Early serial EEG in hypoxic ischaemic encephalopathy.

OBJECTIVES: To perform early serial EEGs in infants with hypoxic ischaemic encephalopathy (HIE) and compare the findings with neurodevelopmental outcome. METHODS: Nine full-term neonates with HIE had simultaneous video-EEG polygraphic studies within 8 h of birth. The EEG was repeated at 12-24 h intervals. All surviving infants had a neurodevelopmental assessment at 1 year. RESULTS: Two infants had a normal or mildly abnormal EEG within 8 h of birth and neurodevelopmental outcome was normal. Seven infants had severely depressed background activity in the first 8 h of life. In 3 infants the EEG activity recovered within 12-24 h showing continuous activity with no or only minor abnormalities. All these infants had a normal outcome. The remaining 4 infants, who also had an initially inactive recording, subsequently developed severe background abnormalities. At follow-up, two infants had died and the remainder developed major neurological sequelae. CONCLUSIONS: Early EEG is an excellent prognostic indicator for a favourable outcome if normal within the first 8 h of life and for a poor outcome if the background activity continues to be inactive or grossly abnormal beyond 8-12 h of life. However, an inactive or very depressed EEG within the first 8 h of life can be associated with good outcome if the EEG activity recovers within 12 h.     

Burst suppression electroencephalogram pattern in the newborn: predicting the outcome

A neonatal burst suppression electroencephalogram (EEG) is usually associated with an ominous prognosis. It is controversial whether a reactive burst suppression pattern (ie, a burst suppression pattern that can be interrupted by stimulation) is predictive of a better outcome. We retrospectively studied 22 full-term newborns with burst suppression EEGs to examine their functional outcome. Follow-up (3 to 9 years) was by record review and telephone interview. On the basis of initial EEG pattern and prognosis, three groups were identified post hoc: group 1 (n = 16) had initially nonreactive burst suppression EEGs that remained abnormal; 11 patients died, 4 remained profoundly impaired (nonambulatory, nonverbal), and 1 was moderately impaired (unassisted ambulation, limited speech). Group 2 (n = 3) had initially nonreactive burst suppression EEGs that later improved substantially (within a mean of 7 weeks). At follow-up (3 to 8 1/2 years), each child was waLking (one with braces), talking, and enrolled in special education. Group 3 (n = 3) had reactive burst suppression EEGs initially. At follow-up (ages 3 1/2 to 9 years), each child was walking unassisted and speaking in sentences. Two children in group 3 were of preschool age, and the third was in a special needs program. Although most newborns with nonreactive burst suppression EEGs have a dire neurologic outcome, of those in whom the EEG improves early, the prognosis may be slightly more favorable. Infants with reactive burst suppression EEGs during the acute phase of illness appear to have the best prognosis.     

Neurological and perceptual-motor outcome at 5 - 6 years of age in children with neonatal encephalopathy: relationship with neonatal brain MRI

OBJECTIVE: The aims of this study were 1) to determine the incidence of minor neurological dysfunction and perceptual-motor difficulties in children aged 5-1/2 -- 6-1/2, who had been born full-term but presented with neonatal encephalopathy (NE) and low Apgar scores and 2) to examine the relationships between the presence/absence of these difficulties with neonatal brain MRI. PARTICIPANTS AND METHODS. Sixty-eight full-term infants with one minute Apgar scores less than or equal to 5 and neurological abnormalities during the first 48 hours after birth were included in the study. All children had a neonatal MRI brain scan. Surviving infants were assessed between the age of 5 and 6 years using the Touwen Examination, the Movement ABC and the WPPSI-R. RESULTS: Fifteen of the 68 infants (22 %) died in the neonatal period. Of the 53 surviving infants, 19 (36 %) had cerebral palsy. The remaining 34 were considered normal at 2 years of age but, when assessed at school age, 8 (15 %) had minor neurological dysfunction and/or perceptual-motor difficulties, 1 (2 %) had only cognitive impairment and 25 (47 %) were normal. The outcome largely reflected the pattern of lesions on brain imaging. While 83 % of those with a normal outcome had normal scans or minimal white matter lesions, 80 % of those with minor neurological dysfunction and/or perceptual-motor difficulties had mild or moderate basal ganglia or more marked white matter lesions. CONCLUSION. Continued surveillance is recommended for children with apparently normal outcome at two years of age after NE, particularly when abnormalities are detected on brain MRI.     

