COMPUTATIONAL INTELLIGENCE, Issue 2 2005
Ning Zhong
E-science is about global collaboration in key areas of science such as cognitive science and brain science, and the next generation of infrastructure such as the Wisdom Web and Knowledge Grids. As a case study, we investigate human multiperception mechanism by cooperatively using various psychological experiments, physiological measurements, and data mining techniques for developing artificial systems which match human ability in specific aspects. In particular, we observe fMRI (functional magnetic resonance imaging) and EEG (electroencephalogram) brain activations from the viewpoint of peculiarity oriented mining and propose a way of peculiarity oriented mining for knowledge discovery in multiple human brain data. Based on such experience and needs, we concentrate on the architectural aspect of a brain-informatics portal from the perspective of the Wisdom Web and Knowledge Grids. We describe how to build a data-mining grid on the Wisdom Web for multiaspect human brain data analysis. The proposed methodology attempts to change the perspective of cognitive scientists from a single type of experimental data analysis toward a holistic view at a long-term, global field of vision. [source]

Altered interaction between cardiac vagal influence and delta sleep EEG suggests an altered neuroplasticity in patients suffering from major depressive disorder

ACTA PSYCHIATRICA SCANDINAVICA, Issue 3 2010
F. Jurysta
Jurysta F, Kempenaers C, Lancini J, Lanquart J-P, van de Borne P, Linkowski P. Altered interaction between cardiac vagal influence and delta sleep EEG suggests an altered neuroplasticity in patients suffering from major depressive disorder. Objective:, Major depressive disorder (MDD), which is associated with altered neuroplasticity and increased relative cardiac sympathic activity, enhances the risk of cardiovascular pathologies. Interaction between cardiac sympatho-vagal indexes and delta sleep power is probably altered in MDD. Method:, Sleep characteristics and cardiac sympatho-vagal indexes of 10 depressive patients were compared to 10 control men across the first three non-rapid eye movement (NREM),REM cycles. Interaction between normalized high frequency (HF) and delta power bands was studied using coherence analysis. Results:, Patients showed increased sleep latency, stage 1 and wake durations. No differences in heart rate variabilities were observed: Total power, HF and RR-interval decreased from NREM to REM sleep and wakefulness in both groups. Gain value was lower in patients while coherence and phase shift were similar between groups. Modifications in HF appear 8 min before modifications in delta. Conclusion:, Major depressive disorder is related to an altered link between cardiac vagal influence and delta sleep, suggesting disorders in cardiovascular controls and an altered neuroplasticity. [source]

Seizures and paroxysmal events: symptoms pointing to the diagnosis of pyridoxine-dependent epilepsy and pyridoxine phosphate oxidase deficiency

DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 7 2010
BERNHARD SCHMITT
Aim, We report on seizures, paroxysmal events, and electroencephalogram (EEG) findings in four female infants with pyridoxine-dependent epilepsy (PDE) and in one female with pyridoxine phosphate oxidase deficiency (PNPO). Method, Videos and EEGs were analysed and compared with videos of seizures and paroxysmal events archived from 140 neonates. PDE and PNPO were proven by complete control of seizures once pyridoxine or pyridoxal 5,-phosphate was administered and by recurrence when withdrawn. Mutations in the antiquitin gene were found in three patients and in the PNPO gene in one child. Results, Seizures began within 48 hours after birth in four newborns and at age 3 weeks in one. Frequent multifocal and generalized myoclonic jerks, often intermixed with tonic symptoms, abnormal eye movement, grimacing, or irritability, were observed in all infants with PDE and PNPO, but rarely in the other archived videos of neonates. EEGs were inconstant and frequently no discernable ictal changes were recorded during the seizures and the paroxysmal events. In addition, interictal EEGs were inconclusive, with normal and abnormal recordings. In older children tonic,clonic seizures, abnormal behaviour, inconsolable crying, frightened facial expression, sleep disturbance, loss of consciousness, paraesthesia, or intermittent visual symptoms were described during controlled and uncontrolled withdrawal or insufficient dosage. Interpretation, PDE or PNPO should be considered in infants with prolonged episodes of mixed multifocal myoclonic tonic symptoms, notably when associated with grimacing and abnormal eye movements. [source]

Academic performance in children with rolandic epilepsy

DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 5 2008
P Piccinelli MD
The aim of this study was to investigate the frequency of reading, writing, and calculation disabilities in children with typical rolandic epilepsy (RE) and healthy control children. We also aimed to define the possible electroclinical markers of specific cognitive dysfunctions in RE. School abilities were evaluated and compared in 20 children (eight males, 12 females; mean age 10y 3mo [SD 1y 7mo]; range 7y 9mo-12y 9mo) consecutively diagnosed with typical RE, and a group of 21 healthy controls (nine males, 12 females; mean age 10y 4mo [SD 1y 8mo]; range 7y 6mo-13y 3mo). All the children received standardized neuropsychological tests. For each patient an exhaustive seizure diary was kept and all the sleep electroencephalogram (EEG) recordings were reviewed. Specific difficulties with reading, writing, and calculation (diagnosed according to the criteria of the Diagnostic and Statistical Manual of Mental Disorders, 4th edition) were found in nine out of 20 children with RE and two out of 21 healthy controls (,2=0.01). The specific learning disabilities in the RE group were correlated with a marked increase in epileptiform discharges during sleep (,2=0.02) and an early onset of epilepsy (,2=0.02). Our findings suggest that seizure onset before age 8 years and epileptiform discharges (more than 50% of the sleep EEG recording) in several tracings over more than a year are relevant markers for identifying patients at risk of developing academic difficulties. [source]

