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PubMed1998

Assessment of the effects of combination therapy with ciprofloxacin and fenbufen on the central nervous systems of healthy volunteers by quantitative electroencephalography.

The potential effects of concurrent administration of fenbufen and ciprofloxacin on central nervous system activity in healthy young subjects were investigated by electroencephalography (EEG). Visual analog scales (VAS) were used to assess subjective measures of concentration, vigilance, tension, and irritability. When ciprofloxacin was administered in combination with fenbufen, none of the EEG parameters or VAS ratings measured were significantly different from those measured when the drugs were administered alone.

Adult↗
PubMed2001

Requests for electroencephalography in a district general hospital: retrospective and prospective audit.

OBJECTIVES: To determine the number of inappropriate requests for electroencephalography (EEG) and whether guidelines on use could reduce this number. DESIGN: Audit with retrospective and prospective components. SETTING: EEG department in district general hospital and centre for neurology and neurosurgery. PARTICIPANTS: Retrospective: 368 at the general hospital and 143 patients at the neurology centre. Prospective: 241 patients undergoing EEG at the general hospital. INTERVENTIONS: Guidelines for EEG issued to users of service at the general hospital. OUTCOMES: Retrospective: differences in requesting practice, result in different clinical scenarios, relative roles of procedure, clinical acumen in establishing diagnosis, usefulness of procedure. Prospective: change of requesting practice, impact on use. RESULTS: There were considerable differences in requesting practice. Non-specialists seem to use EEG as a diagnostic tool, especially in patients with "funny turns," when it is much more likely to yield potentially misleading than clinically useful information. The overall proportion of procedures considered to influence management, to be justifiable, and to be inappropriate were 16% (59), 28.3% (104), and 55.7% (205), respectively. In the prospective study the total number of requests was significantly reduced (chi(2)=33.85, df=5, P<0.0001), mainly because of fewer requests in patients with non-specific "funny turns" (chi(2)=21.90, df=6, P=0.0013). There was a concomitant change in the usefulness of EEG (chi(2 )=26.99, df=2, P<0.0001). CONCLUSIONS: This original audit informed clinical practice and had potential benefits for patients, clinicians, and provision of service. Systematic replication of this project, possibly on a regional basis, could result in financial savings, which would allow development of accessible local neurophysiology services.

Electroencephalography↗
PubMed2006

Which electroencephalography (EEG) for epilepsy? The relative usefulness of different EEG protocols in patients with possible epilepsy.

BACKGROUND AND AIMS: Electroencephalography (EEG) is an essential investigative tool for use in young people with epilepsy. This study assesses the effects of different EEG protocols on the yield of EEG abnormalities in young people with possible new epilepsy. METHODS: 85 patients presenting to the unit underwent three EEGs with differing protocols: routine EEG (r-EEG), sleep-deprived EEG (SD-EEG), EEG carried out during drug-induced sleep (DI-EEG). The yield of EEG abnormalities was compared using each EEG protocol. RESULTS: 98 patients were recruited to the study. Of the 85 patients who completed the study, 33 (39%) showed no discernible abnormality on any of their EEG recordings. 36 patients (43%) showed generalised spike and wave during at least one EEG recording, whereas 15 (18%) had a focal discharge evident at some stage. SD-EEG had a sensitivity of 92% among these patients, whereas the sensitivity of DI-EEG and r-EEG was 58% and 44%, respectively. The difference between the yield from SD-EEG was significantly higher than that from other protocols (p < 0.001). Among the 15 patients showing focal discharges, SD-EEG provoked abnormalities in 11 (73%). r-EEG and DI-EEG each produced abnormalities in 40% and 27%, respectively. 7 patients (47%) had changes seen only after sleep deprivation. In 2 (13%), the only abnormalities were seen on r-EEG. In only 1 patient with focal discharges (7%) was the focal change noted solely after drug-induced sleep. These differences did not reach significance. CONCLUSION: EEG has an important role in the classification of epilepsies. SD-EEG is an easy and inexpensive way of increasing the yield of EEG abnormalities. Using this as the preferred protocol may help reduce the numbers of EEGs carried out in young patients presenting with epilepsy.

