Dataset Information

Alterations of network synchrony after epileptic seizures: An analysis of post-ictal intracranial recordings in pediatric epilepsy patients.

ABSTRACT: OBJECTIVE:Post-ictal EEG alterations have been identified in studies of intracranial recordings, but the clinical significance of post-ictal EEG activity is undetermined. The purpose of this study was to examine the relationship between peri-ictal EEG activity, surgical outcome, and extent of seizure propagation in a sample of pediatric epilepsy patients. METHODS:Intracranial EEG recordings were obtained from 19 patients (mean age?=?11.4?years, range?=?3-20?years) with 57 seizures used for analysis (mean?=?3.0 seizures per patient). For each seizure, 3-min segments were extracted from adjacent pre-ictal and post-ictal epochs. To compare physiology of the epileptic network between epochs, we calculated the relative delta power (?) using discrete Fourier transformation and constructed functional networks based on broadband connectivity (conn). We investigated differences between the pre-ictal (?pre, connpre) and post-ictal (?post, connpost) segments in focal-network (i.e., confined to seizure onset zone) versus distributed-network (i.e., diffuse ictal propagation) seizures. RESULTS:Distributed-network (DN) seizures exhibited increased post-ictal delta power and global EEG connectivity compared to focal-network (FN) seizures. Following DN seizures, patients with seizure-free outcomes exhibited a 14.7% mean increase in delta power and an 8.3% mean increase in global connectivity compared to pre-ictal baseline, which was dramatically less than values observed among seizure-persistent patients (29.6% and 47.1%, respectively). SIGNIFICANCE:Post-ictal differences between DN and FN seizures correlate with post-operative seizure persistence. We hypothesize that post-ictal deactivation of subcortical nuclei recruited during seizure propagation may account for this result while lending insights into mechanisms of post-operative seizure recurrence.

SUBMITTER: Tomlinson SB

PROVIDER: S-EPMC7003130 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Alterations of network synchrony after epileptic seizures: An analysis of post-ictal intracranial recordings in pediatric epilepsy patients.

Tomlinson Samuel B SB Khambhati Ankit N AN Bermudez Camilo C Kamens Rebecca M RM Heuer Gregory G GG Porter Brenda E BE Marsh Eric D ED

Epilepsy research 20180405

<h4>Objective</h4>Post-ictal EEG alterations have been identified in studies of intracranial recordings, but the clinical significance of post-ictal EEG activity is undetermined. The purpose of this study was to examine the relationship between peri-ictal EEG activity, surgical outcome, and extent of seizure propagation in a sample of pediatric epilepsy patients.<h4>Methods</h4>Intracranial EEG recordings were obtained from 19 patients (mean age = 11.4 years, range = 3-20 years) with 57 seizures ...[more]

PMID: 29655171

Similar Datasets

Project description:Seizures are believed to be common presenting symptoms in neonates and children with spontaneous intracerebral hemorrhage (ICH). However, few data are available on the epidemiology of acute symptomatic seizures or the risk for later epilepsy.To define the incidence of and explore risk factors for seizures and epilepsy in children with spontaneous ICH. Our a priori hypotheses were that younger age at presentation, cortical involvement of ICH, acute symptomatic seizures after presentation, ICH due to vascular malformation, and elevated intracranial pressure requiring urgent intervention would predict remote symptomatic seizures and epilepsy.Prospective cohort study conducted between March 1, 2007, and January 1, 2012.Three tertiary care pediatric hospitals.Seventy-three pediatric subjects with spontaneous ICH including 20 perinatal (?37 weeks' gestation to 28 days) and 53 childhood subjects (>28 days to <18 years at presentation).Acute symptomatic seizures (clinically evident and electrographic-only seizures within 7 days), remote symptomatic seizures, and epilepsy.Acute symptomatic seizures occurred in 35 subjects (48%). Acute symptomatic seizures as a presenting symptom of ICH occurred in 12 perinatal (60%) and 19 childhood (36%) subjects (P = .07). Acute symptomatic seizures after presentation occurred in 7 children. Electrographic-only seizures were present in 9 of 32 subjects (28%) with continuous electroencephalogram monitoring. One-year and 2-year remote symptomatic seizure-free survival rates were 82% (95% CI, 68-90) and 67% (95% CI, 46-82), respectively. One-year and 2-year epilepsy-free survival rates were 96% (95% CI, 83-99) and 87% (95% CI, 65-95), respectively. Elevated intracranial pressure requiring acute intervention was a risk factor for seizures after presentation (P = .01; Fisher exact test), remote symptomatic seizures, and epilepsy (P = .03, and P = .04, respectively; log-rank test).Presenting seizures are common in perinatal and childhood ICH. Continuous electroencephalography may detect electrographic seizures in some subjects. Single remote symptomatic seizures occur in many, and development of epilepsy is estimated to occur in 13% of patients at 2 years. Elevated intracranial pressure requiring acute intervention is a risk factor for acute seizures after presentation, remote symptomatic seizures, and epilepsy.

Project description:Temporal lobe seizures have a significant chance to induce impairment of normal brain functions. Even after the termination of ictal discharges, during the post-ictal period, loss of consciousness, decreased responsiveness or other cognitive dysfunctions can persist. Previous studies have found various anatomical and functional abnormalities accompanying temporal lobe seizures, including an abnormal elevation of cortical slow waves. Intracranial electroencephalography studies have shown a prominent increase of lower frequency components during and following seizures that impair (complex partial seizures) but not those that preserve (simple partial seizures) normal consciousness and responsiveness. However, due to the limited spatial coverage of intracranial electroencephalography, the investigation of cortical slow waves cannot be easily extended to the whole brain. In this study, we used scalp electroencephalography to study the spectral features and spatial distribution of post-ictal slow waves with comprehensive spatial coverage. We studied simple partial, complex partial and secondarily generalized seizures in 28 patients with temporal lobe seizures. We used dense-array electroencephalography and source imaging to reconstruct the post-ictal slow-wave distribution. In the studied cohort, we found that a 'global' spectral power shift to lower frequencies accompanied the increased severity of seizures. The delta spectral power relative to higher frequency bands was highest for secondarily generalized seizures, followed by complex partial seizures and lastly simple partial seizures. In addition to this 'global' spectral shift, we found a 'regional' spatial shift in slow-wave activity. Secondarily generalized seizures and complex partial seizures exhibited increased slow waves distributed to frontal areas with spread to contralateral temporal and parietal regions than in simple partial seizures. These results revealed that a widespread cortical network including temporal and fronto-parietal cortex is involved in abnormal slow-wave activity following temporal lobe seizures. The differential spectral and spatial shifts of post-ictal electroencephalography activity in simple partial, complex partial and secondarily generalized seizures suggest a possible connection between cortical slow waves and behavioural and cognitive changes in a human epilepsy model.

Dataset Information

Alterations of network synchrony after epileptic seizures: An analysis of post-ictal intracranial recordings in pediatric epilepsy patients.

Publications

Alterations of network synchrony after epileptic seizures: An analysis of post-ictal intracranial recordings in pediatric epilepsy patients.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure