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PubMed1999

Determination of timing of brain injury in preterm infants with periventricular leukomalacia with serial neonatal electroencephalography.

OBJECTIVE: The aim of this study was to determine the timing of brain injury in infants with periventricular leukomalacia (PVL) with serial electroencephalography (EEG) recordings during the neonatal period. PATIENTS AND METHODS: We evaluated 172 preterm infants having a gestational age <33 weeks and weighing <2000 g. Initial EEG was recorded within 72 hours of life and then recorded once every 1 to 4 weeks. Serial cranial ultrasonography was performed and cystic PVL was diagnosed when multiple cystic formations of >3 mm in diameter were observed. RESULTS: Of the 172 infants studied, 26 were diagnosed as having cystic PVL by ultrasonography. EEG abnormalities were observed in 25 of 26 infants with PVL, although EEG abnormalities were seen in 20 of 146 infants without PVL. The initial EEG recordings were normal in 7 infants, but EEG abnormalities were observed later in 6 of these infants. In these 6 infants, the timing of injury was presumed to be postpartum. Only acute stage abnormalities were observed on initial EEG recording in 14 infants, and the timing of injury was presumed to be just before or around birth. Chronic stage abnormalities were recognized already on initial EEG recordings in the other 5 infants, and the timing of injury was presumed to be some time before birth. CONCLUSIONS: Our study indicates that it may be possible to determine the timing of injury in infants with PVL by serial EEG recordings.

Cerebral Palsy↗

PubMed2003

Amplitude-integrated electroencephalography coupled with an early neurologic examination enhances prediction of term infants at risk for persistent encephalopathy.

OBJECTIVES: The objectives of this study were to determine, first, whether an early neurologic examination could predict a persistent abnormal neonatal neurologic state comparable to the amplitude-integrated electroencephalography (a-EEG) and, second, whether a combination of the 2 methods would further enhance early identification of high-risk infants. METHODS: Fifty term infants were enrolled prospectively when they had evidence of intrapartum distress, Apgar score <or=5 at 5 minutes, or cord arterial pH <or=7.00 and were admitted to intensive care. Each enrolled infant underwent an early neurologic examination using a modified Sarnat staging system (stages 2 and 3 were regarded as abnormal) and a blinded simultaneous a-EEG measurement. Predictive values were calculated for a short-term abnormal outcome defined as persistent moderate to severe encephalopathy beyond 5 days. RESULTS: An abnormal short-term outcome was present in 14 (28%) of 50 infants. The neurologic examination was performed at 5 +/- 3 hours after delivery. A short-term abnormal outcome occurred in 9 (53%) of 17 infants with initial stage 2 and in both infants with initial stage 3 encephalopathy. In addition, 13 infants manifested features of both stage 1s and 2 and post hoc were classified (S1-2). Three of the latter infants (23%) developed an abnormal short-term outcome. The a-EEG was abnormal in 15 (30%) infants, 11 (73%) of whom developed an abnormal outcome. An abnormal a-EEG was more specific (89% vs 78%), had a greater positive predictive value (73% vs 58%), and had similar sensitivity (79% vs 78%) and negative predictive value (90% vs 91%) when compared with an abnormal early neurologic examination. A combination of abnormalities had the highest specificity (94%) and positive predictive value (85%). CONCLUSION: The combination of the a-EEG and the neurologic examination shortly after birth enhances the ability to identify high-risk infants and limits the number of infants who would be falsely identified compared with either evaluation alone.

Apgar Score↗

PubMed2005

Sleep-wake cycling on amplitude-integrated electroencephalography in term newborns with hypoxic-ischemic encephalopathy.

OBJECTIVE: The objective of this amplitude-integrated electroencephalography (aEEG) study was to evaluate the influence of perinatal hypoxia-ischemia on sleep-wake cycling (SWC) in term newborns and assess whether characteristics of SWC are of predictive value for neurodevelopmental outcome. METHODS: From a consecutive series of newborns born during a 10-year period, the aEEG tracings of 171 term newborns with hypoxic-ischemic encephalopathy were assessed for the presence, time of onset, and quality of SWC. SWC patterns were categorized with regard to the background pattern on which they presented, as normal or abnormal SWC. RESULTS: SWC was seen in 95.4% of the surviving newborns and in 8.1% of those who died. The median time intervals from birth to onset of SWC were significantly different in newborns with hypoxic-ischemic encephalopathy grades I, II, and III (7, 33, and 62 hours, respectively). Newborns with seizure discharges developed SWC with a delay of 30.5 hours. Good outcome was associated with earlier onset of SWC and normal SWC pattern. The difference in the median Griffiths' developmental quotients in newborns who started SWC before/after 36 hours was 8.5 points. The good/poor neurodevelopmental outcome was predicted correctly by the onset of SWC before/after 36 hours in 82% of newborns. CONCLUSIONS: The presence, time of onset, and quality of SWC reflected the severity of the hypoxic-ischemic insult to which newborns were exposed. The time of onset of SWC has a predictive value for neurodevelopmental outcome.

