Epileptiform discharges augmented during sleep: is it a trait with diverse clinical presentation according to age of expression? Epilepsy Res. 2010;89:113-120. [PMID: 19910161 DOI: 10.1016/j.eplepsyres.2009.10.004]

Neurobehavioral deterioration associated with sleep-augmented epileptiform abnormalities: A steroid responsive state in children

OBJECTIVE

Retrospective case record analysis of children with Neurobehavioral Deterioration associated with Sleep-augmented Epileptiform abnormalities (NDSE).

METHODS

Hospital records of children with NDSE (July, 2015 through December, 2016) were analyzed. Children were categorized as: Encephalopathy with electrical status epilepticus in sleep (ESES) if sleep EEG Spike-wave-Index (SWI) was ≥50% and sleep-induced epileptiform activity (SIEA)-related cognitive dysfunction if SWI ≥25% but <50%. Demography, neurobehavior profile (IQ/SQ and behavior using validated psychometric tools), etiology, investigations and treatment details were documented. Outcome assessment was based on three-month follow-up records.

RESULTS

Eighteen children with NDSE {12 boys; median age at diagnosis: 7.5 years (IQR: 6-10 years); SIEA (7); ESES (11)} were included. Etiology was structural (23%) and presumed genetic (77%). All children received intravenous-methylprednisolone pulse followed by oral steroids for eight weeks. Electroencephalography of children with SIEA was partly organized with median SWI of 40% (IQR 35, 42), with anterior-predominant epileptiform abnormalities and less apparent secondary synchronization. Children with ESES had a disorganized EEG background with median SWI of 80% (IQR 66, 95). Both SIEA and ESES groups had a similar neurobehavior profile. Behavior scores improved in 6/8 children with ESES and 5/7 in SIEA post steroids. In both the groups, median SWI improved (to <5% in SIEA, 45% in ESES). Mild improvement in IQ/SQ was also noted {SIEA [Median (IQR): 3 (1.6, 4.3)]; ESES [Median (IQR): 3.8 (2.8, 7)]}.

CONCLUSION

The study supports the fact that SWI >50% in the nap EEG is not mandatory for the diagnosis of ESES, thus it should not be a constraint for steroid treatment.

High-Frequency Oscillations on Interictal Epileptiform Discharges in Routinely Acquired Scalp EEG: Can It Be Used as a Prognostic Marker?

Introduction

Despite all the efforts for optimizing epilepsy management in children over the past decades, there is no clear consensus regarding whether to treat or not to treat epileptiform discharges (EDs) after a first unprovoked seizure or the optimal duration of therapy with anti-seizure medication (ASM). It is therefore highly needed to find markers on scalp electroencephalogram (EEG) that can help identify pathological EEG discharges that require treatment.

Aim of the study

This retrospective study aimed to identify whether the coexistence of ripples/high-frequency oscillations (HFOs) with interictal EDs (IEDs) in routinely acquired scalp EEG is associated with a higher risk of seizure recurrence and could be used as a prognostic marker.

Methods

100 children presenting with new onset seizure to Children’s Medical Center- Dallas during 2015–2016, who were not on ASM and had focal EDs on an awake and sleep EEG recorded with sample frequency of 500 HZ, were randomly identified by database review. EEGs were analyzed blinded to the data of the patients. HFOs were visually identified using review parameters including expanded time base and adjusted filter settings.

Results

The average age of patients was 6.3 years (±4.35 SD). HFOs were visually identified in 19% of the studied patients with an inter-rater reliability of 99% for HFO negative discharges and 78% agreement for identification of HFOs. HFOs were identified more often in the younger age group; however, they were identified in 11% of patients >5 years old. They were more frequently associated with spikes than with sharp waves and more often with higher amplitude EDs. Patients with HFOs were more likely to have a recurrence of seizures in the year after the first seizure (P < 0.05) and to continue to have seizures after 2 years (P < 0.0001). There was no statistically significant difference between the two groups with regards to continuing ASM after 2 years.

Conclusion

Including analysis for HFOs in routine EEG interpretation may increase the yield of the study and help guide the decision to either start or discontinue ASM. In the future, this may also help to identify pathological discharges with deleterious effects on the growing brain and set a new target for the management of epilepsy.

