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At least 19 recordsLinked to original sources

Quantitative electroencephalography. A new approach to the diagnosis of cerebral dysfunction in systemic lupus erythematosus.

OBJECTIVE: Neuropsychiatric manifestations are common in patients with systemic lupus erythematosus (SLE), but accurate diagnosis is often difficult. We conducted a prospective study to determine the utility of neurometric quantitative electroencephalography (QEEG) as an indicator of cerebral dysfunction in SLE patients. METHODS: Fifty-two SLE patients were divided into 4 groups based on the results of neuropsychiatric evaluations. These included patients with objective evidence of neuropsychiatric SLE (NPSLE), patients with neuropsychiatric symptoms, patients with no evidence of NPSLE, and patients with a prior history of NPSLE: All QEEG findings were compared with data in an age-regressed normative database and with findings in an independent sample of normal subjects. RESULTS: QEEG sensitivity was 87%, and specificity was 75%. QEEG results were abnormal in 74% of the SLE patients with neuropsychiatric symptoms and in 28% of the patients with no evidence of active NPSLE: QEEG profiles varied as a function of the severity and type of neuropsychiatric manifestation present. Within this patient population, QEEG was more sensitive than magnetic resonance imaging, computed tomography scanning, or conventional EEG. CONCLUSION: Neurometric QEEG may be a sensitive indicator of cerebral dysfunction in patients with NPSLE and can differentiate patients with diverse neuropsychiatric manifestations. When combined with a careful clinical history and evaluation, QEEG provides information that may be useful for the early detection of NPSLE and for serial evaluation of disease activity and treatment efficacy.

Adult

Ictal electroencephalography and heart rate as treatment criteria in electroconvulsive therapy: a systematic review of the literature.

BACKGROUND: Decades before the emergence of precision medicine, psychiatrists raised the question of whether specific seizure characteristics could help optimize electroconvulsive therapy (ECT), as relationships between some of these characteristics and better outcomes were found. From 1990 onward, researchers focused on electroencephalography (EEG) and cardiovascular markers, which were broadly adopted by guidelines worldwide. However, the prognostic value of these markers is still controversial. Here, we provide a systematic summary of the studies on this topic. METHODS: We conducted a literature review on the use of ictal EEG and heart rate as outcome predictors in ECT using the PubMed, EMBASE, Cochrane and PsycINFO databases. RESULTS: Thirty-seven studies addressing more than 100 quality markers fulfilled our inclusion criteria. Single EEG markers were assigned to five categories (postictal inhibition, amplitude, coherence, regularity, and seizure duration). Heart rate and composite markers were considered separately. In contrast to single EEG markers, heart rate and composite markers could be consistently linked to better outcomes in patients with depression. Only a few studies on schizophrenia could be retrieved. CONCLUSION: Multiparametric markers outperformed single markers. Furthermore, changes in heart rate during seizures were related to better outcomes. Although clinical assessment remains the cornerstone of treatment guidance decisions, EEG and cardiac monitoring could help prevent insufficient seizures during the period preceding clinical improvement. Evidence on schizophrenia remains limited. More randomized trials are needed to analyze the role of composite markers as prognostic tools.

Humans

Electroencephalography, evoked potentials and MRI brain scans in saturation divers. An epidemiological study.

One hundred and fifty-six air and saturation divers, mean age 33.6 (range 21-49) years, were examined. The control group consisted of 100 offshore workers and policemen with the health requirements to have a diving certificate, mean age 34.0 (range 22-48) years. The examination protocol included electroencephalography (EEG), visual evoked potentials (VEPs), brain-stem auditory evoked potentials (BAEPs) and magnetic resonance imaging (MRI) of the brain and brain-stem. Abnormal EEGs, with focal slow waves mostly in the temporal regions and sharp potentials, were found in 18% of the divers and in 5% of the controls (P = 0.003). Abnormal EEGs correlated significantly with the exposure to saturation diving (P = 0.0006) and the prevalence of decompression sickness (P = 0.0102). Alcohol consumption was negatively correlated with abnormal EEGs (P = 0.0006). Mean I-III BAEP latency was increased (P = 0.047) in the diver group. P100 VEP latency decreased with age (21-49 years). High signal intensity changes obtained by MRI were found in 33% of the divers and in 43% of the controls (P = 0.14). It is concluded that the nervous system of saturation divers is influenced by their occupation and that EEG is a useful method in the health examination of divers.

