Idiopathic Generalized Epilepsy Research Articles

Analytic information processing style in epilepsy patients.

Relevant to the study of epileptogenesis is learning processing, given the pivotal role that neuroplasticity assumes in both mechanisms. Recently, evoked potential analyses showed a link between analytic cognitive style and altered neural excitability in both migraine and healthy subjects, regardless of cognitive impairment or psychological disorders. In this study we evaluated analytic/global and visual/auditory perceptual dimensions of cognitive style in patients with epilepsy. Twenty-five cryptogenic temporal lobe epilepsy (TLE) patients matched with 25 idiopathic generalized epilepsy (IGE) sufferers and 25 healthy volunteers were recruited and participated in three cognitive style tests: "Sternberg-Wagner Self-Assessment Inventory", the C. Cornoldi test series called AMOS, and the Mariani Learning style Questionnaire. Our results demonstrate a significant association between analytic cognitive style and both IGE and TLE and respectively a predominant auditory and visual analytic style (ANOVA: p values <0,0001). These findings should encourage further research to investigate information processing style and its neurophysiological correlates in epilepsy.

Prevalence and risk factors of seizure clusters in adult patients with epilepsy

PurposeIn the current study, we explored the prevalence of physician-confirmed seizure clusters. We also investigated potential clinical factors associated with the occurrence of seizure clusters overall and by epilepsy type. MethodsWe reviewed medical records of 4116 adult (≥16years old) outpatients with epilepsy at our centers for documentation of seizure clusters. Variables including patient demographics, epilepsy details, medical and psychiatric history, AED history, and epilepsy risk factors were then tested against history of seizure clusters. Patients were then divided into focal epilepsy, idiopathic generalized epilepsy (IGE), or symptomatic generalized epilepsy (SGE), and the same analysis was run. ResultsOverall, seizure clusters were independently associated with earlier age of seizure onset, symptomatic generalized epilepsy (SGE), central nervous system (CNS) infection, cortical dysplasia, status epilepticus, absence of 1-year seizure freedom, and having failed 2 or more AEDs (P<0.0026). Patients with SGE (27.1%) were more likely to develop seizure clusters than patients with focal epilepsy (16.3%) and IGE (7.4%; all P<0.001). Analysis by epilepsy type showed that absence of 1-year seizure freedom since starting treatment at one of our centers was associated with seizure clustering in patients across all 3 epilepsy types. In patients with SGE, clusters were associated with perinatal/congenital brain injury. In patients with focal epilepsy, clusters were associated with younger age of seizure onset, complex partial seizures, cortical dysplasia, status epilepticus, CNS infection, and having failed 2 or more AEDs. In patients with IGE, clusters were associated with presence of an aura. Only 43.5% of patients with seizure clusters were prescribed rescue medications. ConclusionPatients with intractable epilepsy are at a higher risk of developing seizure clusters. Factors such as having SGE, CNS infection, cortical dysplasia, status epilepticus or an early seizure onset, can also independently increase one’s chance of having seizure clusters.

Long-term safety and efficacy outcomes of adjunctive perampanel: an open-label extension (OLEx) of a Phase III study in patients with drug-resistant primary generalized tonic-clonic (PGTC) seizures in idiopathic generalized epilepsy (IGE) (P5.233)

Long-term safety and efficacy outcomes of adjunctive perampanel: an open-label extension (OLEx) of a Phase III study in patients with drug-resistant primary generalized tonic-clonic (PGTC) seizures in idiopathic generalized epilepsy (IGE) (P5.233)

Amygdala enlargement: Temporal lobe epilepsy subtype or nonspecific finding?

