.9%) among all forms of facial neuropathies was determined,and clinical and EMG characteristics, as well as possiblerisk factors, were described. A separate group of familial rFN wasidentified, and these patients exhibited high percentage of subclinicalperipheral nerve involvement. Positive family history,presence of relapses and electroneurographic features allowed tosuspect hereditary neuropathy with liability to pressure palsy inthese patients. However, molecular analysis of the РМР22 genefailed to reveal a typical gene deletion. These results leave openthe question about etiology and pathophysiologic mechanismsof rFN and warrant further studies of genetic defect underlyinga familial form of rFN.

В отечественной литературе недостаточно внимания уделено анатомическим вариантам иннервации конечностей. Тем не менее практикующему неврологу и нейрофизиологу регулярно приходится сталкиваться с нетипичной клинико-нейрофизиологической картиной, выявляемой как случайно, так и при патологии. В настоящей статье представлена информация о наиболее часто встречающихся вариантах межневральных анастомозов длинных нервов рук и ног. Особое внимание уделено нейрофизиологической картине данных межневральных коммуникаций. Настороженность в отношении возможной атипичной невральной иннервации поможет сократить ошибки в интерпретации данных, получаемых в ходе электронейромиографического исследования, улучшит понимание клинической картины при повреждении периферических нервов, участвующих в образовании анастомоза.

In the article we present the results of the retrospective clinico-electrophysiological analysis of 182 patients suffering from the idiopathic neuropathy of the facial nerve (Bell`s palsy). The comparison of the most common electromyographical (ENMG) predictors of outcomes was made. It was demonstrated that the most sensitive method in the acutest period (less then 5 days) is the level of excitability of the nerve, in the acute period (less then 14 days) – estimation of M-answer amplitude loss, and from the 21st day – the presence of denervation in muscles. The most specific electromyographical approach to estimate the therapy efficiency is an analysis of the M-answer amplitude and latency. In conclusion, neurologists have the possibility to predict the outcome and to control the therapy efficiency in any period of the disease. The correlation dynamics ÈNMG sensitivity settings – NLN on different dates can be used to determine the volume of ÈNMG – the NLN study depending on the timing for the treatment of patients.

The paper presents the results of clinical and electromyographic studies in 182 patients with idiopathic facial neuropathy (BellXs palsy). The most commonly studied parameters of electroneuromyography (ENMG) were compared to determine a good or poor prognosis for recovery. The most sensitive parameters were shown to be nerve excitability threshold in the acutest period (up to 5 days), M-response amplitude fall ratio on the affected and intact sides and reversibility of impaired irritability in the acute period (on days 10 to 14), and muscle denervation changes starting on day 21. The most sensitive ENMG parameters for the evaluation of the efficiency of performed therapy were changes in M-response amplitude and latency. Thus, ENMG can estimate disease prognosis and monitor treatment efficiency.