Adolescent↗
PubMed1978

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↗
PubMedDate not supplied

Determinants of quantitative spectral electroencephalography in early Alzheimer's disease: cognitive function, regional cerebral blood flow, and computed tomography.

Electroencephalography (EEG) bands may have different clinical or physiological correlates at initial diagnosis of Alzheimer's disease (AD). We studied 163 consecutive patients with probable (n = 105) and possible (n = 58) AD with measurements of cognitive function (CAMCOG), regional cerebral blood flow (rCBF) with single photon emission computed tomography using technetium-99m-labeled hexamethylpropylene amine oxime, and computed tomography (CT). Lower CAMCOG scores were significantly and most strongly associated with lower parieto-occipital and fronto-central alpha power. In a separate analysis of cognitive domains, disturbances in language, praxis, attention, and abstraction were also significantly and most consistently related to decrease in alpha power. Presence of cortical atrophy as measured on CT showed some statistically significant relations with EEG bands, but these associations were not consistent. Lower temporal and parietal rCBF were significantly related to lower parieto-occipital alpha activity. Presence of leukoaraiosis was significantly associated with lower beta values, but also with higher absolute theta and delta activity. The results suggest that alpha on EEG is most closely linked to cognitive function and rCBF, while beta and theta activity more likely reflect lower cortical or subcortical changes. Our study thus provides evidence that the EEG bands reflect differential pathophysiologic changes in AD.

Aged↗
PubMedDate not supplied

Evoked potentials and electroencephalography in stuttering.

The study was aimed at finding what factors in evoked potentials and EEG related to stuttering in subjects 6-25 years of age. Thirty-seven subjects who stuttered and 25 nonstuttering subjects, matched for age, sex and education, were evaluated employing visual evoked potentials, auditory evoked potentials, event-related potentials (P(300)), WISC-(IQ), and electroencephalography. A significant reduction of amplitude of P(100) of visual evoked potentials was found in stutterers with a significant prolongation of wave latencies I, III, V and interpeak latencies I-III and I-V in brainstem auditory evoked potentials. No significant abnormalities were recorded in P(200), N(200) and P(300) of event-related potentials in stutterers compared with the control group. The dominant EEG rhythm was slower in stutterers with a significant interhemispheric asymmetry compared with the control group. Fifty-four percent of the stutterers had pathological EEG. Epileptiform activities were recorded in 16.2% of stuttering subjects. Focal left temporal spike activity was recorded in 5.4% of stuttering subjects. The findings of this study point to a possible role of an organic etiopathogenesis of stuttering.

Adolescent↗
PubMed1998

Classification based on overnight simultaneous monitoring by electroencephalography and cystometry.

OBJECTIVES: To evaluate the features of the clinical findings in three types (types I, IIa, IIb) of enuresis, classified by overnight simultaneous monitoring by electroencephalography (EEG) and cystometry (CM). METHODS: We performed a test to evaluate bladder capacity, arousal response and the pattern of nighttime urination in sucklings and infants. RESULTS: As for the values of enuretic bladder capacity (EBC), the smallest were found in enuresis type IIb. As for arousal response, enuresis type I showed the best, while enuresis type IIa showed the worst response. With regard to the pattern of nighttime urination in sucklings and infants, all sucklings had a stable bladder in the sleep state and urinated in the pattern of type IIa. The arousal response to bladder distention indicating type I appeared at the age of about 2 or 3. CONCLUSIONS: The smallest EBC in patients with enuresis type IIb represented a bladder dysfunction in the sleep period. It was observed that patients with enuresis type I had the best arousal function while those with enuresis type IIa had the worst arousal function. All sucklings urinated unconsciously during sleep in the pattern of type IIa. The arousal response to bladder distention indicating type I, which was not observed below the age of 1 year, was thought to appear at the age of about 2 or 3 years. If this change has not appeared by the age of 3, bed-wetting might persist after the age of 5.

Child, Preschool↗
PubMed1998

Effects of systematic treatment based on overnight simultaneous monitoring of electroencephalography and cystometry.

