Clinical Neuroscience

[Physical and electrophysiological aspects of electroconvulsive therapy (review)]


DECEMBER 20, 2003

Clinical Neuroscience - 2003;56(11-12)

[Personnel and technical conditions for ECT (electroconvulsive therapy) is legally determined. In this article the author reviews studies focused on the technical questions of ECT. After the comparison of the unilateral and bilateral electrode placement an analysis is given on the physical properties of the stimulus used to elicit seizures. After discussing the questions of dose, vaweform frequency and polarity, the anatomical and physiological factors of impedance are evaluated. The author then discuss gender, age and encephalopathy as factors influencing seizure threshold. The connection between symmetry, regularity, and postictal suppression registered on the EEG and efficacy is observed. The EEG and EMG concordance is supposed to be connected also with the efficacy. In the discussion the author gives recommendations based on the literature.]



Further articles in this publication

Clinical Neuroscience

[The role of studies of Janos Szentagothai in developmental neurology]

KATONA Ferenc, BERÉNYI Marianne

[The vestibulospinal system plays determining role in the activation processes of elementary sensorymotor patterns characterised by the verticalisation of the trunk and elevation of the head. In the thirties of the last century János Szentágothai proved that axons of the vestibulospinal tract reach the cervical and thoracic spinal cord and innervate the muscles of the neck. Later he verified existence of various connections among the labyrinth, the vestibular system, and the motor nuclei of the III., IV. and the VI. cranial nerves. His studies explain the functional neuroanatomic background of sitting up, sitting and balancing in the air, head-elevation and head control during the execution of a special elementary sensorymotor pattern: ”sitting in air”. All these functions can be activated by labyrinthine stimulation long before the maturation of the corticospinal tract.]

Clinical Neuroscience

[Serotonin dysfunctions and the „Seven Deadly Sins”]

JANKA Zoltán

[The symbolic characters of the Seven Deadly Sins can be traced from time to time in the cultural history of human mankind, being directly specified in certain artistic products. Such are, among others, the painting entitled „The Seven Deadly Sins and the Four Last Things” by Hieronymus Bosch and the poems Divina Commedia and The Faerie Queene by Dante Alighieri and Edmund Spenser, respectively. However, there are several paragraphs referring to these behaviours of the Seven Deadly Sins in the Bible and in the dramas of William Shakespeare. The objective of the present review is to propose that dysfunctions in the central serotonergic system might be involved in the the neurobiology of these ’sinful’ behaviour patterns. Evidences indicate that behaviour traits such as Accidia (Sloth), Luxuria (Lust, Lechery), Superbia (Pride), Ira (Wrath, Anger), Invidia (Envy), Avaritia (Greed, Avarice), and Gula (Gluttony) can relate to the functional alterations of serotonin in the brain. Results of biochemical and molecular genetic (polymorphism) studies on the human serotonergic system (receptor, transporter, enzyme), findings of functional imaging techniques, effects of depletion (or supplementation) of the serotonin precursor tryptophan, data of challenge probe investigations directed to testing central serotonergic functions, alterations in the peripheral serotonin measures (platelet), and the changes in the CSF 5-hydroxy-indoleacetic acid content indicate such serotonergic involvement. Furthermore, results of animal experiments on behaviour change (aggressive, dominant or submissive, appetite, alcohol preference) attributed to serotonin status modification and the clinically evidenced therapeutic efficacy of pharmacological interventions, based on the modulation and perturbation of the serotonergic system (e.g. selective serotonin reuptake inhibitors), in treating the ’sinful’ behaviour forms and analogous pathological states reaching the severity of psychiatric disorders (depression, sexual disturbances, social phobia, impulsivity-aggression, obsessive-compulsive and related spectrum disorders, paranoid jealousy, eating disorders) all strongly suggest the possibility that brain serotonin dysfunctions might underlie the neurophysiology of the Seven Deadly Sins.]

