Amplitude-integrated electroencephalography in newborns with inborn errors of metabolism

Background: The utility of amplitude-integrated electroencephalography (aEEG) monitoring has been established for patients with neonatal hypoxic-ischemic encephalopathy. Objective: To evaluate the role of aEEG in the diagnostic process and treatment of patients with encephalopathy due to inborn errors of metabolism. Methods: Cases collected through an international registry were divided into 5 groups of metabolic disorders. Common aEEG features were sought for each group. Results: In total, 21/30 (70%) cases had abnormal aEEG background patterns, 18/30 (60%) showed seizure activity. Patients with disorders of energy metabolism, hyperammonemia, and organic/amino acidopathies often showed marked aEEG depression with seizure activity. In contrast, aEEGs of patients with peroxisomal disorders did not show major background abnormalities but seizures were present in 5/6 subjects. We report two features of interest: firstly, two tracings displayed an unusual upward shift of the lower aEEG amplitude margin. Secondly, aEEGs of infants with non-ketotic hyperglycinemia showed a pattern we refer to as 'high-frequency burst-suppression pattern'. Conclusions: aEEG in patients with inborn errors of metabolism frequently reveals abnormalities and assists clinicians in the clinical assessment, management and monitoring of these patients.     

Utility of prolonged bedside amplitude-integrated encephalogram in encephalopathic infants

We hypothesized that prolonged bedside limited-channel amplitude-integrated electroencephalogram (aEEG) monitoring following a standard 1-hour conventional electroencephalogram (cEEG) would increase the detection of subclinical seizures and allow continuous evaluation of the background EEG in neonatal encephalopathy. This may identify complementary roles for these EEG technologies in neonatal units where continuous cEEG monitoring may not be readily available. We prospectively recruited 25 term neonates with a diagnosis of neonatal seizures or encephalopathy. All infants underwent a standard 1-hour cEEG followed by 12 to 24 hours of aEEG monitoring. Data from the aEEG (plus the raw signal) were analyzed by an epileptologist and compared with information obtained from the clinical report of the cEEG. aEEG and cEEG data were available for 24 infants. Results from magnetic resonance imaging (MRI) performed at 7 to 10 days of life were available in 23/24 infants. Background classification on cEEG and aEEG was similar in 83% of patients. Five of 24 infants had normal background on cEEG. Prolonged aEEG detected evolution of background from initially normal to moderately abnormal in an additional four infants. It also detected more subclinical seizures than the 1-hour cEEG in 8/14 infants. Normal background on aEEG and cEEG was associated with normal MRI results, and severe background abnormality (5/24) on both aEEG and cEEG was associated with abnormal MRI results. Data obtained from prolonged aEEG (plus raw EEG) provide similar background activity, enhance seizure detection, and complement standard cEEG in predicting short-term outcomes, based on MRI, in term neonates with seizures or encephalopathy. Limited-channel aEEG technology may provide a pragmatic alternative for longitudinal monitoring of newborn infants with encephalopathy in neonatal units where prolonged video EEG monitoring is not feasible.     

Amplitude-integrated EEG in preterm infants: maturation of background pattern and amplitude voltage with postmenstrual age and gestational age.

OBJECTIVE: Amplitude-integrated electroencephalogram (aEEG) is a single channel EEG recorded from two parietal electrodes. The objective of this study was to test the hypothesis that aEEG maturation follows postmenstrual age (PMA) irrespective of gestational age (GA). METHODS: We recruited inborn infants with a GA <33 weeks and without evidence of neurologic anomaly. Serial aEEG recordings were assessed for: presence of continuous activity and mature sleep-wake cycling (SWC); low base voltage (V), that is, the lowest amplitude margin; high base V, that is, the most common amplitude margin; upper high V, that is, upper margin during highest activity; and span, that is, the difference between upper high and simultaneous high base V. Statistical analysis included logistic regression and repeated measures analysis of variance. RESULTS: We obtained 119 aEEG recordings in 31 preterm infants (GA 25 to 32 weeks; birth weight 600 to 1704 g, PMA 25 to 35 weeks). The frequency of mature SWC increased with PMA independent of GA, while the frequency of continuity increased with PMA and was higher in extremely preterm infants after correcting for PMA. Low base and high base V increased with PMA, while span and upper high V significantly decreased with PMA. In addition, high base V was higher in extremely preterm infants after correcting for PMA. CONCLUSIONS: In preterm infants aEEG matures predominantly with PMA. Our data suggest that some aspects of aEEG maturation are enhanced, rather than inhibited by extremely preterm birth. These data suggest that aEEG in preterm infants may need to be analyzed by comparing results with standards of similar PMA and GA.     