OBJECTIVE: To clarify the effects of systematic treatment based on overnight simultaneous monitoring by electroencephalography (EEG) and cystometry (CM) on each type of enuresis. METHODS: For enuresis type I, the change in the awakening response during the conditioning treatment with a therapeutic machine was observed. For enuresis type IIa, the effect of imipramine on the EEG was observed. For enuresis type IIb, the effect of oxybutynin hydrochloride on the cystometrogram (CMG) was observed. RESULTS: Values, in which the awakening score on the second night was subtracted from the score on the last night, were significantly higher in the effective cases than in the unchanged cases. Out of the 3 patients in whom imipramine was effective, an awakening response on the EEG was observed in 2. Neither of the 2 unchanged cases showed an awakening response. Out of 4 patients in whom oxybutynin hydrochloride was effective, uninhibited contractions (UIC) on the CMG disappeared in 3. UIC stopped in neither of the 2 unchanged cases. CONCLUSIONS: Improvement of the awakening response plays an important role in the effectiveness of conditioning treatment with our therapeutic machine. The generation of awakening response is thought to be the most important result of imipramine directly concerned with its clinical effect on enuresis type IIa. The main result with oxybutynin hydrochloride in enuresis type IIb is thought to be related to its antispasmodic effect.

Adrenergic Uptake Inhibitors↗
PubMed2002

Effects of carbamazepine on dexamethasone suppression and sleep electroencephalography in borderline personality disorder.

The pathophysiology of borderline personality disorder (BPD) remains obscure, but there is mounting evidence of brain dysfunction without focal abnormality. The dexamethasone suppression test (DST) and sleep electroencephalography (sleep EEG) have been studied in BPD, but the findings seem to be related to a concomitant axis I diagnosis of major depression (MD) rather than to BPD itself. There is no effective treatment for BPD. Carbamazepine (CBZ) has shown contradictory results and in a previous study, our results were negative. In this study, we investigated the effects of CBZ versus placebo on the DST and sleep EEG in a sample of 20 BPD patients without concomitant MD. CBZ given at doses that are therapeutic for epilepsy and affective disorders may have an effect on the DST and sleep EEG in BPD. CBZ significantly increased the postdexamethasone plasma cortisol values. This did not parallel MD or an increase in the Hamilton depression rating scores. CBZ also increased slow wave sleep (SWS). The mechanisms by which CBZ increased postdexamethasone plasma cortisol levels and SWS in BPD are discussed.

Adult↗
PubMedDate not supplied

Electroencephalography as a diagnostic tool in dementia.

Clinical electroencephalography is a relatively simple and inexpensive diagnostic tool with a high sensitivity for diffuse organic encephalopathy of various aetiologies but with a rather low specificity for the type of diagnosis. The highest sensitivity is shown in DAT and Parkinson dementia, and in these conditions the degree of EEG abnormality is correlated with the disease severity. Quantification of EEG makes these correlations more reliable and provides a method for monitoring therapeutic effects. Dementias with predominantly frontal pathology show much less EEG abnormality, and in these conditions the EEG is often normal despite obvious clinical dementia. Also, alcohol dementias often show normal EEG patterns. At an early stage of clinical evaluation, EEG may be useful in the discrimination of organic dementia from pseudodementia, because EEG is usually normal in depression, confusion, agitation and other psychiatric conditions. In pseudodementia due to intoxication with sedatives the EEG is usually dominated by diffuse beta activity. At the stage of differential diagnosis of an organic brain disorder, EEG cannot reliably discriminate between encephalopathies secondary to hydrocephalus, AIDS, cerebrovascular disease, B12 deficiency and primary degenerative diseases such as DAT. More specific EEG patterns are seen in acute cerebrovascular lesions, metabolic encephalopathies, i.e. of hepatic origin, Creutzfeldt-Jakob disease, herpes encephalitis, and nonconvulsive status epilepticus as possible causes of a rapidly deteriorating mental and neurological condition. Repeated EEG recordings over time would add significantly to the diagnostic information. New techniques such as topographical brain mapping, analysis of the EEG during REM sleep, coherence analysis of the EEG activity, and the combination of quantified EEG techniques with evoked potentials and event-related potentials will presumably add to the sensitivity as well as the specificity of the electrophysiological methods in the diagnosis of dementia.