Clinical Neuroscience

[Thallium poisoning induced polyneuropathy - clinical and electrophysiological data]


[Introduction - The aim of the study was the electrophysiological investigation of thallium induced polyneuropathy. Beyond the rarity of the illness, the motivation of this work was the possibility of following up the pattern of neuronal damage. Thallium is one of the most toxic heavy metal and its wide use increases the chance of chronic or accidental acute poisoning. The entero-hepatic circulation makes the accumulation of this toxic agent in tissues possible, mostly in neurons, in the epithelial cells of the digestive tract, in the germinative cells of the skin and testicles. In addition to alopecia and digestive complaints, the clinical picture of thallium poisoning is dominated by neurological signs. Severe axonal polyneuropathy develops in almost all cases, with further damage to the retina and impairment of cognitive functions being not unusual. The diagnosis is confirmed by finding high levels of thallium in body fluids, especially in saliva and urine. Case report - Electrophysiological examination of our accidentally poisoned patient revealed severe, sensory-motor, predominant motor axonal polyneuropathy and pointed out some aspects of the pattern of neurotoxic process: the initially distal lesion, the dying-back course and the capacity for regeneration. Conclusion - Because thallium has the same molecular targets as potassium ion thus impairing the energetical supply of the nerve cell, the most effective treatment is carefully loading with potassium. If recognized and treated early, thallium poisoning has a favourable prognosis.]

Clinical Neuroscience

[Predictors of lethal outcome in subdural haemorrhage]

SÁNDOR János, SZÜCS Mária, KISS István, EMBER István, CSEPREGI Gyula, FUTÓ Judit, VIMLÁTI László, PÁL József, BÜKI András, DÓCZI Tamás

[Background - Subdural haemorrhage (SDH) is of high public health importance because of its frequency, high case fatality ratio (CFR) and the young age of affected population. Despite the fact that the effectivity of guideline based treatment has been improved in the last decade, the Hungarian praxis shows variable compliance for recommendations. Objectives - The study aimed to describe the heterogeneity of the treatment effectivity (by geographically identifying the populations provided with appropriate or non-optimal level care), to determine the relationship between the institutional praxis quality and the results of treatment for SDH by linking the praxis properties to the patients' records. Methods - The institutions’ protocols were assessed by a self-completed questionnaire in 1997. The participating hospitals treated 79% of the Hungarian patients with SDH. The Hungarian hospital discharge data in 1997-1999 were the source of patient specific data. The risk factors of lethal outcome were investigated by logistic regression analysis. Results - High proportion of patients had been treated in hospitals with low compliance for guidelines. The non-permanent access to neurosurgical service and CT facility, the lack of intracranial pressure monitoring and the respiration support provided out of intensive care units worsened the survival of subjects. It was quantified that the full compliance could have diminished the case fatality ratio by 15-20%. The ratio of extreme county level CFRs exceeded 2.36 and extrapolating the effectivity observed in the county with lowest lethality, the Hungarian CFR would have been reduced by 21% among patients with SDH main diagnosis. (The interpretation of findings is limited by the lack of differentiation between acute and chronic cases and of direct categorisation of severity for subdural haemorrhage in the official hospital discharge records.) Discussion - The study results urge the increase of compliance for evidence based guidelines, since despite of some validity issues, it was demonstrated that the deviation from recommended practice is reflected in the disadvantageous outcome.]

Clinical Neuroscience

[Assessment of motor impairment with electromyography - the kinesiological EMG]


[Kinesiological electromyography means the application of the surface EMG measurement technique during movement and locomotion. The authors investigated the motor impairments of the upper limb of patients with spastic hemiparesis. Surface EMG activity in musculus biceps brachii and musculus triceps brachii were recorded during voluntary elbow flexion and extension movements. In some cases even the raw EMG signals contain the accurate information but more often the recorded signals should further be processed to achieve more valuable data concerning muscle performance. The limitations of the technique underlines the importance of the several steps of the processing. The purpose of this study is to present a systematic description of the methods and the precise application of surface EMG. The authors give a comprehensive view of different processing methods and demonstrate the application areas of the kinesiological EMG.]