Activity Cycles↗

PubMed2006

Role of electroencephalography in attention-deficit hyperactivity disorder.

Attention-deficit hyperactivity disorder (ADHD) is characterized by symptoms of inattention, hyperactivity and impulsivity, and affects 3-5% of school-aged children. Recommendations regarding the relative importance of electroencephalography (EEG) in ADHD are ambiguous. Most guidelines for ADHD diagnostics only recommend an EEG in cases with clinical suggestion of seizure disorders or degenerative conditions and not for routine use. Although in most cases of ADHD, an EEG is indeed unnecessary, without a routine EEG, some children with absences or rolandic spikes will not be identified and, therefore, will not be treated correctly. The EEGs of children with ADHD demonstrated increased theta activity and fewer alpha waves compared with controls. Research on event-related potentials is helpful in identifying underlying attentional deficits in ADHD. Future studies that combine EEG analysis with functional magnetic resonance imaging data, positron emission tomography studies or genetic research will help to improve our knowledge about the pathophysiology of ADHD and perhaps lead to a better, more individual treatment in well defined subgroups.

Attention Deficit Disorder with Hyperactivity↗

PubMed2000

[Quantitative electroencephalography in obsessive-compulsive disorder: preliminary results].

The predictive value of quantitative electroencephalography (EEGq) was investigated with regard to the pharmacological treatment of 10 non-medicated obsessive-compulsive disorder (OCD) patients diagnosed according to DSM-IV criteria. The following variables were selected: bipolar relative power in alpha band for Cz-C3, Cz-C4, T3-T5, T4-T6, T3-F7 and T4-F8; bipolar relative power in theta band for Cz-C3, Cz-C4, T3-T5, T4-T6, T3-F7 and T4-F8; and monopolar relative power in theta band for Fp1, Fp2, F7, F3, Fz, F4 and F8. There was statistically significant deviations in five patients with regard to bipolar relative power in alpha band for central regions when compared to normative data bank (control group). This group of patients had a significantly lower age of OCD onset and worse response to pharmacotherapy with serotonin reuptake inhibitors.

Adolescent↗

PubMed2004

Quantitative electroencephalography (qEEG) to discriminate primary degenerative dementia from major depressive disorder (depression).

Electroencephalography (EEG) can be a valuable technique to assess electrophysiological changes related to dementia. In patients suspected of having dementia, the EEG is often quite informative. The sensitivity of the EEG to detect correlates of psychiatric disorders has been enhanced by means of quantitative methods of analysis (quantitative EEG). Quantitative features are extracted from, at least, 2 minutes of artifact-free, eyes closed, resting EEG, log-transformed to obtain Gaussianity, age-regressed, and Z-transformed relative to population norms (Neurometrics database). Using a subset of quantitative EEG (qEEG) features, forward stepwise discriminant analyses are used to construct classifier functions. Along this vein, the main objective of this experiment is to distinguish profiles of qEEG, which differentiate depressive from demented patients (n = 125). The results showed that demented patients present deviations above the control group in variables associated to slow rhythms: Normed Monopolar Relative Power Theta for Cz and Normed Bipolar Relative Power Theta for Head. On the other hand, the deviation below the control group occurs with the variable associated to alpha rhythm: Normed Monopolar Relative Power Alpha for P3, in dementia. Using this method, the present investigation demonstrated high discriminant accuracy in separating Primary Degenerative Dementia from Major Depressive Disorder (Depression).

Aged↗

PubMed1994

Relationship of cerebral blood flow, cerebral metabolism, and electroencephalography to outcome in acute experimental compression ischemia--barbiturate effects on delayed brain swelling.