ObjectiveAmygdala enlargement (AE) is observed in patients with temporal lobe epilepsy (TLE), which has led to the suggestion that it represents a distinct TLE subtype; however, it is unclear whether AE is found at similar rates in other epilepsy syndromes or in healthy controls, which would limit its value as a marker for focal epileptogenicity. MethodsWe compared rates of AE, defined quantitatively from high-resolution T1-weighted MRI, in a large multi-site sample of 136 patients with nonlesional localization related epilepsy (LRE), including TLE and extratemporal (exTLE) focal epilepsy, 34 patients with idiopathic generalized epilepsy (IGE), and 233 healthy controls (HCs). ResultsAE was found in all groups including HCs; however, the rate of AE was higher in LRE (18.4%) than in IGE (5.9%) and HCs (6.4%). Patients with unilateral LRE were further evaluated to compare rates of concordant ipsilateral AE in TLE and exTLE, with the hypothesis that rates of ipsilateral AE would be higher in TLE. Although ipsilateral AE was higher in TLE (19.4%) than exTLE (10.5%), this difference was not significant. Furthermore, among the 25 patients with unilateral LRE and AE, 13 (52%) had either bilateral AE or AE contralateral to seizure onset. ConclusionResults suggest that AE, as defined with MRI volumetry, may represent an associated feature of nonlesional localization related epilepsy with limited seizure onset localization value.

EFHC1 mutation in Indian juvenile myoclonic epilepsy patient.

SummaryObjectiveJuvenile myoclonic epilepsy (JME) is the most common form of idiopathic generalized epilepsies (IGEs) and is genetically heterogeneous. Mutations in EFHC1 cause JME. Because about 2 million people in India are affected by JME alone, we investigated the prevalence of mutations in the EFHC1 gene in the Indian population with JME. We studied 63 patients with JME and 80 healthy controls.MethodsClinical identification of JME was evaluated using established criteria. Following clinical evaluation of the patients and confirming presence of JME, blood samples were collected from each patient and healthy individual. Subsequently, genomic DNA was extracted from the blood samples. Eleven exons of the EFHC1 gene were individually amplified by polymerase chain reaction (PCR) for each DNA sample. The PCR products were then purified and sequenced commercially. The identified DNA variants were sequenced at least twice in both the forward and reverse directions and compared with the Exome Aggregation Consortium (ExAC) database.ResultsWe found five heterozygous and one homozygous variant. We found three novel coding variants 661C→T, 779 G →A, and 730 C→T, which lead to R221C, R260Q, and R244STOP amino acid substitutions, respectively. The coding variant 475 C→T, resulting in the amino acid substitution R159W, reported earlier as polymorphism, was also identified in both patient and control populations.SignificanceDetection of these three novel variants, excluding R159W, which is considered polymorphism, expands the range of possible mutations in the EFHC1 gene. The novel variants that we are reporting herein have not been mentioned before as occurring in JME patients of other ethnic population. Therefore, these novel coding variants may be confined to the Indian JME population. Further studies on the mutational spectrum of EFHC1 in a larger number of Indian JME patients concurrent with their mode of inheritance and underlying functional assays should establish whether EFHC1 could be a panethnic gene for JME.

Attention deficits in children with epilepsy: Preliminary findings.

Attention difficulties are a common clinical complaint among children with epilepsy. We aimed to compare a range of attentional abilities between groups of children with two common epilepsy syndromes, Temporal Lobe Epilepsy (TLE) and Idiopathic Generalized Epilepsy (IGE), and to healthy controls. We also investigated whether epilepsy factors (laterality of seizure focus, epilepsy onset, duration, and severity) were related to attentional abilities. Multiple dimensions of attention (selective, sustained, and divided attention and attentional control) were assessed directly with standardized neuropsychological measures in 101 children aged 6-16years (23 children with TLE, 20 with IGE and 58 healthy controls). Attention was also assessed indirectly, via a parent-report measure. Children with TLE performed worse than children with IGE (p=0.013) and healthy controls (p<0.001) on a test of attentional control, but no between-group differences were apparent on tests of other attentional abilities. Compared to healthy controls, greater attention problems were reported by parents of children with TLE (p=0.006) and IGE (p=0.012). Left-hemisphere seizure focus and greater epilepsy severity were associated with poorer attentional control and sustained-divided attention, respectively, but no other epilepsy factors were associated with attentional abilities. These findings suggest that children with localization-related epilepsy, but not generalized epilepsy, may be at risk of deficits in attentional control. Interventions aimed at improving attentional control may be targeted at children with localization-related epilepsy, particularly those with a left-hemisphere seizure focus, who appear to be particularly susceptible to this type of attentional deficit.