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Clinical Neuroscience

The yield of electroencephalography in syncope

NALBANTOGLU Mecbure, TAN Ozturk Ozlem

Introduction - Syncope is defined as a brief transient loss of consciousness due to cerebral hypoperfusion. Although the diagnosis of syncope is based on a thorough history and examination, electroencaphalography (EEG) is also an important investigational tool in the differential diagnosis in this group of patients. In this study we aimed to identify the diagnostic value of EEG in patients with syncope. Methods - We retrospectively examined EEG recordings of 288 patients with the diagnosis of syncope referred to the Cankiri State Hospital EEG laboratory, from January 2014 to January 2016. The EEG findings were classified into 6 groups as normal, epileptiform discharges (spike and sharp waves), generalized background slowing, focal slowing, hemispherical asymmetries, and low amplitude EEG tracing. The EEGs were separated according to gender and age. Results - Total of 288 patients were included in this study, 148 were females (51.4%) and 140 (48.6%) were males. Among all the EEG reports, 203 (70.5%) were normal, 8 of them (2.8%) showed generalized background slowing and 7 (2.4%) demonstrated focal slow waves. Epileptiform discharges occured among 13 patients (4.5%). Hemispherical asymmetries were detected in 10 patients (3.5%) and low amplitude EEG tracing in 47 patients (16.3%). There was no significant difference between age groups in EEG findings (p=0.3). Also no significant difference was detected in EEG results by gender (p=0.2). Discussion - Although the diagnosis of syncope, epilepsy and non-epileptic seizures is clinical diagnosis, EEG still remains additional method

Hungarian Radiology

[High resolution sonography for the examination of peripheral nerves]


[High-frequency sonography is an important method for the imaging of the peripheral nerves, even though it is rarely used. For the examination of superficially located nerves, currently available transducers with frequencies between 12-17 MHz offer a better axial resolution than even MRI. Sonography is superior to MRI especially for the examination of nerves of the upper extremity. Main indications for the sonography of the nerves are entrapment syndromes, traumatic injuries of the nerves, tumors, polyneuropathies and sonographically-guided interventions. The sensitivity of sonography and electrophysiology in the diagnosis of carpal tunnel syndrome and cubital tunnel syndrome are comparable. The combination of ultrasonography with electrophysiological studies increases the diagnostic yield in carpal and cubital tunnel syndromes. Sonography provides information for planning of peripheral nerve surgery and is helpful in evaluating postoperative complications. In selected cases, sonography can detect nerve lesions that require operative therapy earlier than electrophysiology. With technical enhancements, highfrequency ultrasonography is gaining increasing importance in the routine diagnostics of peripheral nerves lesions.]

Clinical Neuroscience

[New applications of conventional EEG analysis ]


[Neurophysiological research suggests that the so-called “standard” EEG analysis has been confronted with new diagnostic challenges. The findings mainly concern the occurrence, the neurophysiological and clinical significance of epileptiform EEG discharges in several neurological and psychiatric disorders. In addition to well-known interictal and ictal discharges, a growing number of recently recognized epileptiform phenomena have been described. The first reports suggested that they might be relevant for the comprehensive description of epileptic dysfunction and might contribute to diagnosis and treatment as well. However, considerable improvement of present-day “standard” EEG technique is necessary to give an appropriate answer to most challenges. Reliable registration and quantitative assessment of well-known epileptiform transients require extended electrode coverage of the head (high-density EEG) and long-term recordings including waking and sleep states to estimate frequency and dyna­mics of targeted activities. Computer-based automatic event detection is preferable to spare time and cost of the evaluation. The authors review recent progress concerning epidemiology, neurophysiology and clinical impact of well-known epileptiform transients and candidate epileptiform activities in neurological and psychiatric conditions. However, recent results need confirmation in large patient populations; therefore, research should not be restricted to a few central laboratories.]

Clinical Neuroscience

[LORETA (Low Resolution Electromagnetic Tomography): A three-dimensional EEG source localization method]


[The author presents a brief overview of the EEG source localization method LORETA (Low Resolution Electromagnetic Tomography) with special reference to the not widely discussed data.]

Clinical Neuroscience



[Our aim is to define optimal stimulation patterns for controlling lower limb movements of spinal cord injured patients. Here we report on a study about cycling movements of healthy subjects under regular conditions and spinal cord injured patients whose cycling movement was generated by functional electrical stimulation. The stimulation pattern required for coordinated activities of lower limb muscles of spinal cord injured patients was improved by using the observations what we gained from measuring and analyzing cycling movements of 42 young healthy subjects. Kinematical parameters (joint angles) and muscle activities (EMG) were recorded simultaneously by an ultrasound based movement analyzing system. We replaced the cycling program of the commercially available stimulator with a new one that we developed on the basis of the measured healthy cycling movements. We present that our new stimulation patterns provided a great increase in the performance of our spinal cord injured patients.]