Waking EEG Research Articles

Seizure-like episodes and EEG abnormalities in patients with long QT syndrome

PurposeThe congenital long QT-syndrome (cLQTS) is characterized by ventricular arrhythmias, syncope and sudden cardiac death. Many LQTS genes are also expressed in the brain and emerging evidence suggest that cardiac channelopathies can also cause epilepsy. The aim of the study is to explore evidence of epilepsy and/or EEG abnormalities in a cohort with a genotyped diagnosis of LQT1 or LQT2. MethodsAdult patients were randomly selected from the outpatient clinic and a random sample of healthy controls were recruited from the general population. Ictal semiology was explored in symptomatic patients. A 1 h 64-channel awake EEG was performed and analyzed by visual assessment. Brain connectivity was quantified by Directed Transfer Function (DTF) from the current source density estimate within the theta band (4–7 Hz). ResultsFifteen patients with LQT1, 20 with LQT2 and 20 controls were included. Seventy-one % of the patients reported loss of consciousness (LOC); 44% in combination with convulsions. EEG was abnormal in 34% of patients and 10% of controls (p < 0.05). Two patients had epileptiform or sharp activity. The fronto-parietal DTF connectivity was significantly altered in patients compared to controls (LQT1 p = 2.2 × 10−6, LQT2 p = 0.044). ConclusionSeizure-like episodes and EEG abnormalities were common in our cohort with cLQTS patients. However, we could not find firm evidence of epilepsy.Our findings reinforce the notion that cLQTS is a cardiocerebral channelopathy. Correct classification of seizures may be challenging to the clinician, but of vital importance for patients.

Optimal timing and differential significance of postoperative awake and sleep EEG to predict seizure outcome after temporal lobectomy

ObjectiveTo evaluate the prognostic value of postoperative EEGs to estimate post anterior temporal lobectomy (ATL) seizure outcome. MethodsWe studied postoperative EEGs in 325 consecutive patients who had minimum five years of post-ATL followup. Interictal epileptiform discharges (IEDs) present only during sleep were classified as sleep IEDs. We defined favorable final-year outcome as no seizures during the final one year and favorable absolute-postoperative outcome as no seizures during the entire postoperative period. ResultsAt mean follow-up of 7.3 ± 1.8 years, 281 (86.5%) patients had favorable final-year outcome while 161 (49.5%) had favorable absolute-postoperative outcome. IEDs on three months and one year EEG were associated with unfavorable outcomes while IEDs at 7th day had no association with outcomes. Sleep record increased the yield of IEDs by 30% at each time-point without compromising predictive value. EEG at one year predicted the risk of seizure recurrence on drug withdrawal. ConclusionWhile EEG at three months and at one-year after ATL predicted seizure outcome, EEG at 7th day was not helpful. Sleep record increases the sensitivity of postoperative EEG without compromising specificity. SignificanceBoth awake and sleep EEG provide useful information in postoperative period following ATL.

Yield of EEG monitoring in children with developmental disabilities is high

PurposeThe purpose of this study was to investigate the yield of a 2-hour electroencephalography (EEG) monitoring (awake and sleep) in children with developmental disabilities and without any clinically apparent seizures. MethodsIn this retrospective study, I investigated all children below 9 years of age who had developmental disabilities and were referred to Shiraz Comprehensive Epilepsy center for electroencephalographic investigation from June 2017 until January 2018. Exclusion criteria included any past history of neonatal seizures, febrile or afebrile seizures, and parental suspicion for seizures. We systematically obtained a brief clinical history and performed a 2-hour, awake and asleep EEG monitoring for all patients. ResultsThirty-two patients (23 males and 9 females) met all the inclusion and exclusion criteria; mean age (±standard deviation) was 4.1 (±2.1) years. Nineteen patients (59%) had an abnormal EEG: 15 patients (47%) had epileptiform discharges, and four children had abnormal background activity with no epileptiform discharges. ConclusionConsidering the high diagnostic yield of an awake and asleep EEG monitoring, as it was observed in the current study, this test on a screening basis can be reasonably justified in all children with developmental disabilities.