Evaluation of serial EEG recordings and auditory brainstem responses in the early preterm infants]

EEGs were recorded serially throughout the neonatal period and auditory brainstem responses (ABRs) in the late neonatal period in 105 preterm infants with the gestational age of less than 33 weeks and birth weights of less than 1,750g in order to study the relation between abnormal findings and neurological outcome. A study of serial EEG recordings revealed that a disorganized pattern following severe depression of background EEG activities was closely associated with deep white matter injuries detected by ultrasonography and that infants showing such features are likely to suffer from cerebral palsy. On the other hand, a dysmature pattern was often observed following prolonged mild depression, although no abnormalities were apparent on ultrasonography. This EEG pattern was more often associated with mental impairment. Any findings of ABRs were not associated with adverse outcome. We conclude that serial EEG recordings during the neonatal period in preterm infants are useful in clarifying the extent and nature of brain injury as well as future developmental problems.     

Prognostic value of non-reactive burst suppression EEG pattern associated to early neonatal seizures

Seizures are the most frequent neurological event in newborns and clinical data suggest that etiology is the dominant factor in long term outcome. However, there are consistent background EEG abnormalities associated to neonatal seizures that are usually related to unfavorable outcome as the burst-suppression pattern. OBJECTIVE: The objective of this study was to correlate clinical and EEG features associated to long-term outcome of newborns with non-reactive burst-suppression (BS) EEG. METHOD: Newborns included in the study were selected from our database and had conceptional age (at the time of first EEG) >37 weeks, EEG recordings with non-reactive BS available for review and clinical follow up. RESULTS: 12 newborns met inclusion criteria, 50% had seizures in the first day of life. Seizures became refractory to treatment in all of them. In 50% the etiology of seizures was considered cryptogenic, 33% had inborn errors of metabolism and 17% had clinical history and neuroimage suggestive of hypoxic-ischemic encephalopathy. The follow-up showed that 7/12 infants deceased, 3 during the first year of life, and one in the neonatal period. All the survivors had severe developmental delay and multifocal neurological impairment. 92% developed refractory epilepsy, 58% were latter diagnosed with West syndrome. CONCLUSION: The non-reactive BS pattern may appear related to many neonatal neurological disorders and is associated with early and refractory neonatal seizures. It is clearly associated with elevated morbidity and mortality and to the development of post-neonatal epilepsy.     

Motor outcome at the age of one after perinatal hypoxic-ischemic encephalopathy

OBJECTIVE: The aim of this report is to describe the motor outcome in one year-old children who were born at full-term with perinatal hypoxic-ischemic encephalopathy (HIE). Relationships between motor ability tests and neurological examination at one year, and between these tests and neonatal brain magnetic resonance imaging (MRI) were investigated. PARTICIPANTS AND METHODS: 32 surviving children, born full-term with perinatal HIE, are included in this report. All children had a neonatal MRI. At one year, motor ability was assessed with the Alberta Infant Motor Scale and the Bayley Scales of Infant Development (2nd version). Neurological examinations included the neurological optimality score (NOS). RESULTS: At one year, 14 children (44%) had normal motor ability, nine (28%) had mildly delayed, and nine had significantly delayed motor ability. The NOS ranged from 14.6-27 points. All children with normal motor ability had (near) optimal NOS, however, not all children with high NOS had normal motor ability. Eleven children (34%) had normal neonatal MRI; at one year, six of them had normal, and five had mildly delayed motor ability. Eight children with normal motor ability showed abnormalities on neonatal MRI. CONCLUSION: Neonatal brain MRI does not predict motor outcome at one year. Motor ability tests and neurological examinations should be used in a complementary manner to describe outcome after HIE.     