Interobserver reliability of visual interpretation of electroencephalograms in children with newly diagnosed seizures

DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 5 2006
Hans Stroink MD
The reliability of visual interpretation of electroencephalograms (EEG) is of great importance in assessing the value of this diagnostic tool. We prospectively obtained 50 standard EEGs and 61 EEGs after partial sleep deprivation from 93 children (56 males, 37 females) with a mean age of 6 years 10 months (SE 5mo; range 4mo,15y 7mo) with one or more newly diagnosed, unprovoked seizures. Two clinical neurophysiologists independently classified the background pattern and the presence of epileptiform discharges or focal non-epileptiform abnormalities of each EEG. The agreement was substantial for the interpretation of the EEG as normal or abnormal (kappa 0.66), almost perfect for the presence of epileptiform discharges (kappa 0.83), substantial for the occurrence of an abnormal background pattern (kappa 0.73), and moderate for the presence of focal non-epileptiform discharges (kappa 0.54). In conclusion, the reliability of the visual interpretation of EEGs in children is almost perfect as regards the presence of epileptiform abnormalities, and moderate to substantial for the presence of other abnormalities. [source]

Sturge,Weber syndrome and paroxysmal hemiparesis: epilepsy or ischaemia?

DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 11 2004
Floor E Jansen MD
Transient neurological deficits experienced by patients with Sturge,Weber syndrome can be caused by epilepsy, or may result from temporary ischaemia of the cortex underlying the vascular malformation. To show the difficulty in distinguishing seizures from ischaemic symptoms, two male children with episodes of acute unilateral weakness are presented here as well as a review of the literature. The first child presented at 2 years of age with a sudden increase in his pre-existing right hemiparesis accompanied by screaming. Ictal epileptiform activity was recorded at the moment of the attack, and subsequent seizures were controlled by adjustment of antiepileptic drug treatment. The second child presented at 4 years of age with attacks of vomiting and a coinciding increase in the pre-existing paresis of the left leg. Electroencephalogram (EEG) recording did not show ictal epileptiform activity. The origin was presumed to be vascular. Treatment with aspirin led to control of these transient ischaemic attacks. Ictal EEG is needed to differentiate between an epileptic and an ischaemic origin of transient focal deficit. Treatment with aspirin should be considered if an ischaemic origin cannot be excluded. [source]

Toward a better understanding of the pathophysiology of OCD SSRI responders: QEEG source localization

ACTA PSYCHIATRICA SCANDINAVICA, Issue 3 2007
T. G. Bolwig
Objective:, To demonstrate the utility of three-dimensional source localization of the scalp-recorded electroencephalogram (EEG) for the identification of the most probable underlying brain dysfunction in patients with obsessive,compulsive disorder (OCD). Method:, Eyes-closed resting EEG data was recorded from the scalp locations of the International 10/20 System. Variable resolution electromagnetic tomography (VARETA) was applied to artifact-free EEG data. This mathematical algorithm estimates the source generators of EEG recorded from the scalp. Results:, An excess in the alpha range was found with sources in the corpus striatum, in the orbito-frontal and temporo-frontal regions in untreated OCD patients. This abnormality was seen to decrease following successful treatment with paroxetine. Conclusion:, The VARETA findings of an activation/deactivation pattern in cortical and subcortical structures in paroxetine-responsive patients are in good accordance with data obtained in previously published positron emission tomography studies related to current hypotheses of a thalamo-striatal-frontal feedback loop being relevant for understanding the pathophysiology of OCD. [source]

Developmental outcome and types of chronic-stage EEG abnormalities in preterm infants

DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 11 2002
Akihisa Okumura MD
The aims of this study were to determine the types of chronic-stage EEG abnormalities that exist and to clarify their relation to neurodevelopmental outcome in preterm infants. We evaluated 183 preterm infants with gestational ages of less than 33 weeks (mean age 29.2 weeks) and weighing less than 2000g (mean weight 1275g). The first EEG was performed within 72 hours of life; thereafter, EEG was performed once every 1 to 4 weeks until the infant reached a post-conceptional age of 40 to 42 weeks. Two kinds of EEG abnormalities, acute- and chronic-stage abnormalities, were evaluated and we assessed mainly the latter. Chronic-stage EEG abnormalities were divided into two patterns: disorganized and dysmature. Periventricular leukomalacia (PVL) and intraventricular haemorrhage (IVH) were diagnosed on the basis of ultrasound findings. Psychomotor development was examined every 3 months after discharge until at least 18 months of the infants'corrected age. Disorganized and dysmature patterns were observed in 52 and 28 infants respectively. Among the 52 infants with disorganized patterns, PVL was observed in 31 and IVH in seven infants. Thirty-nine infants had cerebral palsy (CP). Twenty-six achieved normal cognitive development. Of the 28 infants with dysmature patterns, PVL was seen in one and IVH in 11 infants. CP was seen in five infants. Only eight infants achieved normal cognitive development. Gestational age and birth weight were significantly lower in infants with dysmature patterns than in those with disorganized ones. Results indicate that types of chronic-stage EEG abnormalities are related to types of neurological sequelae and are useful for assessing the mode of brain injury in preterm infants. [source]

Stability of resting frontal electroencephalogram (EEG) asymmetry and cardiac vagal tone in adolescent females exposed to child maltreatment