Acute compression ischemia was induced in 30 cats by progressive inflation of an epidural balloon, followed by rapid decompression. Changes in intracranial pressure, mean arterial blood pressure, cerebral blood flow (CBF), arteriovenous oxygen difference (AVDO2), cerebral metabolic rate of oxygen (CMRO2), and electroencephalography (EEG) were studied in 13 untreated animals and in seven animals receiving barbiturate. Ten cats with cardiovascular or respiratory problems, or intracranial hematoma were excluded from the study. In untreated animals, six (46%) survived with no brain swelling and were classified as the "no swelling group," and seven (56%) died from fatal brain swelling and were classified as the "delayed swelling group." All animals with barbiturate therapy showed no brain swelling. Serial measurement of CBF, AVDO2, and CMRO2 indicated the existence of postischemic delayed hypoperfusion associated with relative hypermetabolism in untreated animals. Good recovery of CBF and CMRO2 was observed in the "no swelling group," and poor recovery in the "delayed swelling group." The time course of the total fast-wave components on EEG was quite similar to that of CMRO2, and the time course of the "CBF index," which is % fast-wave component of EEG divided by AVDO2, was similar to that of CBF. Barbiturates reduced CMRO2 and fast-wave component during administration, possibly improving the relatively hypermetabolic state, and reduced the mortality rate to 0%. The maximum effects of barbiturate could be expected by administering the drug at the stage of delayed hypoperfusion with relative hypermetabolism, indicated by rapid recovery of the % fast-wave component, high AVDO2, and low CBF index.

Animals↗

PubMed2001

The topography of quantified electroencephalography in three syndromes of schizophrenia.

This study investigated the association between quantified electroencephalography (qEEG) and three psychopathological syndromes, derived by a factor analysis of the symptom profile of a group of 40 subjects diagnosed with schizophrenia. An initial comparison with aged and sex matched normal controls showed an overall increase in slow wave activity in subjects with schizophrenia. The symptomatology of the subjects with schizophrenia was then factor analysed into three psychopathological syndromes that closely resembled Liddle's (1987b) original delineation. Correlations were undertaken between the three syndrome scores and qEEG. The "psychomotor poverty" factor was associated with increased beta activity most marked posteriorly and increased delta activity (accounted for by the effects of medication). The "disorganisation" factor was associated with widespread negative correlations in the alpha and beta bands and the "reality distortion" factor was associated positively with left anterior alpha activity. These distinct patterns of qEEG that clearly differentiate between the three syndromes, may contribute towards elucidating the underlying pathophysiological processes in schizophrenia. The results support the use of symptom based syndromes in reducing the diversity of findings in schizophrenia.

Adolescent↗

PubMed1996

[Long-term results of systematic treatment for nocturnal enuresis based on overnight simultaneous monitoring of electroencephalography and cystometry].

BACKGROUND: The long-term results of systematic treatment based on overnight simultaneous monitoring of electroencephalography (EEG) and cystometry in the patients with enuresis were evaluated. METHODS: From January to December a total of 213 patients were classified into 3 types. Enuresis Type I: such cases show a normal cystometrogram (CMG) with an awakening response on the EEG before enuresis, but they do not awake. Enuresis Type IIa; such cases show a normal CMG without an awakening response on the EEG. Enuresis Type IIb: such cases show an abnormal CMG with no awakening response on the EEG. When such cases enter the deep sleep stage, continuous uninhibited contractions of the bladder are observed on the CMG. 136 cases were of Type I, 20 cases of Type IIa, and 57 cases of Type IIb. RESULTS: Out of 213 patients who were followed up for 2 years, cured cases were 94 (44%), effective cases were 81 (38%) and unchanged cases were 38 (18%). In 136 patients with Type I, cured cases were 71 (52%), effective cases were 50 (37%) and unchanged cases were 15 (11%). In 20 patients with Type IIa, cured cases were 8 (40%), effective cases were 9 (45%) and unchanged cases were 3 (15%). In 57 patients with Type IIb, cured cases were 15 (26%), effective cases were 22 (39%) and unchanged cases were 20 (35%). The age of the effective group, which included cured cases and effective cases, was significantly higher than that of the unchanged group. In enuresis Type I, the percentage of the patients with incontinence in daytime were significantly in the unchanged group than in the effective group. No significant differences in the frequency of enuresis and the percentage of the patients who had awakened spontaneously by urinary sensation were found between the two groups. CONCLUSION: The therapeutic response was best in enuresis Type 1 and worst in enuresis Type IIb. The patients, in whom not only frequency of enuresis but also type of enuresis was unchanged by systematic treatment for two years, was approximately 10% across the types. Accordingly they were thought to be non-responders to this systematic treatment.

Child↗

PubMed1989

Overnight recordings of intracranial pressure and electroencephalography in neurosurgical patients. Part I: Intracranial pressure waves and their clinical correlations.