Neonatal neurological examination in infants with hypoxic ischaemic encephalopathy: correlation with MRI findings.

Neurological examination and magnetic resonance imaging were performed in the neonatal period in 58 full-term infants who presented with hypoxic-ischaemic encephalopathy. The aim of this study was to evaluate the patterns of neurological abnormalities and their correlation to brain lesions on MRI. The prognostic value of the neurological examination performed at different times in the neonatal period was also evaluated. Our results showed that specific clinical patterns can be observed in infants with HIE and these can be related to the pattern of lesion on brain MRI. In particular, while infants with normal MRI or minimal changes tend to show only minor tone abnormalities after the first week of life, infants with more severe lesions such as basal ganglia lesions show persistent and diffuse neurological abnormalities. Infants with white matter changes but intact basal ganglia show a different clinical pattern with improved sucking reflex and behaviour and less severe tone abnormalities. Our results also suggested that the neurological examination performed after the second week of life is a reliable indicator of outcome in these infants.     

Amplitude-integrated EEG is useful in predicting neurodevelopmental outcome in full-term infants with hypoxic-ischemic encephalopathy: a meta-analysis

Hypoxic ischemic encephalopathy is a common cause of neurological complications resulting in chronic handicapping conditions, such as cerebral palsy. Amplitude-integrated electroencephalography (EEG) has been used in many European countries for more than a decade in the evaluation of infants with hypoxic ischemic encephalopathy but has not been widely used in the United States. The objective of this study was to evaluate the evidence supporting use of amplitude-integrated EEG as a quantitative predictor of neurodevelopmental outcome in full-term infants with hypoxic ischemic encephalopathy. To assess efficacy, the authors performed a meta-analysis of the literature evaluating the use of the amplitude-integrated EEG or cerebral function monitor in full-term infants with hypoxic ischemic encephalopathy and their neurodevelopmental outcome. A total of 8 studies were eligible for the primary meta-analysis. There was an overall sensitivity of 91% (95% CI 87-95) and a negative likelihood ratio of 0.09 (95% CI .06-.15) for amplitude-integrated EEG tracings to accurately predict poor outcome. Amplitude-integrated EEG is a valuable bedside tool for predicting long-term neurodevelopmental outcome in term infants with hypoxic ischemic encephalopathy. This information is useful in structuring communication and care plans for physicians and parents. Early assessment techniques such as amplitude-integrated EEG provide objective means for determining inclusion in clinical studies evaluating therapies for hypoxic ischemic encephalopathy and for predicting which patients are most likely to respond to treatment.     

Video/EEG aspects of early-infantile epileptic encephalopathy with suppression-bursts (Ohtahara syndrome).

Early-infantile epileptic encephalopathy (EIEE) with suppression-bursts is a severe neonatal epileptic encephalopathy. The etiology is multiple, with cerebral malformations as the more frequent. We review the clinical and video/EEG aspects of eight infants with EIEE. These infants, aged between 4 and 70 days at the time of video/EEG recordings, were studied in relation to their clinical and video/EEG characteristics, evolution, persistence of suppression-burst pattern and etiology. Seven of the eight infants showed an ictal clinical sign correlated to the burst of the suppression-burst pattern, four of whom died within 11 months of age. The other three are alive. One, now aged 4 years, underwent surgery for hemimegalencephaly and is seizure-free, with good neurological outcome. One, now aged 9 months, was pyridoxine-dependent and she is seizure-free, and with normal neurological evolution under pyridoxine therapy. One, now aged 3 years and 9 months, is seizure-free, but with severe neurological and cognitive impairment. The only child who did not show a clinical ictal correlation of burst is also alive, now aged 3 years and 9 months, with drug-resistant epilepsy, and severe neurological and cognitive deficits. With regard to the etiology, three showed structural abnormalities, two more showed some signs of prenatal origin of neurological disease, and three had metabolic etiology. Our study confirms that EIEE is a severe age-dependent early epileptic encephalopathy. The etiology is mostly malformative. The prognosis is poor regarding motor and cognitive development, seizures, as well as life expectancies. The presence of an ictal burst of the suppression-burst pattern usually correlates with a negative outcome.     