DEVELOPMENTAL PSYCHOBIOLOGY, Issue 6 2009
Vladimir Miskovic
Abstract The experience of child maltreatment is a known risk factor for the development of psychopathology. Structural and functional modifications of neural systems implicated in stress and emotion regulation may provide one mechanism linking early adversity with later outcome. The authors examined two well-documented biological markers of stress vulnerability [resting frontal electroencephalogram (EEG) asymmetry and cardiac vagal tone] in a group of adolescent females exposed to child maltreatment (n,=,38; M age,=,14.47) and their age-matched non-maltreated (n,=,25; M age,=,14.00) peers. Maltreated females exhibited greater relative right frontal EEG activity and lower cardiac vagal tone than controls over a 6-month period. In addition, frontal EEG asymmetry and cardiac vagal tone remained stable in the maltreated group across the 6 months, suggesting that the neurobiological correlates of maltreatment may not simply reflect dynamic, short-term changes but more long lasting alterations. The present findings appear to be the first to demonstrate stability of two biologically based stress-vulnerability measures in a maltreated population. Findings are discussed in terms of plasticity within the neural circuits of emotion regulation during the early childhood period and alternative causal models of developmental psychopathology. © 2009 Wiley Periodicals, Inc. Dev Psychobiol 51: 474,487, 2009 [source]

The effects of age and sex on mental rotation performance, verbal performance, and brain electrical activity

DEVELOPMENTAL PSYCHOBIOLOGY, Issue 4 2002
Jonathan E. Roberts
Abstract This study examined the effects of age and sex on mental rotation performance, verbal performance, and brain-wave activity. Thirty-two 8-year-olds (16 boys) and 32 college students (16 men) had EEG recorded at baseline and while performing four computerized tasks: a two-dimensional (2D) gingerbread man mental rotation, a 2D alphanumeric mental rotation, of three-dimensional (3D) basketball player mental rotation, and lexical decision making. Additionally, participants completed a paper- and pencil water level task and an oral verbal fluency task. On the 2D alphanumeric and 3D basketball player mental rotation tasks, men performed better than boys, but the performance of women and girls did not differ. On the water level task, men performed better than women whereas there was no difference between boys and girls. No sex differences were found on the 2D gingerbread man mental rotation, lexical decision-making, and verbal fluency tasks. EEG analyses indicated that men exhibited left posterior temporal activation during the 2D alphanumeric task and that men and boys both exhibited greater left parietal activation than women and girls during the 2D gingerbread man task. On the 3D basketball player mental rotation task, all participants exhibited greater activation of the right parietal area than the left parietal area. These data give insight into the brain activity and cognitive development changes that occur between childhood and adulthood. © 2002 Wiley Periodicals, Inc. Dev Psychobiol 40: 391,407, 2002. Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/dev.10039 [source]

Age-related changes in transient and oscillatory brain responses to auditory stimulation during early adolescence

DEVELOPMENTAL SCIENCE, Issue 2 2009
Catherine Poulsen
Maturational changes in the capacity to process quickly the temporal envelope of sound have been linked to language abilities in typically developing individuals. As part of a longitudinal study of brain maturation and cognitive development during adolescence, we employed dense-array EEG and spatiotemporal source analysis to characterize maturational changes in the timing of brain responses to temporal variations in sound. We found significant changes in the brain responses compared longitudinally at two time points in early adolescence, namely 10 years (65 subjects) and 11.5 years (60 of the 65 subjects), as well as large differences between adults, studied with the same protocol (Poulsen, Picton & Paus, 2007), and the children at 10 and 11.5 years of age. The transient auditory evoked potential to tone onset showed decreases in the latency of vertex and T-complex components, and a highly significant increase in the amplitude of the N1 wave with increasing age. The auditory steady state response to a 40-Hz frequency-modulated tone increased in amplitude with increasing age. The peak frequency of the envelope-following response to sweeps of amplitude-modulated white noise also increased significantly with increasing age. These results indicate persistent maturation of the cortical mechanisms for auditory processing from childhood into middle adulthood. [source]

Role of neurophysiology in the clinical practice of primary pediatric headaches

DRUG DEVELOPMENT RESEARCH, Issue 7 2007
V. Raieli
Abstract The role of electrophysiological studies in pediatric headaches is controversial. In childhood headaches, neurophysiological examinations are of interest for potential clinical use because they are noninvasive and are scarcely influenced by environmental factors or drug use. Electrophysiological studies in childhood headache principally explored the role of electroencephalographic (EEG) evaluations in migraine, while less evidence has been reported about other neurophysiological techniques, such as evoked potentials, event-related potentials, and, less often, transcranial magnetic stimulation. In this brief review, we point out our attention to the aid of neurophysiological methods in the clinical diagnosis of pediatric headaches. Although many examinations are actually of little value in the clinical setting, they may have a potential role in some clinical subgroups or in monitoring and evaluating the effects of pharmacological treatment. Drug Dev Res 68:389,396, 2007. © 2008 Wiley-Liss, Inc. [source]

Relationship between biotic ligand model-based water quality criteria and avoidance and olfactory responses to copper by fish

ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 9 2010
Joseph S. Meyer
Abstract The U.S. Environmental Protection Agency's (U.S. EPA) water quality criteria for Cu were tested to determine whether they protect fish against neurophysiological impairment. From published studies with rainbow trout (Oncorhynchus mykiss), Chinook salmon (Oncorhynchus tshawytscha), coho salmon (Oncorhynchus kisutch), and fathead minnows (Pimephales promelas), 20% inhibition concentrations (IC20s) were calculated for avoidance of Cu-containing water and for impairment of electroencephalogram (EEG) and electro-olfactogram (EOG) responses to natural odorants in Cu-containing water. Additionally, a Cu-olfactory biotic ligand model (BLM) that fits the coho salmon EOG data was parameterized by changing the sensitivity parameter in the ionoregulatory-based BLM. The IC20s calculated from reported Cu avoidance, EEG, and EOG data and IC20s predicted by the olfactory BLM were compared with acute and chronic Cu criteria calculated using U.S. EPA's BLM 2007 or hardness-adjustment equations. The BLM-based chronic criteria were protective in all 16 exposure water,species combinations used in avoidance and olfaction experiments. Additionally, the BLM-based acute criteria were protective in all 11 exposure water,species combinations in which comparisons could be made with olfactory BLM-predicted IC20s but not in two of the 16 exposure water,species combinations in which comparisons could be made with the reported IC20s (which were ,8% lower than but did not differ significantly from the BLM-based acute criteria; p,>,0.05). In effect, the olfactory BLM factored out the relatively high variability in the reported IC20s. It is concluded that the U.S. EPA's BLM-based water quality criteria for Cu protect against these types of neurophysiological impairment in the six species,endpoint combinations analyzed in this paper. However, the U.S. EPA's hardness-based criteria for Cu sometimes were considerably underprotective and sometimes were much less protective than the BLM-based criteria. Environ. Toxicol. Chem. 2010;29:2096,2103. © 2010 SETAC [source]

Impact of severe epilepsy on development: Recovery potential after successful early epilepsy surgery

EPILEPSIA, Issue 7 2010
Eliane Roulet-Perez
Summary Purpose:, Epilepsy surgery in young children with focal lesions offers a unique opportunity to study the impact of severe seizures on cognitive development during a period of maximal brain plasticity, if immediate control can be obtained. We studied 11 children with early refractory epilepsy (median onset, 7.5 months) due to focal lesion who were rendered seizure-free after surgery performed before the age of 6 years. Methods:, The children were followed prospectively for a median of 5 years with serial neuropsychological assessments correlated with electroencephalography (EEG) and surgery-related variables. Results:, Short-term follow-up revealed rapid cognitive gains corresponding to cessation of intense and propagated epileptic activity [two with early catastrophic epilepsy; two with regression and continuous spike-waves during sleep (CSWS) or frontal seizures]; unchanged or slowed velocity of progress in six children (five with complex partial seizures and frontal or temporal cortical malformations). Longer-term follow-up showed stabilization of cognitive levels in the impaired range in most children and slow progress up to borderline level in two with initial gains. Discussion:, Cessation of epileptic activity after early surgery can be followed by substantial cognitive gains, but not in all children. In the short term, lack of catch-up may be explained by loss of retained function in the removed epileptogenic area; in the longer term, by decreased intellectual potential of genetic origin, irreversible epileptic damage to neural networks supporting cognitive functions, or reorganization plasticity after early focal lesions. Cognitive recovery has to be considered as a "bonus," which can be predicted in some specific circumstances. [source]

Model of cryptogenic infantile spasms after prenatal corticosteroid priming

EPILEPSIA, Issue 2010
Libor Velí
Summary Infantile spasms (IS) is a devastating epilepsy syndrome of childhood. IS occurs in 3,12-month-old infants and is characterized by spasms, interictal electroencephalography (EEG) hypsarrhythmia, and profound mental retardation. Hormonal therapy [adrenocorticotropic hormone (ACTH), corticosteroids] is frequently used, but its efficacy is tainted by severe side effects. For research of novel therapies, a validated animal model of IS is required. We propose the model of spastic seizures triggered by N -methyl- d -aspartate (NMDA) in infant rats prenatally exposed to betamethasone. The spasms have remarkable similarity to human IS, including motor flexion spasms, ictal EEG electrodecrement, and responsiveness to ACTH. Interestingly, the spasms do not involve the hippocampus. Autoradiographic metabolic mapping as well as tagging of the areas of neuronal excitation with c-fos indicates a strong involvement of hypothalamic structures such as the arcuate nucleus, which has significant bilateral connections with other hypothalamic nuclei as well as with the brainstem. [source]

Bispectral Electroencephalographic Analysis of Patients Undergoing Procedural Sedation in the Emergency Department

ACADEMIC EMERGENCY MEDICINE, Issue 6 2003
James R. Miner MD
Abstract Objective: To determine whether there is a correlation between the level of sedation achieved during procedural sedation (PS) in the emergency department as determined by bispectral electroencephalographic (EEG) analysis (BIS) and the rate of respiratory depression (RD), the patient's perception of pain, recall of the procedure, and satisfaction. Methods: This was a prospective observational study conducted in an urban county hospital of adult patients undergoing PS using propofol, methohexital, etomidate, and the combination of fentanyl and midazolam. Consenting patients were monitored by vital signs, pulse oximetry, nasal-sample end-tidal carbon dioxide (ETCO2), and BIS monitors during PS. Respiratory depression (RD) was defined as an oxygen saturation <90%, a change from baseline ETCO2 of >10 mm Hg, or an absent ETCO2 waveform at any time during the procedure. After the procedure, patients were asked to complete three 100-mm visual analog scales (VASs) concerning their perception of pain, recall of the procedure, and satisfaction with the procedure. Patients were divided into four groups based on the lowest BIS score recorded during the procedure, group 1, >85; group 2, 70,85; group 3, 60,69; group 4, <60. Rates of RD and VAS outcomes were compared between groups using chi-square statistics. Results: One hundred eight patients were enrolled in the study. No serious adverse events were noted. RD was seen in three of 14 (21.4%) of the patients in group 1, seven of 34 (20.6%) in group 2, 16 of 26 (61.5%) in group 3, and 18 of 34 (52.9%) in group 4. The rate of RD in patients in group 2 was not significantly different from that in group 1 (p = 0.46). The rate of RD in group 2 was significantly lower than that in groups 3 (p = 0.0003) and 4 (p = 0.006). For the VAS data, when group 1 was compared with the combined groups 2, 3, and 4, it had significantly higher rates of pain (p = 0.003) and recall (p = 0.001), and a dissatisfaction rate (p = 0.085) that approached significance. When groups 2, 3, and 4 were compared with chi-square test, there was not a significant difference in pain (p = 0.151), recall (p = 0.27), or satisfaction (p = 0.25). Conclusions: Patients with a lowest recorded BIS score between 70 and 85 had the same VAS outcomes as more deeply sedated patients and the same rate of RD as less deeply sedated patients. This range of scores represented the optimally sedated patients in this study. [source]

De novo epileptic confusion in the elderly: A 1-year prospective study

EPILEPSIA, Issue 6 2010
Olivier Veran
Summary Purpose:, Nonconvulsive status epilepticus (NCSE) is clinically difficult to diagnose, especially in old patients without epilepsy, and requires electroencephalography (EEG) for diagnosis. Its incidence among elderly patients with confusion of unknown origin (CUO) remains undetermined. Methods:, A 1-year prospective study was conducted in patients aged 60 years or older, for whom EEG was requested because of confusion considered to be of unknown origin after initial clinical, biologic, and imaging investigations. Diagnosis criteria included a validated clinical assessment scale to confirm confusion. Results:, Of 44 patients with confirmed CUO, 7 presented with de novo NCSE. NCSE population had a mean age of 76 years (range, 60,97 years). No statistically significant differences were found between NCSE patients and others for age, drugs, presence of myoclonia, eyelid myoclonia, tachycardia, or agitation. In contrast, an acute onset (<24 h), gender (100% female among NCSE patients), and lack of clinical response to simple commands were significantly associated with NCSE. No differences between the two groups were evidenced for mortality and morbidity (length of hospitalization, social outcome, and so on). Discussion:, Almost 16% of patients aged 60 or older with confusion of unknown origin had NCSE, according to this first prospective study. Female patients with rapid onset (<24 h) of symptoms and lack of response to simple commands were at a higher risk of presenting with NCSE. [source]

Type 1 diabetes and epilepsy: Efficacy and safety of the ketogenic diet

EPILEPSIA, Issue 6 2010
Anastasia Dressler
Summary Diabetes type 1 seems to be more prevalent in epilepsy, and low-carbohydrate diets improve glycemic control in diabetes type 2, but data on the use of the classic ketogenic diet (KD) in epilepsy and diabetes are scarce. We present 15 months of follow-up of a 3 years and 6 months old girl with diabetes type 1 (on the KD), right-sided hemiparesis, and focal epilepsy due to a malformation of cortical development. Although epileptiform activity on electroencephalography (EEG) persisted (especially during sleep), clinically overt seizures have not been reported since the KD. An improved activity level and significant developmental achievements were noticed. Glycosylated hemoglobin (HbA1c) levels improved, and glycemic control was excellent, without severe side effects. Our experience indicates that diabetes does not preclude the use of the KD. [source]

Electrical source imaging for presurgical focus localization in epilepsy patients with normal MRI

EPILEPSIA, Issue 4 2010
Verena Brodbeck
Summary Purpose:, Patients with magnetic resonance (MR),negative focal epilepsy (MRN-E) have less favorable surgical outcomes (between 40% and 70%) compared to those in whom an MRI lesion guides the site of surgical intervention (60,90%). Patients with extratemporal MRN-E have the worst outcome (around 50% chance of seizure freedom). We studied whether electroencephalography (EEG) source imaging (ESI) of interictal epileptic activity can contribute to the identification of the epileptic focus in patients with normal MRI. Methods:, We carried out ESI in 10 operated patients with nonlesional MRI and a postsurgical follow-up of at least 1 year. Five of the 10 patients had extratemporal lobe epilepsy. Evaluation comprised surface and intracranial EEG monitoring of ictal and interictal events, structural MRI, [18F]fluorodeoxyglucose positron emission tomography (FDG-PET), ictal and interictal perfusion single photon emission computed tomography (SPECT) scans. Eight of the 10 patients also underwent intracranial monitoring. Results:, ESI correctly localized the epileptic focus within the resection margins in 8 of 10 patients, 9 of whom experienced favorable postsurgical outcomes. Discussion:, The results highlight the diagnostic value of ESI and encourage broadening its application to patients with MRN-E. If the surface EEG contains fairly localized spikes, ESI contributes to the presurgical decision process. [source]

Interictal EEG spikes identify the region of electrographic seizure onset in some, but not all, pediatric epilepsy patients