F167. Usefulness of combined surface polymyographic and back averaging techniques as essential tools in the evaluation of axial myoclonus of propriospinal origin: Two case presentation

Introduction Propriospinal Myoclonus (PSM) was first described as flexion or extension nonrhythmic repetitive myoclonic jerks arising in axial muscles, spreading to more caudal and rostral segments. Electrophysiologic features include a fixed pattern of muscle activation, slow conduction velocity, EMG burst duration of less than 1.000 ms, synchronous activation of agonist and antagonist muscles, and no facial involvement. The purpose of our study is to describe the usefulness of surface polymyography (sPMG) and jerk-lock techniques in the diagnosis of PSM. Methods Two patients with an involuntary periodic movement disorder were examined. Case 1: Patient underwent sPMG, back averaging and SSEPs testing. For jerk lock averaging, EMG with parallel EEG was registered from tibialis anterior (TA) muscle. SPMG activity was recorded with electrodes placed on paraspinalis dorsalis (PD) and lumbaris (PL), rectus femoris (RF), TA, and gastrocnemius (GM) muscles. The activity was scored for order of muscle recruitment, consistency of activation of the first muscle, consistency of pattern of spread of muscles involved, burst duration, and synchronous co-contraction muscle activation. Case 2: Back averaging, sPMG and SSEPs recordings were performed. For back averaging, sPMG was recorded from masseter, deltoideus, rectus abdominis (RA), PD, PL, RF and TA muscles. Triggers were set at burst onset of the initial muscle. SPMG recording muscles and study parameters were alike to the previous case, except that rectus abdominis rostral (RARA) and caudal aspect (RACA) muscles were added. Results Case 1: A 55-years old male presented with persistent jerks and involuntary lower limbs twitching. Awake and daytime sleep EEG did not show time-locked cortical correlate activity. SSEPs recordings were normal. During sPMG, burst activity started at PL muscle spreading upward to PD muscles and downward to right RF, TA and GM muscles. EMG burst occurred irregularly every 20–60 s, with duration of 100–800 ms. Case 2: A 60-years old male presented with excessive daytime sleepiness due to an acute onset of sudden abdominal jerks at the sleep- wake transition time. All jerks occurred at the transition from wake to sleep, and there were not Bereitschaftspotential preceding spontaneous activity. Burst started in RACA with rostro-caudal propagation. SPMG confirmed activation of the first muscle and consistency of pattern of spread. Jerks occurred irregularly every 20–60 s, with 100–800 ms duration. Co-contraction was evident. The latency of jerks recorded from RACA to RARA and from PD to TA was 55 ms and 95 ms, allowing calculation of spinal conduction velocity, found to be 9.1 ms−1 and 8.6 ms−1. SSEPs recordings were normal. Conclusion PMS is a rare movement disorder that arises from a spinal generator, with rostro-caudal propagation, which shows a typical electrophysiological pattern. We praise the using of sPMG to assess recruitment variability, combined with back averaging recordings to help to establish the diagnosis.

T144. EEG resting states are altered in focal epilepsy

Resting states represent the basic “atoms of thought” in the resting EEG but were found to be altered in a number of psychiatric and dementia conditions. In most studies, 4 basic maps are described (A = auditory, B = visual, C = salience, D = attention). In the present study we wanted to determine if EEG resting states are also altered in patients with chronic epilepsy 25 patients with chronic unifocal epilepsy were included. All patients underwent 37 channel EEGs. Three minutes of wake EEG without any detectable spikes were selected. We fitted the 4 EEG microstates to the: (i) EEG of patient without any visible spike and (ii) resting-state EEGs of 48 healthy-controls (HC). Global Explained Variance (GEV), Mean duration (MD) and Time Coverage (TC) were used to characterize the map amount. We found a significant GEV increase of map-D (p < 0.001), and decrease of map-C (p < 0.001). For map-C there was also a decrease of MD (p < 0.001) and TC (p < 0.01). These results did not change when fitting included the patient’s individual spike map. Physiologic resting state networks are significantly altered in patients with chronic epilepsy, which affects mainly the so-called salience (map-C) and attention states (map-D). Saliency networks include the anterior insula and dorsal anterior cingulate and play a crucial role in identifying relevant events to guide and adapt behavior. The increase of the attention map (parietal cortex, anterior cingulate, thalamus) probably reflects compensation of impaired salience functions. Further studies will determine if these changes could become an EEG biomarker of epilepsy, e.g. for patients with spike-negative EEG.