Normally developed infant with a suppression burst pattern on electroencephalography in the neonatal period

The background activity on neonatal electroencephalography (EEG) is a good prognostic indicator. An EEG suppression burst pattern usually indicates severe brain dysfunction and has been considered to be associated with a serious neurodevelopmental outcome. We report here a 2-year-old girl who developed generalized convulsions without any perinatal brain insult at 3 days of age. At that time, her EEG constantly showed a suppression burst pattern, and her prognosis was considered to be poor. However, her seizures were well controlled with the oral administration of carbamazepine, and the suppression burst pattern on EEG disappeared at 27 days of age. Unexpectedly, she developed normally for the following 2 years. Although children with normal development, despite the appearance of suppression burst, are extremely rare, and the reason why this patient showed a favorable outcome remains unknown, the clinical course of this patient proved that an EEG suppression burst pattern is not always associated with a poor prognosis.     

Quantitative approach to early neonatal EEG visual analysis in hypoxic-ischemic encephalopathy severity: Bridging the gap between eyes and machine

ObjectivesTo identify relevant quantitative parameters for early classification of neonatal hypoxic-ischemic encephalopathy (HIE) severity from conventional EEGs.MethodsNinety EEGs, recorded in full-term infants within 6 h of life after perinatal hypoxia, were visually classified according to the French EEG classification into three groups of increasing HIE severity.Physiologically significant EEG features (signal amplitude, continuity and frequency content) were automatically quantified using different parameters. The EEG parameters selection was based on their ability to reproduce the visual EEG classification. Post hoc analysis based on clinical outcome was performed.ResultsSix EEG parameters were selected, with overall EEG classification performances between 61% and 70%. All parameters differed significantly between group 3 (severe) and groups 1 (normal-mildly abnormal) and 2 (moderate) EEGs (p < 0.001). Amplitude and discontinuity parameters were different between the 3 groups (p < 0.01) and were also the best predictors of clinical outcome. Conversely, pH and lactate did not differ between groups.DiscussionThis study provides quantitative EEG parameters that are complementary to visual analysis as early markers of neonatal HIE severity. These parameters could be combined in a multiparametric algorithm to improve their classification performance. The absence of relationship between pH lactate and HIE severity reinforces the central role of early neonatal EEG.     

Prognostic value of neonatal EEG following therapeutic hypothermia in survivors of hypoxic-ischemic encephalopathy

ObjectiveEarly prediction of neurological deficits following neonatal hypoxic-ischemic encephalopathy (HIE) may help to target support. Neonatal animal models suggest that recovery following hypoxia-ischemia depends upon cortical bursting. To test whether this holds in human neonates, we correlated the magnitude of cortical bursting during recovery (≥postnatal day 3) with neurodevelopmental outcomes.MethodsWe identified 41 surviving infants who received therapeutic hypothermia for HIE (classification at hospital discharge: 19 mild, 18 moderate, 4 severe) and had 9-channel electroencephalography (EEG) recordings as part of their routine care. We correlated burst power with Bayley-III cognitive, motor and language scores at median 24 months. To examine whether EEG offered additional prognostic information, we controlled for structural MRI findings.ResultsHigher power of central and occipital cortical bursts predicted worse cognitive and language outcomes, and higher power of central cortical bursts predicted worse motor outcome, all independently of structural MRI findings.ConclusionsClinical EEG after postnatal day 3 may provide additional prognostic information by indexing persistent active mechanisms that either support recovery or exacerbate brain damage, especially in infants with less severe encephalopathy.SignificanceThese findings could allow for the effect of clinical interventions in the neonatal period to be studied instantaneously in the future.     