EPILEPSIA, Issue 4 2010
Eric D. Marsh
Summary Purpose:, The role of sharps and spikes, interictal epileptiform discharges (IEDs), in guiding epilepsy surgery in children remains controversial, particularly with intracranial electroencephalography (IEEG). Although ictal recording is the mainstay of localizing epileptic networks for surgical resection, current practice dictates removing regions generating frequent IEDs if they are near the ictal onset zone. Indeed, past studies suggest an inconsistent relationship between IED and seizure-onset location, although these studies were based upon relatively short EEG epochs. Methods:, We employ a previously validated, computerized spike detector to measure and localize IED activity over prolonged, representative segments of IEEG recorded from 19 children with intractable, mostly extratemporal lobe epilepsy. Approximately 8 h of IEEG, randomly selected 30-min segments of continuous interictal IEEG per patient, were analyzed over all intracranial electrode contacts. Results:, When spike frequency was averaged over the 16-time segments, electrodes with the highest mean spike frequency were found to be within the seizure-onset region in 11 of 19 patients. There was significant variability between individual 30-min segments in these patients, indicating that large statistical samples of interictal activity were required for improved localization. Low-voltage fast EEG at seizure onset was the only clinical factor predicting IED localization to the seizure-onset region. Conclusions:, Our data suggest that automated IED detection over multiple representative samples of IEEG may be of utility in planning epilepsy surgery for children with intractable epilepsy. Further research is required to better determine which patients may benefit from this technique a priori. [source]

Anoxia,ischemia: A mechanism of seizure termination in ictal asystole

EPILEPSIA, Issue 1 2010
Stephan U. Schuele
Summary Cerebral anoxia,ischemia (CAI) is a potent inhibitor of cerebral hyperactivity and a potential mechanism of seizure self-termination. Prolonged ictal asystole (IA) invariably leads to CAI and has been implicated as a potential cause of sudden unexplained death in epilepsy (SUDEP). IA was seen in eight consecutive patients (0.12% of all patients monitored). Ten of their seizures with IA had evidence of CAI on electroencephalography (EEG), manifested by bilateral hypersynchronous slowing (BHS), and were compared to 18 seizures without signs of CAI. The ictal EEG pattern resolved in all 10 CAI events with onset of the BHS. The period from IA onset to seizure end was reduced in events with BHS compared to events without BHS (10.5 s vs. 28.3 s, respectively; p = 0.005), and the total seizure duration tended to be shorter. Anoxia,ischemia as a result of IA may represent an effective endogenous mechanism for seizure termination and may explain why the hearts of patients with ictal asystole reported to date in the literature resumed beating spontaneously. [source]

Evidence of shared genetic risk factors for migraine and rolandic epilepsy

EPILEPSIA, Issue 11 2009
Tara Clarke
Summary Purpose:, Evidence for a specific association between migraine and rolandic epilepsy (RE) has been conflicting. Children with migraine frequently have electroencephalographic (EEG) abnormalities, including rolandic discharges, and approximately 50% of siblings of patients with RE exhibit rolandic discharges. We assessed migraine risk in RE probands and their siblings. Methods:, We used cohort and reconstructed cohort designs to respectively assess the relative risk of migraine in 72 children with RE and their 88 siblings using International Classification of Headache Disorders (ICHD-2) criteria. Incidences were compared in 150 age and geographically matched nonepilepsy probands and their 188 siblings. We used a Cox proportional hazards model, using age as the time base, adjusting hazard ratios (HRs) for sex in the proband analysis, and for sex and proband migraine status in the sibling analysis. Results:, Prevalence of migraine in RE probands was 15% versus 7% in nonepilepsy probands, and in siblings of RE probands prevalence was 14% versus 4% in nonepilepsy siblings. The sex-adjusted HR of migraine for an RE proband was 2.46 [95% confidence interval (CI) 1.06,5.70]. The adjusted HR of having ,1 sibling with migraine in an RE family was 3.35 (95% CI 1.20,9.33), whereas the HR of any one sibling of a RE proband was 2.86 (95% CI 1.10,7.43). Discussion:, Migraine is strongly comorbid in RE and independently clusters in their siblings. These results suggest shared susceptibility to migraine and RE that is not directly mediated by epileptic seizures. Susceptibility gene variants for RE may be tested as risk factors for migraine. [source]

Extent of initial injury determines language lateralization in mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS)

EPILEPSIA, Issue 10 2009
Chaturbhuj Rathore
Summary Purpose:, To assess the prevalence and attributes of atypical language lateralization (ALL) in patients with left mesial temporal lobe epilepsy associated with hippocampal sclerosis (MTLE-HS). Methods:, We recruited consecutive patients with left MTLE-HS, who had undergone resective surgery and had pathologically proven HS. Based on the Wada test, language lateralization was classified into typical (left hemispheric) or atypical (right hemispheric or codominant). We assessed the attributes of patients with ALL using univariate and multivariate analyses. Results:, Of 124 patients with left MTLE-HS, 23 (18.5%) had ALL. ALL occurred more frequently in patients with severe initial precipitating injury (IPI), early onset of epilepsy, and a short latent period between IPI and onset of habitual seizures. ALL was more common in patients with bitemporal and extratemporal interictal epileptiform discharges (IEDs) on electroencephalogram (EEG) and extratemporal changes on magnetic resonance imaging (MRI). On multivariate analyses, the age at onset of habitual seizures <6 years, atypical IPI, nonunilateral temporal IEDs, and extratemporal MRI abnormalities independently predicted ALL. The likelihood of ALL was very low (,1%) when all of these four risk factors were absent, whereas it was very high (>95%), if any three or all four of them were present. Conclusions:, ALL occurs in one-fifth of patients with left MTLE-HS. ALL is more frequent in those with structural or functional extrahippocampal involvement and early onset of epilepsy interrupting the development of normal language networks. Because ALL is uncommon in those with damage/dysfunction restricted to the hippocampus, the hippocampus itself may have only a limited role in determining language lateralization. [source]