Abnormal coherence and sleep composition in children with Angelman syndrome: a retrospective EEG study

BackgroundAngelman syndrome (AS) is a neurodevelopmental disorder characterized by intellectual disability, speech and motor impairments, epilepsy, abnormal sleep, and phenotypic overlap with autism. Individuals with AS display characteristic EEG patterns including high-amplitude rhythmic delta waves. Here, we sought to quantitatively explore EEG architecture in AS beyond known spectral power phenotypes. We were motivated by studies of functional connectivity and sleep spindles in autism to study these EEG readouts in children with AS.MethodsWe analyzed retrospective wake and sleep EEGs from children with AS (age 4–11) and age-matched neurotypical controls. We assessed long-range and short-range functional connectivity by measuring coherence across multiple frequencies during wake and sleep. We quantified sleep spindles using automated and manual approaches.ResultsDuring wakefulness, children with AS showed enhanced long-range EEG coherence across a wide range of frequencies. During sleep, children with AS showed increased long-range EEG coherence specifically in the gamma band. EEGs from children with AS contained fewer sleep spindles, and these spindles were shorter in duration than their neurotypical counterparts.ConclusionsWe demonstrate two quantitative readouts of dysregulated sleep composition in children with AS—gamma coherence and spindles—and describe how functional connectivity patterns may be disrupted during wakefulness. Quantitative EEG phenotypes have potential as biomarkers and readouts of target engagement for future clinical trials and provide clues into how neural circuits are dysregulated in children with AS.

0245 Examining the Effects of Slow-wave Activity Disruption on Waking EEG Theta Activity

0245 Examining the Effects of Slow-wave Activity Disruption on Waking EEG Theta Activity

Improved cognitive morning performance in healthy older adults following blue-enriched light exposure on the previous evening

ObjectivesExposure to light can have acute alerting and circadian phase-shifting effects. This study investigated the effects of evening exposure to blue-enriched polychromatic white (BEL) vs. polychromatic white light (WL) on sleep inertia dissipation the following morning in older adults. MethodsTen healthy older adults (average age = 63.3 yrs; 6F) participated in a 13-day study comprising three baseline days, an initial circadian phase assessment, four days with 2-h evening light exposures, a post light exposure circadian phase assessment and three recovery days. Participants were randomized to either BEL or WL of the same irradiance for the four evening light exposures. On the next mornings at 2, 12, 22 and 32 min after each wake time, the participants completed a 90-s digit-symbol substitution test (DSST) to assess working memory, and objective alertness was assessed using a wake EEG recording. DSST and power density from the wake EEG recordings were compared between the two groups. ResultsDSST performance improved with time awake (p < 0.0001) and across study days in both light exposure groups (p < 0.0001). There was no main effect of group, although we observed a significant day x group interaction (p = 0.0004), whereby participants exposed to BEL performed significantly better on the first two mornings after light exposures than participants in WL (post-hoc, p < 0.05). On those days, the BEL group showed higher EEG activity in some of the frequency bins in the sigma and beta range (p < 0.05) on the wake EEG. ConclusionExposure to blue-enriched white light in the evening significantly improved DSST performance the following morning when compared to polychromatic white light. This was associated with a higher level of objective alertness on the wake EEG, but not with changes in sleep or circadian timing.

Serial changes in the paroxysmal discharges in rolandic epilepsy may predict seizure recurrence: A retrospective 3-year follow-up study

ObjectiveThe aim of this study was to assess the electrographic criteria related to seizure recurrence and determine age-related seizure recurrence in children with rolandic epilepsy under long-term follow-up. MethodsWe retrospectively analyzed the data belonging to 109 patients with rolandic epilepsy with sufficient information regarding disease course and follow-up duration longer than 3years. Patients were divided into two categories: Group A (n: 75), comprised of “patients having fewer than four seizures”, and Group B (n: 34), the “recurrence group comprised of patients having more than four seizures in the first three months”. The number of spikes per minute during both wakefulness and sleep, the localization of spikes other than centrotemporal region, and the duration of spike–wave activity were evaluated longitudinally, with repeated electroencephalogram (EEG) recordings every 6months. ResultsThe appearance of rolandic spikes in awake EEGs tended to be more prevalent in Group B than Group A. In Group B, spike rates significantly increased in the 12 and 18months after onset whereas spike rates increased significantly only 6months after onset in Group A. Seizure recurrence is mostly seen at 6–8years, and improvement becomes evident by age 12. The mean number of paroxysmal rolandic discharges during sleep was significantly higher in the younger age groups (3–5, 6–8), and the mean number of spikes per minute significantly decreased at ages 9–11 and over 12. ConclusionOur study demonstrates that extended periods of high frequency of paroxysmal discharges, initial frontal EEG focus, and persistence of awake interictal abnormalities are highly effective in predicting seizure recurrence in patients with rolandic epilepsy (RE).