EEG and ischemic stroke in full-term newborns]

The aims of this study were to describe EEG anomalies in unilateral neonatal ischemic stroke without hypoxic-ischemic encephalopathy, and to determine possible links between these abnormalities and long-term outcome. In 6 full-term newborns without severe fetal distress ischemic stroke was confirmed by computed tomography and/or magnetic resonance imaging. Twenty EEGs were recorded during the neonatal period, 5 in acute stage and 15 later. The duration of the follow-up ranged from 3 to 9 years. All newborns developed unilateral clonic seizures, right-sided (5 cases) or left-sided (1 case); seizures began between 14 and 48 h of life. At follow-up, 3 children were normal at 2 and 6 years of age, while the 3 others had sequelae: epilepsy at 9 years of age in one, and unilateral mild cerebral palsy in the 2 others (3 and 4 years of age), with behavioral problems in one of them. Critical EEG discharges, rhythmic sharp waves and/or slow waves were recorded on the injured side. Abnormalities of interictal activity were excess of alpha or theta rhythms, transitory EEG discontinuity or low voltage. The 2 children with cerebral palsy had numerous unilateral post-ictal positive rolandic slow sharp waves (PRSSWs), which were similar to the positive rolandic sharp waves of premature infants; the child with behavioral problems had numerous positive left-sided temporal fast sharp waves. PRSSWs could be associated with contralateral motor sequelae, while positive left temporal fast sharp waves were associated with long term behavioral problems. These findings may be used for future prospective studies aimed at specifying the relation between EEG abnormalities and long-term outcome.     

Development of epilepsy in newborns with moderate hypoxic-ischemic encephalopathy and neonatal seizures

Background: Hypoxic-ischemic encephalopathy (HIE) is one of the most frequent causes of neonatal death or neurological handicaps such as cerebral palsy, mental delay, and epilepsy. Moreover, an acute consequence of HIE are neonatal seizures which can cause an additional brain damage. The neurodevelopmental outcome is known in the mild or severe cases of HIE, but in the moderate conditions the predictivity results, to date, unsatisfying. Objective: The purpose of this prospective study was to appraise the development of post-neonatal epilepsy in a cohort of term infants with moderate HIE and neonatal seizures. Methods: This study considered all newborns admitted to Neonatal Intensive Care Unit of the University of Parma between January 2000 and December 2002 for perinatal asphyxia, then followed by Neonatal Neurology Service. In all patients, neonatal variables such as type of delivery, birth weight, gestational age, Apgar scores, the need for resuscitation and assisted ventilation soon after birth, and arterial-blood pH were analyzed. Results: Ninety-two newborns were enrolled in the study because of perinatal asphyxia. Of these, 27 subjects developed mild HIE, 25 moderate, and five severe HIE. Neonatal seizures were present in 13 subjects with moderate HIE and in all newborns with severe HIE. At the last follow-up, only three infants belonging to patients with severe HIE developed epilepsy. Conclusion: Moderate HIE seems not to be related to post-neonatal epilepsy either if associated or not with neonatal seizures.     

Prediction of short-term neurological outcome in full-term neonates with hypoxic-ischaemic encephalopathy based on combined use of electroencephalogram and neuro-imaging

BACKGROUND: In infants with hypoxic-ischaemic encephalopathy (HIE), prediction of the prognosis is based on clinical, neuro-imaging and neurophysiological parameters. METHODS: EEG, cranial ultrasound, MRI and follow-up findings of 23 infants (GA 35-42 weeks) with HIE were studied retrospectively to assess 1) the contribution of ultrasound, MRI and EEG in predicting outcome, 2) the accuracy of ultrasound as compared to MRI, and 3) whether patterns of brain damage and EEG findings are associated. RESULTS: An abnormal EEG background pattern was highly predictive of adverse outcome [positive predictive value (PPV) 0.88]. If combined with diffuse white and deep and/or cortical grey matter changes on ultrasound or MRI, the PPV increased to 1.00. Abnormal neuro-imaging findings were also highly predictive of adverse outcome. Abnormal signal intensity in the posterior limb of the internal capsule, and diffuse cortical grey matter damage were associated with adverse outcome. MRI showed deep grey matter changes more frequently than ultrasound. Severely abnormal neuro-imaging findings were always associated with abnormal EEG background pattern. CONCLUSIONS: Both early EEG and neuro-imaging findings are predictive of outcome in infants with HIE. The predictive value of EEG is strengthened by neuro-imaging.     