Temporal distribution of clinical seizures over the 24-h day: A retrospective observational study in a tertiary epilepsy clinic

EPILEPSIA, Issue 9 2009
Wytske A. Hofstra
Summary Purpose:, Very few studies have evaluated seizure occurrence in humans over the 24-h day; data from children are particularly scarce. Circadian patterns in seizure occurrence may be of importance in epilepsy research and may have important implications in diagnosis and therapy. Methods:, We have analyzed clinical seizures of 176 consecutive patients (76 children, 100 adults) who had continuous electroencephalography (EEG) and video monitoring lasting more than 22 h. Several aspects of seizures were noted, including classification, time of day, origin, and sleep stage. Results:, More than 800 seizures were recorded. Significantly more seizures were observed from 11:00 to 17:00 h, and from 23:00 to 05:00 h significantly fewer seizures were seen. The daytime peak incidences were observed in seizures overall, complex partial seizures (in children and adults), seizures of extratemporal origin (in children), and seizures of temporal origin (in adults). Incidences significantly lower than expected were seen in the period 23:00 to 05:00 h in seizures overall, complex partial seizures (in children and adults), and in tonic seizures (in children). In addition, significantly fewer seizures of temporal (in children and adults) and extratemporal origin (in children) were observed in this period. Discussion:, The results suggest that certain types of seizures have a strong tendency to occur in true diurnal patterns. These patterns are characterized by a peak during midday and a low in the early night. [source]

Interobserver agreement in neonatal seizure identification

EPILEPSIA, Issue 9 2009
Aileen Malone
Summary Objectives:, Accurate diagnosis of neonatal seizures is critically important and is often made clinically, without EEG (electroencephalography) monitoring. This observational study aimed to determine the accuracy and interobserver reliability of healthcare professionals in distinguishing clinically manifested seizures from other neonatal movements, when presented with clinical histories and digital video recordings only. Methods:, Twenty digital video recordings of paroxysmal movements in term and preterm infants were selected from a video-EEG database. The movements were categorized as seizure and nonseizure using EEG. Health care professionals (n = 137) from eight neonatal intensive care units (NICUs) were shown the video recordings with additional relevant clinical data, excluding EEG findings. The observers were asked to indicate which movements they considered to be seizure or nonseizure. A multirater Kappa statistic was used to assess agreement between observers and with the true diagnosis. Results:, Twenty video clips (11 seizure, 9 nonseizure) were evaluated by 91 doctors and 46 other professionals. The average number of correctly identified events was 10/20. Clonic seizures were correctly identified most frequently (range 36.5,95.6% of observers). Subtle seizures were poorly identified (range 20.4,49.6% of observers). The interobserver agreement (Kappa) for doctors and other health care professionals was poor at 0.21 and 0.29, respectively. Agreement with the correct diagnosis was also poor at 0.09 for doctors and ,0.02 for other healthcare professionals. Discussion:, It is often impossible to accurately differentiate between seizure-related and nonseizure movements in infants using clinical evaluation alone. In addition, doctors do not have a higher capacity for discriminating between neonatal paroxysmal events than other health care professionals. Until reliable continuous neurologic monitoring of newborn babies is available, it is likely that some babies with seizures will remain undetected and others with nonseizure movements will continue to be treated with potentially harmful anticonvulsants. [source]

Coexistence of symptomatic focal and absence seizures: Video-EEG and EEG-fMRI evidence of overlapping but independent epileptogenic networks

EPILEPSIA, Issue 7 2009
Serge Chassagnon
Summary The distinction between typical absences and hypomotor seizures in patients having frontal lesions is difficult. In focal epilepsy, generalized-like interictal discharges can reflect either a coexistent generalized epileptic trait or a secondary bilateral synchrony. Using combined measures of the EEG and blood oxygenation level dependent (BOLD) activity, we studied a 50-year-old patient with both absence-like and symptomatic focal motor seizures. Focal activity induced activation in the lesional area and deactivation in the contralateral central cortex. Generalized spike-and-wave discharges (GSWDs) resulted also in perilesional activation, and multifocal symmetrical cortical and thalamic activations, and deactivation in associative cortical areas. Although the central cortex was involved during both types of epileptic activity, electroencephalography (EEG),functional magnetic resonance imaging (fMRI) revealed distinct neuronal networks at the time of the focal or generalized discharges, allowing a clear-cut differentiation of the generators. Whether the patient had distinct epileptic syndromes or distinct electrographic patterns from the lesional trigger remains debatable. [source]

Assessment and surgical outcomes for mild type I and severe type II cortical dysplasia: A critical review and the UCLA experience

EPILEPSIA, Issue 6 2009
Jason T. Lerner
Summary Recent findings on the clinical, electroencephalography (EEG), neuroimaging, and surgical outcomes are reviewed comparing patients with Palmini type I (mild) and type II (severe) cortical dysplasia. Resources include peer-reviewed studies on surgically treated patients and a subanalysis of the 2004 International League Against Epilepsy (ILAE) Survey of Pediatric Epilepsy Surgery. These sources were supplemented with data from University of California, Los Angeles (UCLA). Cortical dysplasia is the most frequent histopathologic substrate in children, and the second most common etiology in adult epilepsy surgery patients. Cortical dysplasia patients present with seizures at an earlier age than other surgically treated etiologies, and 33,50% have nonlocalized scalp EEG and normal magnetic resonance imaging (MRI) scans. 2-(18F)Fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) is positive in 75,90% of cases. After complete resection, 80% of patients are seizure free compared with 20% with incomplete resections. Compared with type I, patients with type II cortical dysplasia present at younger ages, have higher seizure frequencies, and are extratemporal. Type I dysplasia is found more often in adult patients in the temporal lobe and is often MRI negative. These findings identify characteristics of patients with mild and severe cortical dysplasia that define surgically treated epilepsy syndromes. The authors discuss future challenges to identifying and treating medically refractory epilepsy patients with cortical dysplasia. [source]