振幅整合脑电图预测足月儿缺氧缺血性脑病预后的meta分析

目的 评价振幅整合脑电图(amplitude-integrated EEG,aEEG)判断足月儿缺氧缺血性脑病(hypoxic-ischemic encephalopathy,HIE)预后的价值. 方法 计算机检索EMBASE、Ovid、PubMed、Cochrane图书馆、Springer数据库、中国生物医学文献数据库、中国期刊全文数据库和万方数据库等数据库,检索时间为各数据库建库时间至2010年6月30日.全面检索aEEG判断新生儿HIE预后的文献,提取纳入文献的特征信息,评价纳入文献质量.采用Meta-Disc1.4软件进行meta 分析,对纳入文献予以加权定量合并,计算汇总敏感度、特异度、阳性似然比、阴性似然比及其95％CI. 结果 共有11篇文献符合既定标准纳入分析,共纳入病例717例.aEEG预测足月新生儿HIE神经发育不良的汇总敏感性为86％(95％ CI:81％～89％)、汇总特异性为90％(95％ CI:86％～93％)、汇总阳性似然比为7.70(95％ CI:5.69～10.43)、汇总阴性似然比0.17(95％ CI:0.13～0.22),汇总受试者工作特性曲线的曲线下面积为0.95. 结论 aEEG是有价值的预测足月儿HIE预后的床旁监测工具.     

Training neonatal staff in recording and reporting continuous electroencephalography

Continuous electroencephalography can contribute useful information to clinical decision-making in neonatal care. Equipment is now reliable and user-friendly enough that its use can be taught to medical and nursing staff so that a 24-hour capability is achieved. It is possible to teach neonatologists, in a 1-day course, background knowledge on EEG and amplitude-integrated EEG (aEEG), recognition of aEEG patterns that have clinical significance, recognition of seizures using aEEG and "raw" EEG, the essentials of electrode placement for aEEG, and interpretation of findings in the clinical context. This must be followed up by background reading, frequent peer-review sessions on EEG recordings, and a reliable system for storing and access, as well as willingness to consult experienced operators elsewhere.     

Continuous electroencephalography monitoring of the preterm infant

Continuous electroencephalography (EEG) monitoring provides clinically relevant information in preterm infants. Acute changes during development of intraventricular hemorrhage and white matter injury are associated with EEG and amplitude-integrated EEG (aEEG) deterioration. The early EEG background is also correlated with outcome in preterm infants, although other problems associated with prematurity may influence the long-term prognosis. The limitations of EEG monitoring should be well-understood by users and the continuous EEG monitor should be used as a complement to the standard EEG.     

Effect of caffeine on preterm infants’ cerebral cortical activity: an observational study

Objective: Our first aim was to investigate the effects of caffeine on preterm infants' respiratory functions and brain cortical activity (conventional and amplitude-integrated electroencephalography (cEEG and aEEG)). Secondary aim was to study its long-term effects on respiratory system and electroencephalographic maturation by 36 weeks post-menstrual age.

Methods: Prospective observational study on 33 consecutively admitted preterm infants less than 34-weeks-gestation. cEEG and aEEG, cardiopulmonary and sleep state were recorded in 20 preterm infants, before, during and 2-hours after intravenous (IV) caffeine (caffeine Group), and for 13 preterms (control group). Both groups were subjected to assessment of cerebral cortical maturation by cEEG and aEEG at 36-weeks post-menstrual age as an outcome measure.

Results: IV caffeine administration significantly increased heart rate (p?=?0.000), mean arterial blood pressure (p?=?0.000), capillary oxygen saturation (p?=?0.003), arousability (p?=?0.000) and aEEG continuity (p?=?0.002) after half an hour. No clinical seizures were recorded and non-significant difference was found in electrographic seizures activity in cEEG. At 36-weeks post-conceptional age, NICU stay was significantly longer in controls (p?=?0.022). aEEG score was significantly higher in caffeine group than the control group, (p?=?0.000).

Conclusions: Caffeine increases preterm infants’ cerebral cortical activity during infusion and results in cerebral cortical maturation at 36weeks, without increase in seizure activity.     