Patterns of Gray Matter Abnormalities in Idiopathic Generalized Epilepsy: A Meta-Analysis of Voxel-Based Morphology Studies.

ObjectiveWe aimed to identify the consistent regions of gray matter volume (GMV) abnormalities in idiopathic generalized epilepsy (IGE), and to study the difference of GMV abnormalities among IGE subsyndromes by applying activation likelihood estimation (ALE) meta-analysis.MethodsA systematic review of VBM studies on GMV of patients with absence epilepsy (AE), juvenile myoclonic epilepsy (JME), IGE and controls indexed in PubMed and ScienceDirect from January 1999 to June 2016 was conducted. A total of 12 IGE studies, including 7 JME and 3 AE studies, were selected. Meta-analysis was performed on these studies by using the pooled and within-subtypes analysis (www.brainmap.org). Based on the above results, between-subtypes contrast analysis was carried out to detect the abnormal GMV regions common in and unique to each subtype as well.ResultsIGE demonstrated significant GMV increase in right ventral lateral nucleus (VL) and right medial frontal gyrus, and significant GMV decrease in bilateral pulvinar. For JME, significant GMV increase was seen in right medial frontal gyrus, right anterior cingulate cortex (ACC), while significant GMV decrease was found in right pulvinar. In AE, the most significant GMV increase was found in right VL, and slight GMV reduction was seen in right medial dorsal nucleus, right subcallosal gyrus, left caudate and left precuneus. No overlapped and unique regions with significant GMV abnormalities were found between JME and AE.SignificanceThis meta-analysis demonstrated that thalamo-frontal network was a structure with significant GMV abnormality in IGE, and the IGE subsyndromes showed different GMV abnormal regions. These observations may provide instructions on the clinical diagnosis of IGE.

Impaired Executive Function by Interictal Epileptiform Discharges in Patients with Idiopathic Generalized Epilepsy

Objective: Many patients with Idiopathic Generalized Epilepsy (IGE) exhibit cognitive deficits. Interictal Epileptiform Discharges (IEDs) may contribute to cognitive impairment in epilepsy; however, the relationship between IEDs and cognitive impairment is unclear. Methods: In this study, we analysed executive function in three groups: IGE patients with IEDs, IGE patients without IEDs and healthy controls. Executive function was assessed using the Stroop Test, the Verbal Fluency Test, the Digit Span Test and Wisconsin Card-Sorting Test. Results: The IGE patients with IEDs performed worse on executive function tests compared with patients without IEDs. Furthermore, the IGE patients without IEDs performed worse compared with healthy controls. There were significant differences between the three groups in performance on the Stroop Test, the Digit Span Test (forward and backward), Verbal Fluency Test (animals, fruits) and the subscales of WCST (Categories Completed, Correct Response, Total Errors and Preservative Errors). Conclusion: These results suggest that executive function in patients with IGE is impaired and is further impaired by IEDs. Future studies should determine whether well-controlled patients with IGE could benefit from antiepileptic treatment.

Pathomorphosis of idiopathic generalized epilepsy. Juvenile forms

To investigate the pathomorphosis of idiopathic generalized epilepsy (IGE) in the aspect of prognosis. The study involved 1480 patients with epilepsy including 281 patients with IGE. 'Juvenile' forms were diagnosed in 228 patients. Relapse of seizures in anamnesis occurred in 19% out of 105 patients with juvenile myoclonic epilepsy (JME). Remission was achieved in 59.2% out of 76 patients with long-term follow-up. Out of 35 patients with juvenile absence epilepsy (JAE), relapse of seizures in anamnesis occurred in 25.7%. Out of 24 patients with long-term follow-up, remission was achieved in 70.8%. Out of 88 patients with IGE with generalized tonic clonic-seizures, relapse of seizures in anamnesis occurred in 15%. Out of 60 patients with long-term follow-up, remission was achieved in 86.7%. The main features of epilepsy pathomorphosis in all groups of patients were the decrease of informativeness of routine EEG, reduction in the frequency and duration of seizures, occurrence of seizures in the discontinuation of therapy and/or under the influence of provoking factors.