Aged↗
PubMedDate not supplied

Clinical diagnosis of frontal lobe dementia and Alzheimer's disease: relation to cerebral perfusion, brain atrophy and electroencephalography.

The regional cerebral blood flow, brain atrophy, white matter changes and neurophysiologic changes were evaluated in 28 patients with a clinical diagnosis of probable Alzheimer's disease (AD) and in 8 patients with a clinical diagnosis of frontal lobe dementia (FLD) using single photon emission computed tomography, magnetic resonance imaging and electroencephalography (EEG). We found that FLD patients had more severe frontal blood flow reduction and less severe parietal blood flow reduction compared to AD patients. Among patients with mild dementia the EEG changes were less severe in the FLD group. No significant differences were found in white matter changes or in regional atrophy.

Aged↗
PubMed1975

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↗
PubMed1992

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↗
PubMed1994

Electroencephalography improves the prediction of functional outcome in the acute stage of cerebral ischemia.

BACKGROUND AND PURPOSE: We studied the value of clinical and electroencephalographic assessment in patients with acute first-ever supratentorial ischemia in predicting functional outcome after 1 year. METHODS: In 55 consecutive patients admitted after a median interval of less than 24 hours, the degree of handicap was dichotomized as moderate (Rankin grade 1, 2, or 3) or severe (Rankin grade 4 or 5). Clinical deficits were categorized according to signs of a lacunar or a cortical syndrome. Without knowledge of clinical data, electroencephalograms (EEGs) were classified according to findings predicting good or poor prognosis. The outcome after 1 year was assessed as good (Rankin grade 3 or less) or poor (Rankin grade 4 or 5 or death from stroke) and was correlated to clinical data and to EEG findings in the acute stage. RESULTS: Thirty patients with a moderate handicap on admission all had a good outcome (predictive value [PV] of the initial handicap, 1.00; 95% confidence interval [CI], 0.88 to 1.00). Of the 25 patients with severe handicap on admission a poor outcome occurred in 13 (PV, 0.52; 95% CI, 0.31 to 0.72). If these patients with severe handicap at baseline were subdivided according to clinical features, a lacunar syndrome predicted good outcome in 4 of 5 patients (PV, 0.80; 95% CI, 0.28 to 1.00), but a cortical syndrome predicted poor outcome in only 12 of 20 patients (PV, 0.60; 95% CI, 0.36 to 0.81). Of the 20 patients with severe handicap and a cortical syndrome at baseline, an EEG with features predicting a good prognosis correctly predicted good outcome in 6 of 7 patients (PV, 0.86; 95% CI, 0.42 to 1.00). An EEG with features predicting poor prognosis correctly predicted poor outcome in 11 of 13 patients (PV, 0.85; 95% CI, 0.55 to 0.98). CONCLUSIONS: Electroencephalography improves the prediction of functional outcome in patients with a severe neurological deficit in the acute stage of cerebral ischemia. This may have implications for the design of future intervention trials in acute stroke.

Activities of Daily Living↗
PubMed1991

Quantitative electroencephalography: a report on the present state of computerized EEG techniques. American Psychiatric Association Task Force on Quantitative Electrophysiological Assessment.

The American Psychiatric Association established the Task Force on Quantitative Electrophysiological Assessment in May 1989 to consider several questions of interest to psychiatrists. From the inception of techniques for quantitative electroencephalography (qEEG), the possibility was raised that it would substantially assist in the diagnosis of brain disorders. However, controversy exists over the scientific basis for such approaches and the training necessary for interpretation of computerized records. The task force's charge was to report 1) the present state of scientific knowledge about qEEG, 2) the role of qEEG in clinical psychiatric practice at the present time, 3) the training necessary for the use of qEEG techniques, and 4) the possible future of the technique in the study of mental disorders. The task force concluded that qEEG is particularly useful for the detection of abnormalities in slow waves, which are a feature of delirium, dementia, intoxication, and other syndromes involving gross CNS dysfunction. The ability of qEEG to help in the diagnosis of other disorders, such as schizophrenia or depression, is not yet established. Clinical replications and sharing of normative and patient data bases are necessary for the advancement of this field. Proper use of this technique requires extensive training in a center experienced in its use. Standards for training and for using the technology in psychiatry are urgently needed. This report was approved by the Board of Trustees in December 1990.