REVIEW: New Electroencephalogram (EEG) Neuroimaging Methods of Analyzing Brain Activity Applicable to the Study of Human Sexual Response

IntroductionElectroencephalogram (EEG) combined with brain source localization algorithms is becoming a powerful tool in the neuroimaging study of human cerebral functions.AimThe present article provides a tutorial on the various EEG methods currently used to study the human brain activity, notably during sexual response.Main Outcome MeasuresReview of published literature on standard EEG waveform analyses and most recent electrical neuroimaging techniques (microstate approach and two methods of brain source localization).MethodsRetrospective overview of pertinent literature.ResultsAlthough the standard EEG waveform analyses enable millisecond time-resolution information about the human sexual responses in the brain, less is clear about their related spatial information. Nowadays, the improvement of EEG techniques and statistical approaches allows the visualization of the dynamics of the human sexual response with a higher spatiotemporal resolution. Here, we describe these enhanced techniques and summarize along with an overview of what we have learned from them in terms of chronoarchitecture of sexual response in the human brain. Finally, the speculation on how we may be able to use other enhanced approaches, such as independent component analysis, are also presented.ConclusionsEEG neuroimaging has already been proven as a strong worthwhile research tool. Combining this approach with standard EEG waveform analyses in sexual medicine may provide a better understanding of the neural activity underlying the human sexual response in both healthy and clinical populations. Ortigue S, Patel N, and Bianchi-Demicheli F. New EEG neuroimaging methods of analyzing brain activity applicable to the study of human sexual response. J Sex Med 2009;6:1830–1845.     

What does cyclicity on amplitude-integrated EEG mean?

In the context of amplitude-integrated electroencephalography (aEEG), the term 'sleep-wake cycling' (SWC), which is frequently used by clinicians and researchers, should be changed to 'cyclicity'. SWC is a technical term that refers to the biological pattern of alternating sleeping and waking states, which is difficult to define with only aEEG and no physical parameters. Additionally, the absence of cyclicity on aEEG is a more robust reflection of the sequence of the suppressed background patterns of an aEEG following cerebral injury or dysfunction than are sleep/wake states.     

Computer Processed Electroencephalogram Signals Compared to Conventional EEG Signals in Preeclamptics

Monitors that use computer processed EEG signals have been developed to simplify recognition and interpretation of EEG changes. The information from one of these monitors was compared with signals obtained by simultaneous conventional EEG recordings in eight awake preeclamptics. All eight of the processed tracings were read as abnormal, while only one of the 16 channel conventional EEG recordings was abnormal. We conclude that this particular monitor will not be beneficial for assessing continuous brainwave activity in awake/drowsy preeclamptic women.     

Effect of essential oil and supercritical carbon dioxide extract from the root of Angelica gigas on human EEG activity

ObjectivesThe present study aimed to investigate the effect of inhalation of essential oil (EO) and supercritical carbon dioxide extract (SC-CO₂) from the root of A. gigas on human electroencephalographic (EEG) activity.Materials and methodsFor this purpose, the EO was obtained from the root of A. gigas by steam distillation and SC-CO₂ was obtained at 50 °C and 400 bar for 1 h. The EEG readings were recorded using the QEEG-8 system from 8 electrode sites according to the International 10-20 system.ResultsIn the EEG study, the absolute low beta (left temporal and left parietal) activity significantly increased during the inhalation of EO. In the case of SC-CO₂ inhalation, there was no significant change in absolute waves.ConclusionThe results revealed that the EO of A. gigas root produced significant changes in the absolute low beta activity and these changes may enhance the language learning abilities of human brain.     

儿童颅脑外伤后癫疒间发作的脑电图及其随访

目的探讨儿童被家长击打头部后癫疒间发作的脑电图及随访脑电图的变化。 方法商丘市第二人民医院于1990-1999年，对36例头部被家长击打后癫疒间发作患儿行脑电图检查并进行3~8年的随访。 结果36例中脑电图异常32例(889%)，其中有疒间样放电者28例(875%,28/32)；随访脑电图异常消失22例(687%,22/32)，疒间样放电消失18例(643%，18/28)。常规记录即有疒间样放电、背景节律以慢波为主、临床发作较晚(>1周)者疒间样放电较难消失(均P<005)。首次脑电图有疒间样放电者临床发作较难控制(P<005)，随访脑电图疒间样放电不消失者临床发作更难控制(P<001)。 结论儿童头部被家长击打后癫疒间发作的脑电图异常率高，疒间样放电消失与否与疒间样放电的特点及临床发作早晚有一定关系，且对临床预后产生较大影响，应引起重视。     