Adult

Diagnostic value of electroencephalography in arteriovenous malformations.

Arteriovenous malformations (AVM) are usually located superficially in the subcortical white matter, and seizures are one of the frequently seen presenting features of AVM. The diagnosis of AVM is confirmed with various neuroimaging techniques. The present study comprised six patients presenting with seizures and headaches, referred to the neurodiagnostic unit to rule out/confirm epilepsy. All patients showed epileptiform activity on electroencephalography (EEG). Further investigations, such as angiography supplemented with computed tomography (CT) showed AVM. EEG is usually not considered a valuable diagnostic tool in AVM, but our results support the finding that EEG is an extremely reliable investigative tool, and should be supplemented with angiography and CT scan for better localization of AVM.

Adult

Electroencephalography and bladder innervation.

Combined electroencephalography and cystometry provides the only method presently available to analyze central micturition reflex disturbances. When these techniques are used in sleep cystometry they provide a rational method to evaluate nocturnal enuresis.

Cerebral Cortex

Pharmaco-electroencephalography: the value of quantified EEG in psychopharmacology.

One of the first routine applications of quantitative EEG analysis was in the field of human psychopharmacology. As early as the 1960's, quantitative techniques, mainly period and amplitude integration analyses or analogue filtering, were successfully applied to EEG data with the aim of quantifying and objectifying changes induced by psychoactive medidation. Thus, step by step, a new research field, pharmacoelectroencephalography, was developed. Many other sophisticated new techniques have been described in great detail from the engineering viewpoint. However, due to the language barriers common between representatives of the various disciplines involved, it is still difficult to view them in context with the experimental design as a whole. Therefore, based on examples taken from our routine work, an attempt is made to give a balanced judgement on the value of such techniques in pharmaco-electroencephalography, and their contribution to the CNS pharmacology.

Arousal

Predictive value of pharmaco-electroencephalography in early human-pharmacological evaluations of psychoactive drugs. First example: savoxepine.

The present paper forms the first part of a contribution to a comprehensive critical evaluation of the use of pharmaco-electroencephalography (pharmaco-EEG) as an instrument in the evaluation of pharmacodynamic effects of psychoactive drugs in man and further prediction of therapeutic effects by utilizing partial effects in a clinical pharmacological model situation. The basic principles and the methodological approaches are described first, prior to discussing the possibilities and limitations of the pharmaco-EEG in postulating hypotheses about therapeutic efficacy of psychoactive drugs in man. The discussion rests upon the findings with three selected new psychoactive drugs (savoxepine, levoprotiline and maroxepine), presented in this (Part I) and subsequent (Part II and III) reports. In this report results obtained with savoxepine, a novel tetracyclic compound, are described. Convergent evidence for antipsychotic potential of this drug has emerged from preclinical and pharmaco-EEG studies, subsequently corroborated by the first open trials in patients suffering from acute episodes of schizophrenia. In the pharmaco-EEG study a single dose of 0.5 mg savoxepine was tested in 15 healthy subjects with comparison to chlorpromazine (75 mg) and placebo. The experimental design was a threefold cross-over uncompleted block design with three consecutive trial days one week apart. Pharmaco-EEG was recorded under a high situational level of vigilance before 3 h and 6 h after drug administration. The recording was performed by means of 12 electrodes placed in the frontal, central, parietal and occipital regions. EEG-maps were constructed after power spectral analysis of absolute power changes in predetermined frequency bands within the range 0.5 to 30.0 Hz. The findings indicated EEG effects of savoxepine similar to those of chlorpromazine. In the tested dosage, however, savoxepine showed higher potency, later maximum (6 h) of the effect and lower sedative potential. Clinical trials performed in two centres and in, altogether, 28 acutely psychotic patients indicated antipsychotic activity of the drug in a low range of doses (on average, 0.1 to 0.9 mg/d). Even though the antipsychotic efficacy of savoxepine remains to be confirmed in controlled studies, the results favour the hypothesis that pharmaco-EEG has a value in predicting the quality of action of a new drug in man. Results also favour the complementary use of pharmaco-EEG in human pharmacology testing in order to objectively assess central effects of drugs and rationally estimate the doses for therapeutic trials.