Simultaneous overnight recordings of intracranial pressure (ICP) and electroencephalography (EEG) were conducted on 85 neurosurgical patients with intracranial hypertension and/or ventriculomegaly. Intracranial pressure waves were classified into five types according to the pattern of appearance, and their correlation with sleep cycles and clinical conditions of patients were investigated. A-waves appeared exclusively in patients with long-standing intracranial hypertension, and episodic B-waves appeared in patients with chronic hydrocephalus or a postoperative tumor-free condition. When these episodic pressure waves appeared, the patients were conscious and sleep cycles including REM stage were observed. Persistent, high pressure B-waves were seen mostly in patients with an acute phase of intracranial hemorrhages. The consciousness of these patients ranged from drowsy to stupor. EEG showed alternate appearances of light sleep and waking rhythms in accordance with cyclic oscillations of B-waves which coincided with periodic, apneic respiratory rhythms. When markedly regular B-waves of moderately high pressure appeared continuously, the patients were severely impaired in consciousness and were mainly in a subacute phase of intracranial hemorrhages. EEG showed continuous slow activities and sleep stages were not scored in these patients. No characteristic clinical features were found in patients whose ICP remained within normal range without pressure waves throughout the recording.

Adolescent↗

PubMed1999

99mTc-HMPAO regional cerebral blood flow and quantitative electroencephalography in Alzheimer's disease: a correlative study.

UNLABELLED: In this study the neuropsychological status of patients with Alzheimer's disease (AD) was correlated with quantitative electroencephalography (qEEG) and regional cerebral blood flow (rCBF) both in the cortex and in deep gray matter structures. METHODS: Forty-three outpatients (mean age 72.4 +/- 7.5 y) with probable AD underwent 99mTc-hexamethyl propyleneamine oxime SPECT with a brain-dedicated gamma camera and qEEG (relative values) within 1 mo. Preliminary factorial analysis with promax rotation identified four qEEG bands (2-5.5, 6-7.5, 8-11.5 and 12-22.5 Hz, with no distinction as to topography) and six SPECT regions (the two thalami together, the two parietal cortices together, the right temporal cortex, the right hippocampus, the left hippocampus and the remaining cortical areas together) as the variables with highest statistical power. All these variables and the Mini-Mental Status Examination score (MMSE, a sensitive marker of neuropsychological deficit) were processed by a final factorial analysis and multivariate analysis of variance. RESULTS: Both the 2-5.5 Hz and the 8-11.5 Hz powers were correlated with the perfusion level in the parietal regions of interest (ROls) (P = 0.0009), whereas the 2-5.5 Hz power was correlated with the right hippocampal perfusion level (P = 0.007). The MMSE score was significantly correlated with the perfusion level, both in the right (P = 0.006) and in the left (P = 0.004) hippocampal ROls and in the parietal ROls (P = 0.01); moreover, it was correlated with both the 2-5.5 Hz (P = 0.0005) and the 8-11.5 Hz (P = 0.004) power. CONCLUSION: rCBF (bilateral parietal perfusion) and qEEG (especially the slowest frequencies, i.e., 2-5.5 Hz) are confirmed to be good descriptors of AD severity. It is especially noteworthy that bilateral hippocampal CBF was the perfusional index best correlated with the MMSE as well as being significantly correlated to qEEG. Hippocampal SPECT imaging appears to be a promising index to improve characterization of AD in respect to other forms of primary degenerative dementia and may be proposed as a marker for evaluating the effects of pharmacotherapy of AD at the neuronal level.

Aged↗

PubMed1999

Electroencephalography and magnetic resonance imaging after diving and decompression incidents: a controlled study.

Electroencephalography and magnetic resonance imaging after diving and decompression incidents: a controlled study. Undersea Hyper Med 1999.; 26(2):61-65.--Diving incidents with symptoms of decompression sickness (DCS) and/or arterial gas emboli (AGE) might increase the degree of pathologic change in the electroencephalogram (EEG) or magnetic resonance imaging (MRI) of the supraspinal central nervous system (CNS). Diving itself, even without known symptoms of DCS and/or AGE, has been proposed to increase the number of CNS lesions using either EEG or MRI. In the first part of a two-part study we examined the effects of recompression treatment on EEG in decompression incidents in a group of sport and professional divers compared with a control group of healthy naval divers. In the second part we recorded brain MRI from three groups of volunteers: 1) divers who were treated for DCS in pressure chamber, 2) divers who had never had symptoms of DCS (and/or AGE), and 3) healthy normal controls who were not divers. Our results indicate that DCS increases the incidence of pathologic EEG recordings, whereas recompression treatment decreases them. The results of MRI do not verify evidence of increased numbers of CNS lesions in normal divers as compared to non-diving, healthy control subjects, whereas some of the divers treated for DCS in a pressure chamber had hyperintense lesions in brain white matter. None of them had any abnormalities in EEG, neurologic performance, or psychologic behavior. Both EEG and MRI are sensitive and non-specific methods for judging suspected evidence of brain lesions from diving or diving accidents.