A novel EEG for alpha brain state training,neurobiofeedback and behavior change

Mindfulness meditation, with the resulting alpha brain state, is gaining a strong following as an adjunct to health, so too is applying self-affirmation to stimulate behavior change through subconscious re-programming. Until recently the EEG technology needed to demonstrate this has been cumbersome and required specialist training. This paper reports a pilot study using a remote EEG headband, which through a sophisticated algorithm, provides a real-time EEG readout unencumbered by conventional artifacts. In a convenience sample of 13, the difference in brain waves was examined while the subjects were occupied in an ‘attention’ and an ‘alpha mind state’ exercise. There was a significant difference in the mean scores for theta, delta, beta and gamma brain waves. Alpha brain waves remained static suggesting an ability of the headset to discriminate a mindful state and to provide real-time, easy to interpret feedback for the facilitator and subject. The findings provide encouragement for research applications in health care activities providing neurobiofeedback to subjects involved in mindfulness behavior change activities.     

BRCA1 and BRCA2 gene mutations: decision-making dilemmas concerning testing and management

The identification of the BRCA genes, and their possible etiologic relationship with various forms of inherited cancer, has been recognized universally as a cornerstone in the search of cancer's genetic susceptibility. Female BRCA gene mutation carriers are found to carry an increased risk of developing breast or ovarian cancer and to a lesser degree, colon cancer, and male BRCA mutation carriers are also related to an increased risk of breast, colon, or prostate cancer. Although genetic testing promises a possible future presymptomatic determination and treatment of women who are genetically susceptible to cancer, current data reveal certain dilemmas and uncertainties regarding our ability to interpret the results from testing and offer effective management options. In addition, several complex ethical, legal, and social issues have been revealed with the advent of this new information, which also confirm the need for additional research regarding the most effective use of this genetic information and for the establishment of appropriate clinical management strategies.     

Comparison of cerebral magnetic resonance and electroencephalogram findings in pre-eclamptic and eclamptic women

OBJECTIVE: To compare the cerebral magnetic resonance (MR) and electroencephalogram (EEG) findings in pre-eclamptic and eclamptic pregnant women. METHODS: A total of 38 pregnant women with mild pre-eclampsia (n = 15), severe pre-eclampsia (n = 11) and eclampsia (n = 12) were included in this study. Cranial MR without contrast and EEG were performed in these women on admission or within 3 days of onset. Follow-up control MR or EEG evaluations were performed 4-6 weeks postpartum in women with MR or EEG abnormalities in the initial examination. To compare differences, X(2) test, Fisher exact or Mann-Whitney U-tests were used. RESULTS: Abnormal cranial MR findings were found in one (6%) pre-eclamptic woman, in four (36%) severe pre-eclamptic women, and in 11 (92%) eclamptic women. Cranial MR findings were consistent with ischaemia in 15 (39%) patients and haemorrhage in one (3%) case. Two (5%) severe pre-eclamptic women showed cerebral infarction during the follow-up period. MR and EEG abnormalities were totally resolved in 88% of cases. The MR findings of 12 (71%) patients were located in the occipital lobes followed by the parietal lobes in six (40%) cases. Three (20%) mild pre-eclamptic women, four (36%) severe pre-eclamptic women and 10 (83%) eclamptic women had abnormal EEGs. The EEG changes were totally resolved in 13 of 14 (93%) patients after the first month. In one patient with cerebral haemorrhage, the EEG changes lasted for a duration of 6 months. CONCLUSIONS: A correlation between EEG abnormalities and MR findings was found in this study. The combined use of MR and EEG may help to determine the prognosis for these patients, but the interictal EEG findings recorded in eclampsia were non-specific.     

The effect of elevated blood glucose on the electroencephalogram and cerebral metabolism during short-term brain ischemia in fetal sheep

The effect of cerebral ischemia on cerebral metabolism and the electroencephalogram was studied with and without prior glucose infusion in near-term normoxic fetal sheep. At normal blood glucose levels, the electroencephalogram decreased in amplitude during ischemia. At elevated blood glucose levels the electroencephalographic amplitude was much less attenuated by ischemia although Fast Fourier Transforms revealed a shift toward slower frequencies. Under either normal or elevated blood glucose conditions, ischemia caused cerebral oxygen consumption to decrease, glucose uptake to increase, and a net efflux of lactate to occur. Elevated blood glucose appears to help maintain electroencephalographic activity during ischemia, perhaps by fueling additional anaerobic energy production. The relationship between the electroencephalogram, brain metabolism, and brain damage remains to be defined.     