Brain Diseases↗
PubMed2006

The value of quantitative electroencephalography in clinical psychiatry: a report by the Committee on Research of the American Neuropsychiatric Association.

The authors evaluate quantitative electroencephalography (qEEG) as a laboratory test in clinical psychiatry and describe specific techniques, including visual analysis, spectral analysis, univariate comparisons to normative healthy databases, multivariate comparisons to normative healthy and clinical databases, and advanced techniques that hold clinical promise. Controversial aspects of each technique are discussed, as are broader areas of criticism, such as commercial interests and standards of evidence. The published literature is selectively reviewed, and qEEG's applicability is assessed for disorders of childhood (learning and attentional disorders), dementia, mood disorders, anxiety, panic, obsessive-compulsive disorder, and schizophrenia. Emphasis is placed primarily on studies that use qEEG to aid in clinical diagnosis, and secondarily on studies that use qEEG to predict medication response or clinical course. Methodological problems are highlighted, the availability of large databases is discussed, and specific recommendations are made for further research and development. As a clinical laboratory test, qEEG's cautious use is recommended in attentional and learning disabilities of childhood, and in mood and dementing disorders of adulthood.

Cooperative Behavior↗
PubMed2002

Effect of fluconazole on the pharmacokinetics and pharmacodynamics of oral and rectal bromazepam: an application of electroencephalography as the pharmacodynamic method.

Quantitative analysis of electroencephalography (EEG) is used increasingly to evaluate the pharmacodynamics of benzodiazepines. The present study aimed to apply the EEG method as well as more traditional approaches to an interaction study of bromazepam and fluconazole. Twelve healthy male volunteers participated in a randomized, double-blind, four-way crossover study. The subjects received single oral or rectal doses of bromazepam (3 mg) after 4-day pretreatment of oral fluconazole (100 mg daily) or its placebo. Plasma bromazepam concentrations were measured before and 0.5, 1, 2, 3, 4, 6, 12, 22, 46, and 70 hours after bromazepam administration. Pharmacodynamic effects of bromazepam were assessed using self-rated drowsiness, continuous number addition test, and EEG. Fluconazole caused no significant changes in pharmacokinetics and pharmacodynamics of oral or rectal bromazepam. Rectal administration significantly increased AUC (1.7-fold, p < 0.0001) and Cmax (1.6-fold, p < 0.0001) of bromazepam. These changes following rectal dose may be due to avoidance of degradation occurring in the gastrointestinal tract. Rectal bromazepam also increased the area under the effect curves assessed by EEG (p < 0.05) and subjective drowsiness (p < 0.05). EEG effects were closely correlated with mean plasma bromazepam concentrations (r = 0.92, p < 0.001 for placebo; r = 0.89, p < 0.0001 for fluconazole). Thus, the EEG method provided pharmacodynamic data that clearly reflected the pharmacokinetics of bromazepam.

Administration, Oral↗
PubMed1993

Clinical electroencephalography in a psychiatric service.

An audit of the use of clinical electroencephalography in a psychiatric service was carried out by examining the referrals for an EEG from the service over one year (11% of all referrals), comparing them with matched patient controls, rating the EEGs blindly and estimating the clinical value of the investigation for each patient; 37% were abnormal, 19% anomalous and 44% normal. The following two clusters of symptoms and signs were associated with EEG referral--the patients with "organic" mental state phenomena and/or CNS signs; EEG usually abnormal and the patients with behavioural changes that raise the suspicion of an organic process but, taken alone, are not compelling evidence of such (for example, impulsive behaviour, acute and atypical psychoses, perceptual or behavioural phenomena of the type associated with temporal lobe epilepsy in the absence of frank complex partial seizures); EEG usually normal or anomalous. Ninety-two percent of EEGs were judged to be of clinical value; 53% positive and 39% negative. Eight percent of referrals made no contribution to the clinical evaluation.

Adult↗