Autistic Spectrum Disorder: What Video EEG Can Reveal about Its Pathophysiology

Objective: The autistic spectrum disorder (ASD) is a lifelong disorder characterized by a defect in communication, social interaction and stereotype patterns of behavior. The etiology of ASD is probably heterogenous. EEG abnormalities were observed in autistic patients, but these findings are mostly based on the visual analysis and scarce studies used quantified EEG parameters. Changes in connectivity of various parts of brain cortex were described in some studies and that is why we decided to investigate an EEG measure which is capable to evaluate the connectivity: The coherence. Study aims are to, Assess the hypothesis of connectivity changes; Assess the impact of epileptiform discharges on neuropsychological development. Methods: We present a small study of 24 children with ASD who underwent complex neuropsychological, neurological, sleep video-EEG (whole night and part-day) and MRI of brain investigations. The video EEG and MRI data are compared with quasi-normal EEG and MRI data from the control group. The EEG data were evaluated by experienced EEG reader and then the parts of EEG in relaxed wakefulness were quantified in terms of inter-channel coherence in several EEG channels. Results: A coherence analysis across several EEG channels revealed a statistically significant correlation between inter hemispheric coherence of the rear temporal regions (T5-T6) at 16-31 Hz and Childhood Autism Rating Scale raw scores. Conclusion: The changes in connectivity measured by the coherence might be a part of pathophysiology of the ASD.

The influence of EEG-detected nocturnal centrotemporal discharges on the expression of core symptoms of ADHD in children with benign childhood epilepsy with centrotemporal spikes (BCECTS): A prospective study in a tertiary referral center

Benign childhood epilepsy with centrotemporal spikes (BCECTS) is the most frequent benign focal epilepsy in childhood. Although it is described as a benign epilepsy syndrome, many studies have revealed that a significant number of patients have some degree of neuropsychological impairment.Thirty-two patients with BCECTS aged 6–11years were included in the study. All patients (without any antiepileptic or psychiatric medication) underwent all-night EEG monitoring and complex neuropsychological testing to diagnose the presence of core symptoms of attention-deficit/hyperactivity disorder (ADHD).The spike index (number of spikes per minute) on awake and asleep EEG, age at seizure onset, family history of epilepsy, and perinatal risks were correlated with the results of neuropsychological testing.Of the 32 patients, 21 patients (65.6%) fulfilled the criteria for ADHD diagnosis. Children who were younger at epilepsy onset demonstrated lower IQ and higher attention deficit (P=0.004) and higher impulsivity (P=0.016). The occurence of epileptiform discharges on nocturnal EEG was positively related to higher attention deficit and higher impulsivity.The findings are discussed in terms of how interictal discharges in the centrotemporal region during sleep affect the development of cognitive functions in children during critical epochs of neuropsychological development.

Characterisation of the Effects of Sleep Deprivation on the Electroencephalogram Using Permutation Lempel–Ziv Complexity, a Non-Linear Analysis Tool

Specific patterns of brain activity during sleep and waking are recorded in the electroencephalogram (EEG). Time-frequency analysis methods have been widely used to analyse the EEG and identified characteristic oscillations for each vigilance state (VS), i.e., wakefulness, rapid-eye movement (REM) and non-rapid-eye movement (NREM) sleep. However, other aspects such as change of patterns associated with brain dynamics may not be captured unless a non-linear-based analysis method is used. In this pilot study, Permutation Lempel–Ziv complexity (PLZC), a novel symbolic dynamics analysis method, was used to characterise the changes in the EEG in sleep and wakefulness during baseline and recovery from sleep deprivation (SD). The results obtained with PLZC were contrasted with a related non-linear method, Lempel–Ziv complexity (LZC). Both measure the emergence of new patterns. However, LZC is dependent on the absolute amplitude of the EEG, while PLZC is only dependent on the relative amplitude due to symbolisation procedure and thus, more resistant to noise. We showed that PLZC discriminates activated brain states associated with wakefulness and REM sleep, which both displayed higher complexity, compared to NREM sleep. Additionally, significantly lower PLZC values were measured in NREM sleep during the recovery period following SD compared to baseline, suggesting a reduced emergence of new activity patterns in the EEG. These findings were validated using PLZC on surrogate data. By contrast, LZC was merely reflecting changes in the spectral composition of the EEG. Overall, this study implies that PLZC is a robust non-linear complexity measure, which is not dependent on amplitude variations in the signal, and which may be useful to further assess EEG alterations induced by environmental or pharmacological manipulations.