Prognostic value of the electroencephalogram in term and preterm infants following neonatal seizures

There is controversy in the literature regarding the prognostic value of the EEG following neonatal seizures. This report reviews the results of a prospective study comparing EEG findings and outcome in 74 term and preterm infants following neonatal seizures. EEGs were evaluated for both background rhythms and epileptiform activity. Outcome was evaluated at an average age of 33 months. Background rhythms were highly correlated with outcome. Low voltage, electrocerebral inactivity and burst suppression EEGs were associated with poor outcomes while normal EEGs were associated with favorable outcomes. Slow, maturationally delayed and asymmetrical EEGs were associated with variable outcomes. The presence of epileptiform activity on the EEG was correlated with adverse outcomes but was not as highly significant as background rhythms. Electroencephalographic seizures, whether associated with clinical manifestations or not, were highly correlated with poor outcomes. The significance of these EEG findings was similar in both term and preterm infants. The study demonstrates that the EEG is predictive of outcome following neonatal seizures.     

Prognostic value of neonatal discontinuous EEG

The burst suppression pattern on the neonatal electroencephalogram (EEG) is associated with a poor outcome. However, this serious abnormality constitutes only a small proportion of discontinuous neonatal EEGs. We sought to establish whether any easily measurable parameters among the broad range of excessively discontinuous neonatal EEGs are predictive of outcome. We retrospectively reviewed the EEGs and medical records of 43 term infants with excessively discontinuous EEGs. We quantitated 10 parameters in the bursts and interburst intervals, among them the predominant interburst interval duration (defined as the duration of more than 50% of all interburst intervals of an EEG). Univariate and multivariate analyses were performed on the 10 EEG variables in relation to neurologic outcome and subsequent epilepsy. Based on multivariate analysis, a single easily measurable EEG parameter related significantly to outcome. A predominant interburst interval duration of more than 30 seconds correlated with the occurrence of both unfavorable neurologic outcome and subsequent epilepsy (P = 0.040 and P = 0.033, respectively). In conclusion, a infant whose EEG contains a predominant interburst interval duration of more than 30 seconds has a 100% probability of experiencing severe neurologic disabilities or death and an 86% chance of developing subsequent epilepsy. This easily quantitated EEG parameter could be valuable for the early estimation of neurologic prognosis.     

Predictive value of sequential electroencephalogram (EEG) in neonates with seizures and its relation to neurological outcome