Antipsychotic Agents

Recording small sharp spikes with depth electroencephalography.

Two patients with intractable seizures and focal temporal sharp waves also had small sharp spikes as incidental findings in their scalp electroencephalograms. Depth electroencephalography verified the intracerebral origin of the small sharp spikes and differentiated them from the more significant epileptiform abnormalities.

Adolescent

Electroencephalography and computerised tomography in vascular and non-vascular dementia in old age.

Nine normal elderly subjects and 81 patients with dementia have been studied by computerised tomography (CT) and electroencephalography (EEG). There was a broad relationship between slowing of the basic frequency of the EEG and the severity of mental impairment. Localised slow-wave activity was found in 19% of those with non-vascular dementia and 72% of those with dementia of vascular origin. The mean size of the ventricles, as determined from CT scans, was larger in the vascular than in the non-vascular group. Within the vascular group it was larger in those without than in those with visible infarcts. There was no relationship in either group between ventricular size and dominant EEG frequency.

Aged

Electroencephalography in haemophilia and Christmas disease.

Electroencephalography has been performed in a series of patients with haemophilia and Christmas disease because of the suggestion by other authors of a high incidence of abnormality. In an adult population of haemophiliacs no difference was found in the incidence of abnormalities compared with the general hospital population.

Adolescent

Somatosensory evoked potentials sensitivity relative to electroencephalography for cerebral ischemia during carotid endarterectomy.

BACKGROUND AND PURPOSE: The relation between electroencephalographic pattern changes and cerebral ischemia during carotid endarterectomy under general anesthesia is well established. Pattern changes seen on somatosensory evoked potentials under the same conditions are reported to be more sensitive indicators of cerebral ischemia. We estimated the sensitivity and specificity of somatosensory evoked potentials relative to electroencephalography for detecting cerebral ischemia during carotid endarterectomy under general anesthesia. METHODS: We simultaneously monitored electroencephalographs and somatosensory evoked potentials in 53 carotid endarterectomies performed on 51 patients under general anesthesia, and we determined the extent to which somatosensory evoked potentials detected cerebral ischemia defined by electroencephalographic pattern changes at the time of carotid cross-clamp. RESULTS: Twenty-three of the 53 cases studied had electroencephalographic evidence of ischemia following carotid cross-clamp. Ten of these 23 cases had an increased somatosensory evoked potential latency of 0.1 msec or greater (sensitivity 0.43). One of these 23 patients had a decrease in somatosensory evoked potential amplitude of 50% or greater (sensitivity 0.04). Of the 30 subjects who had no electroencephalographic evidence of ischemia, 13 had either no change or a decrease in somatosensory evoked potential latency (specificity 0.45). None of these 30 cases had a significant decrease in somatosensory evoked potential amplitude (specificity 1.0). If somatosensory evoked potential latencies were a sensitive method for detecting cerebral ischemia (true sensitivity of 0.95 or higher), the probability of only 10 subjects having somatosensory evoked potential latency increases would be less than 0.001. Therefore, our observed sensitivity cannot be attributed to chance. CONCLUSIONS: We conclude that measuring somatosensory evoked potentials is not a sensitive method for detecting cerebral ischemia during carotid endarterectomy.

Adult

Leukocyte migration inhibition by a brain tissue antigen and electroencephalography in uncomplicated measles.