Adult↗

PubMedDate not supplied

Diagnostic validity of electroencephalography in equine intracranial disorders.

Electroencephalography (EEG) is a valuable diagnostic test to identify functional disturbances in brain activity. The purpose of this study was to assess the validity of EEG as a diagnostic indicator of intracranial diseases in horses. The validity of EEG was estimated by comparing clinical, clinicopathologic, and histopathologic findings to EEG findings in 20 horses examined for seizures. collapse, or abnormal behavior between 1984 and 1997. A bipolar left-to-right, back-to-front montage and a bipolar circular montage were recorded from sedated (4) and anesthetized (16) horses. Visual and semiquantitative masked analysis of EEG recording Ist was validated on 10 horses presented for problems other than intracranial diseases. EEG pattern was normal in 7 of the 20 clinically affected horses. Abnormal EEG patterns included high-voltage slow waves and discrete paroxysmal activity with or without generalized activity in 13 horses. Histopathologic diagnoses in 10 horses included meningoencephalitis, neuronal necrosis, congenital anomalies. cerebral edema. and abscess. All of these horses had abnormal EEG patterns (sensitivity, 100%) with a positive neuroanatomic correlation in 7 animals. Localization of histopathologic and EEG abnormalities did not correlate in 15% of the horses (3/20). The cause of neurologic signs could not be explained at postmortem examination in 10 animals and the EEG pattern was normal in 7 of these horses (specificity, 70%). In conclusion, equine EEG was a sensitive tool in the diagnosis of intracranial disorders.

Animals↗

PubMed1975

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↗

PubMed1975

[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↗

PubMedDate not supplied

Diagnostic investigations. Part 3. Electroencephalography.

Electroencephalography (EEG) is a non-invasive diagnostic procedure that involves the recording of electrical potential differences generated in the brain. The procedure is valuable in many aspects of neurology, particularly in the diagnosis of epilepsy. This article explains the procedure, what the results can indicate and the nursing care involved.

Brain Neoplasms↗

PubMed2002

[A case of acute measles encephalitis with periodic synchronous discharge on electroencephalography].

A 18-year-old man was diagnosed as having measles on the basis of cutaneous and mucosal eruption and high grade fever on May 10, 2001. Six days after the skin eruption, the patient developed general convulsion (day1). He was admitted to our hospital because of status epilepticus. We made a diagnosis of acute measles encephalitis, based on the clinical features and pleocytosis with an increase in protein in the cerebrospinal fluid. Under artificial ventilation and sedation, he received intravenous immunoglobulin and dexamethasone. Electroencephalography (EEG) on day 4 revealed periodic synchronous discharge (PSD). Significant elevation of antibody titer for measles virus was found in the serum, but not in the cerebrospinal fluid. Polymerase chain reaction method did not show viral genes of measles virus, herpes simplex virus and herpes zoster virus. Serial EEG studies demonstrated a decrease in PSD, followed by irregular spike-wave complexes within 20 days. He recovered completely one month after the onset. It should be kept in mind that PSD can emerge on EEG in the early stage of acute measles encephalitis.

Acute Disease↗

PubMed2003

Effect of Ginkgo biloba leaf extract on electroencephalography of rat with cerebral ischemia and reperfusion.

AIM: To test the effect of Ginkgo biloba leaf extract on electroencephalography (EEG) during cerebral ischemia and reperfusion. METHODS: Based on the quantitative analysis of EEG using the fast Fourier transform (FFT), the effect of Ginkgo biloba extract (GbE) on rat EEG was surveyed in the model of middle cerebral artery (MCA) occlusion and global cerebral ischemia. RESULTS: In the global cerebral ischemia, GbE 8 and 16 mg/kg could accelerate the recovery of EEG after reperfusion, and GbE 4 mg/kg had the same effect but much weaker. In the MCA occlusion model, GbE 16 and 32 mg/kg greatly suppressed the drop of power spectrum of EEG. CONCLUSION: GbE could mitigate the cerebral damage caused by ischemia.

Animals↗