Diagnostic Value of magnetic resonance spectroscopy in Morphometrical Analysis of basal ganglia in patients with Idiopathic Generalized Epilepsy

ntroduction: Idiopathic generalized epilepsy (IGE) is a kind of epilepsy that has tonic-colonic characteristic and myocolonic tensions and its clinical symptom starts from the first 20 years of the life. Proton magnetic resonance spectroscopy (H1-MRS) technique applies as a noninvasive procedure to find metabolic disorders by evaluating brain metabolites. Purpose of this study was metabolical and morphological analysis of the thalamus using MRS imaging in patients with IGE. Materials and Methods: Applying H1-MRS (technique: PRESS-CSI), we evaluated thalamus images of 63 people (35 controls: 23 males, 12 females, ranging in age 19-46 years, average: 34.8±0.62 years) and 28 IGE patients (10 males, 18 females, ranging in age 20-49 years, average: 37.4±1.04 years). The data analyzed by SPSS (v.20). Results: Comparing the average NAA/Cr for the right thalamus, a significant reduction was seen between the control group and the IGE patients (p<0.0001). Likewise, for the left thalamus, the NAA/Cr was significantly decreased when we compared it for the control group and the IGE patients (p<0.001). Conclusion: H1-MRS could be a suitable diagnostic technique to evaluate epilepsy in IGE patients. The possible alteration of neuronal pathways in the thalamo-cortical circuit seems to play a critical role in epileptogenesis of IGE.

Sleep onset uncovers thalamic abnormalities in patients with idiopathic generalised epilepsy.

The thalamus is crucial for sleep regulation and the pathophysiology of idiopathic generalised epilepsy (IGE), and may serve as the underlying basis for the links between the two. We investigated this using EEG-fMRI and a specific emphasis on the role and functional connectivity (FC) of the thalamus. We defined three types of thalamic FC: thalamocortical, inter-hemispheric thalamic, and intra-hemispheric thalamic. Patients and controls differed in all three measures, and during wakefulness and sleep, indicating disorder-dependent and state-dependent modification of thalamic FC. Inter-hemispheric thalamic FC differed between patients and controls in somatosensory regions during wakefulness, and occipital regions during sleep. Intra-hemispheric thalamic FC was significantly higher in patients than controls following sleep onset, and disorder-dependent alterations to FC were seen in several thalamic regions always involving somatomotor and occipital regions. As interactions between thalamic sub-regions are indirect and mediated by the inhibitory thalamic reticular nucleus (TRN), the results suggest abnormal TRN function in patients with IGE, with a regional distribution which could suggest a link with the thalamocortical networks involved in the generation of alpha rhythms. Intra-thalamic FC could be a more widely applicable marker beyond patients with IGE.

The efficacy and safety of valproic acid medications with controlled active ingredient release in adults in real clinical practice from the position of pharmacokinetic and pharmacogenetic approaches

Objective: to analyze the efficacy and tolerability of sustained-release sodium valproate (SV) in adult patients with focal or generalized epilepsy in real clinical practice in three regions (Krasnoyarsk, Moscow, and Samara) of the Russian Federation. Patients and methods. The investigation enrolled adult patients with focal (n=63) or generalized (n=31) epilepsy who had received a stable dose of the drug alone (n=64 (68%)) or in combination with one of the antiepileptic drugs (AEDs): levetiracetam, lamotrigine, topiramate, or perampanel (n=30 (31.9%)) for at least one year. According to the brand name of drugs, their use frequency was as follows: Depakine® Chrono (61.7%), Convulex® (16%), Depakine® Chronosphere (9.6%), Valparine® XP (8.5%), and Encorate® Chrono (4.3%). Results. For a period of over one year, most patients with focal epilepsy (FE) (49.2%) and idiopathic generalized epilepsy (IGE) (67.7%) achieved a remission of seizures when they used moderate (1000 mg) and low (<1000 mg) daily doses of SV. Among the PE and IGE patients taking Depakine Chronosphere, the remission rate was highest, amounting to 100 and 75%, respectively. The efficacy of SV in both FE and IGE decreased in the following order: Depakine Chrono, Convulex, and Valparine XP. Clinical remission was achieved in none of the patients taking Encorate Chrono. The most common unwanted side reactions (USRs) were weight gain, menstrual disorders, tremor, and hair loss; however, their total frequency (16%) proved to be substantially lower than previously considered. The side effects were observed in one-half of the patients receiving a daily SV dose of 1000 mg and more, USRs were noted during combination therapy with SV medications and topiramate (n=5) or lamotrigine (n=2). USRs were frequently observed in the heterozygous carriers of the single nucleotide polymorphisms (SNPs) CYP2C9*3 (27.3%) versus those who had the common (wild-type) allele variant CYP2C9*1, but USRs were recorded mainly in the heterozygous carriers of CYP2C9*3 and CYP2C9*2 who received low daily doses of SV. The frequency of the CYP2C9 gene among SNPs proved to be highest: CYP2C9*1/*1 in 68 (72.3%) patients, CYP2C9*2 in 14 (14.9%), and CYP2C9*3 in 11 (11.7%). The compound heterozygous CYP2C9*2/*3 genotype was recorded in one (1.06%) case. The inadequate effect of AEDs requires therapeutic drug monitoring (TDM); and to rule out USRs calls for pharmacogenetic studies before or at the early stages of titration of SV, by determining its starting dosage, titration rate, and therapeutic dose. TDM and a pharmacogenetics study allow optimization of the personalized choice of AEDs.