The aim of this study was to evaluate the relationship of sequential neonatal electroencephalography (EEG) and neurological outcome in neonates with seizures to identify polysomnographic features predictive of outcome. Sequential EEGs recordings of 58 neonates that belonged to 2 historical cohorts of newborns with seizures from the same neonatal intensive care unit and who had follow-up at the Neurodevelopment Clinic of the Hospital S?o Lucas, Pontifícia Universidade Católica do Rio Grande do Sul (PUCRS) in Porto Alegre, Brazil, were analyzed and classified into 4 groups: normal-normal, abnormal-normal, abnormal-abnormal, normal-abnormal. In patients with more than 2 recordings, during the neonatal period, the first EEG was compared with the following more abnormal. A total of 58 pairs of 2 sequential EEGs were analyzed. Considering the first EEG, a statistically significant difference was observed between the relationship of the result of this exam, if it was abnormal, with developmental delay (P = .030) and postnatal death (P = .030). Abnormal background activity was also related to neurodevelopment delay (P = .041). EEG sequences abnormal-abnormal and normal-abnormal significantly correlated to the outcome epilepsy ( P = .015). Abnormal sequential background activity was associated with neurodevelopment delay (P = .006) and epilepsy (P = .041). The burst suppression pattern when present in any EEG correlated with epilepsy (P = .013) and postnatal death (P = .034). Sequential abnormal background patterns in the first and second EEG increased the risk for epilepsy (relative risk [RR] = 1.8; 95% confidence interval [CI] = 1.03-3.0) and neurodevelopment delay (RR = 2.20; 95% CI = 1.3-3.0). Abnormal background activity only in the second electroencephalogram increased the risk for neurodevelopment delay (RR = 2.20; 95% CI = 1.3-3.0). All the neonates (n = 33) with seizures related to probable hypoxic ischemic encephalopathy had abnormalities in the first EEG (P = .030). Postnatal epilepsy was diagnosed in 24 infants (41.4%). Five (20.8%) presented West syndrome, 7 (29.2%) focal symptomatic epilepsy, 6 (25%) generalized symptomatic epilepsy, 2 (8.3%) early myoclonic encephalopathy, 1 (4.2%) early infantile epileptic encephalopathy, and in 3, the epileptic syndrome was undefined (12.5%). All infants (n = 5) with West syndrome had some degree of neurodevelopment delay. In conclusion, our findings suggest that sequential EEG in neonates with seizures has more predictive value to estimate the outcomes of neurodevelopment delay, epilepsy, and postnatal death than a single EEG recording. The abnormal background activity in even 1 EEG of the sequential recordings was more significant to determine neurological outcome than abnormal ictal activity or abnormalities in the organization of sleep state.     

Prolonged EEG depression in term and near-term infants with hypoxic ischemic encephalopathy and later development of West syndrome

Purpose: This study was performed to clarify the relationship between prolonged depression of electroencephalography (EEG) in term and near‐term infants with hypoxic ischemic encephalopathy (HIE) and the later development of West syndrome (WS). Methods: We investigated 17 term and near‐term infants with HIE. Inclusion criteria were as follows: ≥35 weeks of gestation, clinical signs of HIE, magnetic resonance imaging (MRI) lesions corresponding to HIE, assessment of outcome at >18 months of age, depression of EEG, and serial EEG examinations. The 17 infants were divided into the following two groups: Group A (n = 4) with prolonged EEG depression over 21 days of age, and group B (n = 13) with disappearance of EEG depression by 21 days of age. Results: WS developed in all four infants in group A, but in only one of 13 infants in group B. WS occurred significantly more frequently in group A than in group B. For the prediction of subsequent development of WS, prolonged EEG depression over 21 days of age showed sensitivity of 0.80 and specificity of 1.0. In both groups, abnormal irregular faster waves with or without EEG depression were seen in 11 infants between 2 and 28 days of age. They had no significant relationship with WS, but were significantly related to an adverse developmental outcome. Conclusions: Prolonged depression of EEG over 21 days of age in term or near‐term infants with HIE is a valuable predictor of the later development of WS.     

Perinatal brain injuries and subsequent epilepsy: a study on intraventricular hemorrhage in preterm infants and hypoxic-ischemic encephalopathy in full-term infants

The clinical course of symptomatic epilepsy caused by intraventricular hemorrhage (IVH) in 7 preterm infants and hypoxic-ischemic encephalopathy (HIE) in 9 full-term infants were followed up for more than 2 years and 6 months. West syndrome was the first manifestation of epilepsy in 10 cases (IVH: 4, HIE: 6), and all 16 patients had severe neuropsychiatric deficits. Comparing with children without epilepsy, IVH grades III and IV, mechanical ventilation for more than 6 days and neonatal convulsions in the patients with IVH, and mechanical ventilation and neonatal convulsions in the patients with HIE, were significantly related to the risk of subsequent epilepsy. These findings suggest that the degree of brain injuries may be predictive of the development of epilepsy during infancy and early childhood in the patients with IVH or HIE.