In 11 patients with uncomplicated measles and in 10 control patients with acute enteritis, electroencephalography and leukocyte migration inhibition test using basic myelin protein as antigen were carried out. There were no EEG abnormalities and no migration inhibition in the control group. Leukocyte migration inhibition was observed in 9 measles patients; among these 5 had slight or moderate EEG abnormalities. It is suggested that EEG abnormalities have the same pathological background in uncomplicated measles as in measles encephalitis.

Antibody Formation

[Possibilities for the use of a wirelsss telemetric technic in electroencephalography].

Telemetry is the transmission of the test data of moving object, with a distinction being made between wireless and wire-connected telemetry. The applicability of this technique is examined on the basis of experience gained, and data gathered from books and articles on the subject. Biotelemetry constitutes a new development in technology and methodology which, if critically applied in meeting the various challenges confronting the specialist, can render useful service in the field of electroencephalography.

Aerospace Medicine

Spectral analysis of electroencephalography data in athletes with low erythrocyte magnesium.

In a population of high level athletes (kayakists) we compared quantitative electroencephalography data in those with low erythrocyte (magnesium magnesium deficit) and those with normal magnesium (controls). Logistic regression showed that the relative power of the alpha frequency band in the occipital lead is the most discriminant (P < 0.05). There was a significant positive correlation between low erythrocyte magnesium and alpha relative power (P < 0.05). An alteration of magnesium homeostasis could explain the occurrence of magnesium deficiency in athletes.

Adult

Simultaneous use of rheoencephalography and electroencephalography for the monitoring of cerebral function.

Many of the changes in human performance under stress or in hazardous environments may be attributed, in part, to altered cerebral functions. These changes may take place in either the cerebral neurologic or cerebral circulatory systems. Investigation of the interaction between intracranial blood flow and neural activity during these exposures would provide a better understanding of the human response to these conditions. Experimental and analytical procedures are described whereby the combination of rheoencephalography (REG) and electroencephalography (EEG) may provide additional information during the study of cerebral function. Examples are given to demonstrate the simultaneous use of these techniques during mental arithmetic and antiorthostatic bed rest. Results of these tests in both the time and frequency domains show that REG and EEG can be used to provide graded quantitative measures of cerebral responses to externally applied stressors.

Cerebrovascular Circulation

Electroencephalography.

Recent advances in electroencephalography (EEG) research are presented. Particular emphasis is placed on sleep and epilepsy research in humans. In this context, among others, studies on the modifications of EEG epileptic activity during sleep are discussed in more detail. A large number of reports come from EEG monitoring during presurgical evaluation and surgical treatment of drug-resistant epilepsy; information provided by these studies is therefore considered with special attention.

Brain

Effects of citicholine in subcortical dementia associated with Parkinson's disease assessed by quantified electroencephalography.

Two groups of patients with idiopathic Parkinson's disease underwent quantified electroencephalography (EEGq) using fast Fourier transfer to assess the effects of treatment with citicholine. Evidence of cortical cognitive impairment was seen in one group but not in the other. Certain parameters were established which enabled the two groups to be distinguished by examining specific EEGq indices. Specifically, differences were found in the overall potentials of the delta and alpha bands, in the alpha/theta index, in posterior activity, in the anteriorization index of the delta and alpha rhythms, and in the spatialization index of the alpha rhythm. The implications of these differences in the potential involvement of the frontal lobes in subcortical dementia in Parkinson's disease are discussed.

Aged

The experience with electroencephalography at the Kenyatta National Hospital, Nairobi.

Review of electroencephalography (EEG) requests at KNH over a 3 year period is presented. Majority of patients were aged between 0 and 10 years. None was older than 80 years. The epilepsies were the commonest reason for requesting EEG (58.5%). SSPE had the highest positivity rate of 91.7% followed by convulsive states of uncertain aetiology. The symptom of headache by itself was the least rewarding to study by EEG. It was more rewarding to first attempt to make a diagnosis of the headache. Hysteria had an EEG positivity rate of 40%, most of them being epilepsy. EEG picture for petit-mal, epilepsy focal seizure and generalized seizures are included in the text.

Adolescent