Outcome after hemispherectomy in hemiplegic adult patients with refractory epilepsy associated with early middle cerebral artery infarcts

EPILEPSIA, Issue 6 2009
Arthur Cukiert
Summary Purpose:, To study the outcome after hemispherectomy (HP) in a homogeneous adult patient population with refractory hemispheric epilepsy. Methods:, Fourteen adult patients submitted to HP were studied. Patients had to be at least 18 years old, and have refractory epilepsy, clearly focal lateralized seizures and unilateral porencephalus consistent with early middle cerebral artery infarct on magnetic resonance imaging (MRI). All patients were submitted to functional hemispherectomy. We analyzed age of seizure onset, age by the time of surgery, gender, seizure type and frequency, interictal and ictal electroencephalography (EEG) findings, MRI and IQ scores preoperatively; seizure frequency, drug regimen, and IQ outcome were studied postoperatively. Results:, Mean follow-up was 64 months. All patients had frequent daily seizures preoperatively. All patients had unilateral simple partial motor seizures (SPS); 11 patients had secondarily generalized tonic,clonic (GTC) seizures and five patients had complex partial seizures (CPS), preoperatively. All patients had hemiplegia and hemianopsia. Twelve patients had unilateral EEG findings, and in two epileptic discharges were seen exclusively over the apparently normal hemisphere. Twelve patients were seizure-free after surgery and two patients had at least 90% improvement in seizure frequency. Pre- and postoperative mean general IQ was 84 and 88, respectively. Five of the twelve Engel I patients were receiving no drugs at last follow-up. There was no mortality or major morbidity. Conclusions:, Our results suggest that well-selected adult patients might also get good results after HP. Although good results were obtained in our adult series, the same procedure yielded a much more striking result if performed earlier in life. [source]

Automated normalized FLAIR imaging in MRI-negative patients with refractory focal epilepsy

EPILEPSIA, Issue 6 2009
Niels K. Focke
Summary Background:, Patients with focal epilepsy that is refractory to medical treatment are often considered candidates for resective surgery. Magnetic resonance imaging (MRI) has a very important role in the presurgical work-up of these patients, but is unremarkable in about one-third of cases. These patients are often deferred from surgery or have a less positive outcome if surgery is eventually undertaken. The aim of this study was to evaluate our recently described voxel-based technique using routine T2-FLAIR (fluid-attenuated inversion-recovery) scans in MRI-negative patients and to compare the results with video-EEG (electroencephalography) telemetry (VT) findings. Methods:, We identified 70 epilepsy patients with refractory focal seizures who underwent VT and had a normal routine MRI. T2-FLAIR scans were bias-corrected, and intensity and spatially normalized (nFSI) using Statistical Parametric Mapping 5 (SPM5) as previously described. Individual scans were then compared against a set of 25 normal controls using a voxel-based method. Results:, SPM5 identified 10 patients with suprathreshold clusters (14.3%). In 50% of these there was concordance between the lobe of the most significant cluster and the presumed lobe of seizure onset, as defined by VT. All cases were concordant with respect to lateralization of the putative focus. Conclusion:, Using nFSI we identified focal structural cerebral abnormalities in 11.4% of patients with refractory focal seizures, and normal conventional MRI, that were fully or partially concordant with scalp VT. This voxel-based analysis of FLAIR scans, which are widely available, could provide a useful tool in the presurgical evaluation of epilepsy patients. Ongoing work is to compare these imaging findings with the results of intracranial EEG and histology of surgical resections. [source]

The spectrum of benign myoclonus of early infancy: Clinical and neurophysiologic features in 102 patients

EPILEPSIA, Issue 5 2009
Roberto H. Caraballo
Summary Purpose:, To redefine benign myoclonus of early infancy (BMEI) through analysis of clinical and neurophysiologic features in 102 patients with the aim to widen the spectrum of the syndrome, including a number of different clinical expressions of transient nonepileptic paroxysmal movements occurring in normal infants. Methods:, We recruited patients from one center in Argentina and two in Italy, including infants with normal neurologic and psychomotor development presenting with brief paroxysmal abnormal movements. Children with motor phenomena occurring only during sleep were excluded. Patients with abnormal interictal or ictal electroencephalography (EEG) findings were also excluded. The follow-up ranged from 2,40 years. Results:, One hundred and two infants (60 male) met the inclusion criteria. Age at onset ranged from 1,12 months, with a median age of 6.2 months. The following nonepileptic paroxysmal motor phenomena were recognized: (1) myoclonus, (2) spasms and brief tonic contractions, (3) shuddering, (4) atonia or negative myoclonus, (5) more than one type of motor phenomenon. In the majority of cases the episodes occurred only while awake and repeated several times a day. In 45 (44.1%) of the 102 cases contractions appeared in clusters. Conclusions:, Based on the analysis of clinical and EMG features in this large series of infants, we postulate that the spectrum of the syndrome is wider than initially suspected, and that the different transient motor manifestations and their correlation with different EMG patterns will allow recognition of this definitely benign condition comprising a variety of episodic motor phenomena in normal babies. [source]