Sleepless Night and Day, the Plight of Progressive Supranuclear Palsy.

To elucidate the unique sleep and waking characteristics in progressive supranuclear palsy (PSP), a neurodegenerative disease associated with motor deficits and dementia that largely affects the brainstem and thalamic regions. A total of 20 PSP and 16 healthy older adult controls participated in this study. The participants underwent an overnight polysomnography and multiple sleep latency test (MSLT) the following day. Prior to the MSLT last trial, they were asked to complete the Stanford Sleepiness Scale. Data were assessed for measures of latency to sleep onset, sleep duration, waking, and sleep staging during the night. Mean sleep latency, a measure of daytime sleepiness, sleep onset rapid eye movement (REM) periods, and microsleeps were studied with the MSLT. Spectral analysis of wake electroencephalogram (EEG) was performed for 30-second periods at the start of each MSLT trial. PSP took significantly longer time to fall asleep (p < .001), slept less during the night (p ≤ .001), and had more wake after sleep onset than controls (p ≤ .001). PSP had less N2 sleep (p < .05) and N3 sleep (p < .05), and REM sleep (p < .001) than controls. During the MSLT, PSP took significantly longer to fall asleep (p < .001), did not have microsleeps when they remained awake throughout the assessment periods, but were subjectively sleepier than controls (p < .05). Gamma power was increased during wake EEG in PSP (p < .01). Sleep/waking regulation and REM sleep regulation are disrupted in PSP, leading to profound sleep deprivation without recuperation. Our findings suggest a diminished homeostatic sleep drive in PSP. This hyperaroused state is unique and is a severely disabling feature of PSP.

Theta waves in children\u2019s waking electroencephalogram resemble local aspects of sleep during wakefulness

Vyazovskiy and colleagues found in rats’ multi-unit recordings brief periods of silence (off-states) in local populations of cortical neurons during wakefulness which closely resembled the characteristic off-states during sleep. These off-states became more global and frequent with increasing sleep pressure and were associated with the well-known increase of theta activity under sleep deprivation in the surface EEG. Moreover, the occurrence of such off-states was related to impaired performance. While these animal experiments were based on intracranial recordings, we aimed to explore whether the human surface EEG may also provide evidence for such a local sleep-like intrusion during wakefulness. Thus, we analysed high-density wake EEG recordings during an auditory attention task in the morning and evening in 12 children. We found that, theta waves became more widespread in the evening and the occurrence of widespread theta waves was associated with slower reaction times in the attention task. These results indicate that widespread theta events measured on the scalp might be markers of local sleep in humans. Moreover, such markers of local sleep, seem to be related to the well described performance decline under high sleep pressure.

P260 Spindle-shaped high frequency (±100 Hz) oscillatory activity in scalp EEG of children

Objectives To describe a spindle-shaped ripple observed in normal scalp EEG of children and to describe its correlation with age. Methods We included 22 patients from age 1 to 14 years. All children had a wake and sleep EEG without spikes. We marked ripples in sleep EEG, filtered between 80 and 250 Hz, in bipolar montage. We determined mean frequency, duration and root mean square amplitude. We counted the number of events per channel and calculated ripple rate over a period of 10 min. We categorised patients according to three groups: (1) no neurological diagnosis; (2) no epilepsy, but brain disorder; (3) diagnosis of epilepsy. In the ten children without a neurological diagnosis, we ran a lineal regression model with 10 log transformed cumulative ripple rate as dependent variable and age as predictor. Results We found this spindle-shaped ripple in 19 out of 22 children across diagnostic groups. Ripples occurred mostly on central channels (Cz-Pz). Mean frequency was 102 Hz, mean duration 70 ms, mean root mean square amplitude 0.95 μV. Ripple rate was negatively correlated with age ( F (1, 8) = 6.74; p = 0.03). Discussion The occurrence of these spindle-shaped ripples in normal EEGs and in healthy children indicates that this ripple activity is physiological. The negative correlation with age suggests its occurrence might be related to brain development. Conclusions Scalp EEGs without spikes can reveal physiological ripples in children. Significance This is the first study to describe physiological high frequency oscillations recorded in human neocortex with scalp EEG.