The Value of Electroencephalogram in Assessing Children With Speech and Language Impairments

Purpose We sought to estimate the prevalence of isolated epileptiform activity (IEA) in children with speech and language impairments and discuss the utility of an electroencephalogram (EEG) in assessing these children. Method We conducted a systematic review and searched for eligible studies in 8 databases. All languages were included, and meta-analyses were performed. Results We found 55 prevalence estimates (8 with control group). The odds of having IEA were 6 times greater for children with speech and language impairments than for typically developing children. The overall pooled prevalence of IEA was 27.3%. A wide variation between the prevalence estimates was, to a certain degree, explained by type of impairment (8.1% in speech impairments, 25.8% in language impairments, and 51.5% in language regression). Sleep EEGs detected a significantly higher prevalence than awake EEGs. Although the presence of epilepsy gave a significantly higher prevalence than if epilepsy was not present, 33.5% of children with language impairment but without epilepsy were found to have IEA in sleep EEGs. Conclusions This systematic review shows that IEA is 6 times more prevalent in children with speech and language impairment than in typically developing children. However, the prevalence rates vary to a great extent. Uncovering IEA will, in addition to information from other clinical assessments, provide a more comprehensive understanding of the child's impairments. We argue that, although EEG is of questionable value when assessing children with speech impairments, sleep EEG could be valuable when assessing children with language impairments and, in particular, children who experience language regression.

Watch the language! Language and linguistic-cognitive abilities in children with nocturnal epileptiform activity

We studied the language and linguistic-cognitive abilities of a group of children with nocturnal epileptiform activity (NEA; N=33) who were hospitalized at a tertiary epilepsy hospital. The children were compared with two groups: one age- and gender-matched group (N=33) and one group matched on language ability (vocabulary) and gender (N=66). We also examined how NEA-related variables affected language abilities. Overall, the children with NEA showed delayed language abilities and a trend for specific difficulties with phonology and naming speed. We did not find firm evidence that the amount of NEA, the use of antiepileptic drugs (AEDs), and the lateralization and localization of NEA had an effect on language. However, we found that children with right-lateralized epileptiform activity seemed to have specific difficulties with naming speed. Additionally, our results indicated that NEA located in the centrotemporal areas particularly affected phonology and orthographic skills.

Childhood epilepsy and sleep

Sleep and epilepsy are two well recognized conditions that interact with each other in a complex bi-directional way. Some types of epilepsies have increased activity during sleep disturbing it; while sleep deprivation aggravates epilepsy due to decreased seizure threshold. Epilepsy can deteriorate the sleep-related disorders and at the same time; the parasomnias can worsen the epilepsy. The secretion of sleep-related hormones can also be affected by the occurrence of seizures and supplementation of epileptic patients with some of these sleep-related hormones may have a beneficial role in controlling epilepsy.

Subclinical epileptiform activity in children with electrical status epilepticus during sleep: effects on cognition and behavior before and after treatment with levetiracetam

We performed a double-blind placebo-controlled crossover study of the effects of spike activity during sleep and when awake on learning, long-term memory, vigilance and behavior before and after treatment with levetiracetam in children with electrical status epilepticus during sleep. At baseline, verbal learning declined with increasing spike activity, but there were no relations between spike activity and memory, vigilance or behavior. Levetiracetam was effective in reducing sleep-related spike activity, but on a group level, this had no clear effects on behavior, vigilance or learning and memory. Our results do not allow firm conclusions whether to treat nocturnal epileptiform activity or not; larger samples and longer follow-up may be needed.

Coexistence of epileptic encephalopathy with continuous spike-and-wave during sleep, atypical benign partial epilepsy, and fixation-off sensitivity in two siblings

Epileptic encephalopathy with continuous spike-and-wave during sleep is a rare age-related childhood encephalopathy characterized by neuropsychological and motor impairment, epilepsy, and typical EEG findings. Fixation-off sensitivity denotes forms of epilepsy and/or EEG abnormalities that occur during eye closure. The authors describe a girl with developmental regression, electrical status epilepticus during sleep (documented by video/EEG recording), and intermittent myoclonus. Her younger brother was diagnosed with atypical benign partial epilepsy, and his repeated video/EEG recordings unexpectedly showed fixation-off sensitivity.

Sleep physiology and sleep disorders in childhood

Sleep has long been considered as a passive phenomenon, but it is now clear that it is a period of intense brain activity involving higher cortical functions. Overall, sleep affects every aspect of a child's development, particularly higher cognitive functions. Sleep concerns are ranked as the fifth leading concern of parents. Close to one third of all children suffer from sleep disorders, the prevalence of which is increased in certain pediatric populations, such as children with special needs, children with psychiatric or medical diagnoses and children with autism or pervasive developmental disorders. The paper reviews sleep physiology and the impact, classification, and management of sleep disorders in the pediatric age group.