Clinical Neuroscience

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

GAZDAG Gábor

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.]

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

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[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.]

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[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.]

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