P358 EEG resting states are altered in focal epilepsy

Introduction Resting states represent the basic “atoms of thought” in the resting EEG but were found to be altered in a number of psychiatric and dementia conditions. In most studies, 4 basic maps are described (A = auditory, B = visual, C = salience, D = attention). In the present study we wanted to determine if EEG resting states are also altered in patients with chronic epilepsy Methods 25 patients with chronic unifocal epilepsy were included. All patients underwent 37 channel EEGs. Three minutes of wake EEG without any detectable spikes were selected. We fitted the 4 EEG microstates to the: (i) EEG of patient without any visible spike and (ii) resting-state EEGs of 48 healthy-controls (HC). Global Explained Variance (GEV), Mean duration (MD) and Time Coverage (TC) were used to characterize the map amount. Results We found a significant GEV increase of map-D (p Conclusion Physiologic resting state networks are significantly altered in patients with chronic epilepsy, which affects mainly the so-called salience (map-C) and attention states (map-D). Saliency networks include the anterior insula and dorsal anterior cingulate and play a crucial role in identifying relevant events to guide and adapt behavior. The increase of the attention map (parietal cortex, anterior cingulate, thalamus) probably reflects compensation of impaired salience functions. Further studies will determine if these changes could become an EEG biomarker of epilepsy, e.g. for patients with spike-negative EEG.

Differential spectrum approach to uncovering the electroencephalographic signatures of the opponent driving forces for sleep and wake underlying alternations of sleep and wake states

Abstract The opponent model of sleep-wake regulation postulated two opposing drives for sleep and wake. Simple measurement of slow wave activity does not allow their separation in the electroencephalographic (EEG) signal. However, we previously showed that scores on the 1st and 2nd principal components of variation in the EEG power spectrum can serve as markers of the opposing sleep and wake drives, respectively. The major purpose of the present report was to confirm and extend methodology for measurement of these drives by applying a new approach aimed on uncovering differences in their EEG signatures. A set of new single EEG measures was calculated in analysis of the waking and sleep EEG signals recorded in experimental studies of night sleep, multiple naps and sleep deprivation with, in total, 62 participants. Most measures summarized differences between a pair of the EEG spectra representing two distinct sleep-wake sub-states. Analysis of these differences between spectra revealed only two typical patterns that were interpreted as the spectral EEG signatures of the sleep and wake drives. The calculated single measures were subjected to principal component analysis. It yielded two largest principal components representing these opposing drives. Time courses of scores on these two principal components of variation in the calculated single measures closely resembled time courses of scores on two principal components of variation in the EEG power spectrum. It was concluded that such methodology can facilitate quantitative evaluations and model-based simulations of the opponent regulatory processes underlying normal and abnormal alternations of sleep and wake states.

Age-related "Sleep/nocturnal" tonic and tonic clonic seizure clusters are underdiagnosed in patients with Dravet Syndrome.

To describe the semiology and EEG characteristics of the age-related pattern of sleep/nocturnal (S/N) seizures in patients with Dravet Syndrome (DS). We retrospectively analysed the clinical and EEG data of DS patients followed at our reference centre for Rare Epilepsies. We included patients aged two years and older who fulfilled clinical and EEG criteria of DS (ILAE 1989). Genetic testing for SCN1A was done in all, followed by PCDH19 if this was negative. Patients showing a genetic abnormality in PCDH19 were excluded. Of 73 DS patients followed at our centre, 26 (15 males and 11 females), called the S/N group, experienced a switch in the circadian rhythm of seizures, from mainly awake/diurnal to mainly S/N seizures. We retrospectively analysed their clinical, EEG and genetic data. We have compared them to a second group of 7 patients (4 males and 3 females), aged more than 11years, the non-S/N group, who did not develop S/N seizures. We observed a pattern of S/N seizures concomitant with a decrease of awake seizures between 4 and 11years (median 6years 6months). S/N seizures were brief but often occurred in clusters of 2-15 per night. Seizures were mostly focal (26) with frontal-central onset (25) and tonic or tonic-vibratory in semiology. S/N seizure clusters were difficult to control despite many AEDs trials. Benzodiazepines reduced seizure recurrence within a cluster in some patients. While no significant differences were found between groups regarding clinical features, the presence of frontal and central anomalies on wake and sleep EEG was significantly associated with the presence of the S/N pattern. Patients with DS often develop a characteristic clinical and EEG pattern with S/N tonic and tonic clonic seizures that is often underdiagnosed. Seizure semiology and EEG pattern differ from LGS but may worsen the quality of sleep of such patients and their families. The possible role of this pattern in SUDEP occurring mainly during sleep and at the same age should be further explored. Current AEDs have limited efficacy and specific drug trials should be proposed.