Prefrontal EEG Correlation During Tower of Hanoi and WCST Performance: Effect of Emotional Visual Stimuli

IntroductionEmotional stimuli elicit changes in the electroencephalographic (EEG) activity of several brain structures. Prefrontal cortex is involved in the processing of emotional stimuli and executive functions. The correlation analysis of EEG provides information about the functional coupling between areas. It is reasonable to expect that emotional activation will modify prefrontal coupling during the performance of executive tasks such as Tower of Hanoi or Wisconsin Card Sorting Test (WCST).AimDetermine whether the prefrontal EEG correlation during the performance of the Tower of Hanoi and WCST is affected by previous exposure to videos with sexual or aggressive content.Main Outcome MeasuresPrefrontal EEG coupling was determined by the Pearson correlation. Valence and general arousal were evaluated by the Self‐Assessment Manikin Scale and sexual arousal with a Sexual Arousal Scale. Computerized versions of the Towers of Hanoi and WCST provided data on prefrontal executive functions.MethodsEEG from the left and right prefrontal zones was recorded during the performance of the Tower of Hanoi and WCST immediately after the subjects were exposed to one of the videos (neutral, aggressive, and erotic).ResultsThere was no difference between videos in the task performance parameters. Only the erotic video produced an increased prefrontal coupling in the slow bands (delta and theta) during the performance of the Tower of Hanoi, whereas a decreased coupling in the delta, theta, and alpha bands was observed during the WCST.ConclusionsPrefrontal coupling was changed after exposure to the erotic video, and it is likely that enhanced sexual arousal was the main cause of this change. The correlation patterns obtained could be associated with particular cognitive strategies or to functional adaptations while being sexually aroused. The results of this study may contribute to an understanding of the central nervous mechanisms underlying the cognitive effects of sexual arousal. Ruiz‐Díaz M, Hernández‐González M, Guevara MA, Amezcua C, and Ågmo A. Prefrontal EEG correlation during Tower of Hanoi and WCST performance: Effect of emotional visual stimuli. J Sex Med **;**:**–**.     

表现为过度运动发作的儿童部分性癫痫7 例临床分析

摘要：目的　探讨表现为过度运动发作（HMS）的儿童部分性癫痫的临床特征。方法　对2003年6月至2009年1月首都儿科研究所神经科门诊或病房符合诊断标准的7例患儿进行发作期及发作间期视频脑电图监测,观察临床发作症状及发作期、发作间期脑电图表现,并追踪抗癫痫药物疗效。结果　7例患儿视频脑电图共记录到29次发作,持续时间10～84 s,22次发生于睡眠,7次发生于清醒。发作时均有程度不同的躁动不安,过度运动行为表现多样,包括拍手、挥舞、挥拳、拍打、抓物、蹬踏、蹦跳等上、下肢动作,髋部水平移动,由平卧欲坐起动作,过度运动以外动作包括眼、头颈、躯干向一侧扭转、姿势性强直、表情恐惧或愤怒、面部涨红等。发作间期脑电图,除1例未见异常波形外,余6例均可见异常波形,表现为双侧或一侧额、额极导联棘波、尖波;7例发作期脑电图均为单或双侧额极、额起源的低幅快波节律,继而被大量动作伪迹掩盖,发作后渐恢复原背景。结论　HMS是部分性癫痫的一种发作形式,发作时以明显躁动的过度运动为特征,可伴有不对称强直姿势及表情变化,发作期脑电图均表现为单或双侧额极、额导联起源的低幅快波节律,卡马西平或奥卡西平有效,多数患儿可达到满意效果。     

EEG during different emotions in 10-month-old infants of depressed mothers

EEG activity of 10-month-old infants of depressed and non-depressed mothers was compared during stimuli designed to produce happy and sad responses. During a baseline recording and during their happy facial expressions, infants of depressed mothers showed greater relative right frontal EEG asymmetry compared to infants of non-depressed mothers. The greater relative right frontal EEG asymmetry was also noted during a play interaction with their mothers. Infants of depressed mothers also showed more negative and less positive expressions. These findings are discussed in relation to the theory that frontal EEG activity may be a biological marker for symptoms associated with depression.