Neuropsychological and behavioral disorders screening program in new-onset childhood epilepsies. Preliminary results using child behavior checklist evaluation

Objective: Cognitive impairments and emotional dysregulations are frequently encountered in children with all types of epilepsy. Retrospective studies highlight these difficulties but fail to determine their chronology of appearance which might be influenced by many factors (syndrome, seizure frequency, treatment…). Early detection of pre-existing or progressively developing deficits represent real challenges for global epilepsy-care programs. Methods: We developed a comprehensive approach for an early detection of behavioral and cognitive deficits in newly diagnosed epilepsies. During the first visit, children were received in a day hospital for a global evaluation including a sleep and awake EEG, somatic and neurological examination, an epilepsy nurse interview and a preliminary evaluation of behavior and social competences using the Child Behavior Checklist (CBCL, Achenbach, 1991). A first neuropsychological screening was conducted to assess attention abilities and executive functions using EpiTrack Junior (Helmstaedter, 2013). Depending on the results, a full neuropsychological evaluation can be scheduled. At the follow-up outpatient clinics, an epilepsy nurse interviewed the patient and his family using questionnaires on AEDs side effects and on “living with epilepsy”. A re-test with EpiTrack Junior is performed. Results: Preliminary results of the CBCL evaluation for idiopathic epilepsies (IE) – 36 children without epilepsy (NE); 37 children with IE (11 under AED treatment) – showed that at maximum 6 months from epilepsy onset, even benign forms of epilepsy score lower than NE in the Competences scale, assessing scholar, extrascholar and social skills (t(71)=2,01, p<.05), especially when under AEDs (t(45)=2,53, p<.02). Externalization scale showed that IE have more aggressive and delinquent behaviors as compared to NE (t(71)=2,16, p<.03) especially when under treatment (t(45)=2,55, p<.01). Conclusion: Our results underscore the need for an early multidisciplinary approach and detection of neuropsychological or behavioral deficits to engage appropriate reeducations.

The Usefulness of Nap Sleep Recording During Routine Electroencephalography: An Audit Study.

A measure to increase the electroencephalogram (EEG) outcome includes a short period of nap sleep during a routine standard EEG with the aim of increasing its sensitivity to interictal abnormalities or provoking seizures. As part of an ongoing auditing of our EEG data, we aimed to investigate the contribution of nap sleep during routine outpatient department based EEGs requested for a variety of reasons. EEG data at the Department of Clinical Physiology at Sultan Qaboos University Hospital, Oman, from July 2006 to December 2007 and from January 2009 to December 2010 (total 42 months) were reviewed. The EEGs were for patients older than 13-years referred for possible epilepsy, blackouts, headache, head trauma, and other non-specified attacks. The recording period was between 20 to 40 minutes. Abnormalities were identified during waking and nap sleep periods. A total of 2 547 EEGs were reviewed and 744 were abnormal (29.2%). Of those abnormal EEGs, nap sleep was obtained in 258 (34.7%) EEGs, and 39 (15.1%) showed abnormalities during nap sleep. Nineteen out of the 39 (48.7%) EEGs were abnormal during awake and nap sleep; and 20 (51.3%) were abnormal during nap sleep, which represented only 2.7% of the total abnormal EEGs (n = 744). The contribution of the short nap sleep to the pickup rate of interictal abnormalities in EEG was minimal. We recommend the EEG service to include one cycle of spontaneous sleep EEG directed at patients with a history suggestive of epilepsy if their awake EEGs are normal.