Perampanel in the treatment of patients with epilepsy

Development of new antiepileptic drugs (AED) does not stop due to the fact that the number of patients with pharmacoresistant epilepsy remains at about 30%. One of the newest AEDs is perampanel (PER), a selective, non-competitive AMPA receptor antagonist to target post-synaptic glutamate transmission. PER is approved in the Russian Federation as adjunctive treatment for focal seizures with or without secondarily generalized seizures and for primary generalized tonic-clonic (PGTC) seizures in idiopathic generalized epilepsy (IGE) in patients with epilepsy aged ≥12 years. The drug is effective and well-tolerated in the dose of 4-8 mg/day, and most side effects are dose-dependent. The high efficacy of PER combined with the good tolerability, absence of life-threatening adverse reactions and convenient intake allow us to recommend PER as the first choice additional drug in treatment of patients with epilepsy.

JUVENILE MYOCLONIC EPILEPSY: FOCUS ON THE USE OF TOPIRAMATE (LITERATURE REVIEW AND OWN DATA)

Juvenile myoclonic epilepsy (JME) is an inherited genetic syndrome within the group of idiopathic generalized epilepsies (IGE). The disease is characterized by an adolescence-onset with massive myoclonic seizures often combined with generalized convulsive seizures and absence seizures and by typical changes in the electroencephalogram appearing as short generalized polyspike-and-wave epileptiform discharges with a frequency of 3–6 Hz. Despite the high rate of remission (75–85 %) in patients receiving adequate therapy, this form of epilepsy brings more significant inconveniences for patients than many other forms of IGE. Such factors as violation of sleep hygiene, missing the doses of antiepileptic drugs (AED) or discontinuing the therapy cause recurrence of seizures in the vast majority of patients with JME, even in those with long-term remission. Due to the high recurrence rate in patients with JME, the treatment is usually lengthy; thus, the issues of its efficacy and tolerability, as well as the choice of starting therapy are particularly important in the case of JME. The impact of AED on the reproductive functions in women is a subject of major concern, since the active period of the disease and antiepileptic therapy covers the adult (and often adolescent) age. Valproic acid was widely used for treatment of JME, but now this drug is prescribed less frequently (especially in girls and women) due to the possible negative impact on reproductive function and its teratogenic effect. So, choosing an alternative drug with high efficacy and tolerability is crucial for patients with JME. The authors present their own experience of JME treatment with topiramate. Our results suggest that topiramate is a highly effective well-tolerated drug that can be used for JME therapy without a significant impact on the reproductive functions in female patients.

Thalamic hypoperfusion and disrupted cerebral blood flow networks in idiopathic generalized epilepsy: Arterial spin labeling and graph theoretical analysis

PurposeThe aim of this study was to investigate interictal cerebral blood flow (CBF) distributions and graph theoretical networks in idiopathic generalized epilepsy (IGE) using arterial spin labeling (ASL) imaging and anatomical covariance methods of graph theoretical analysis. Material and methodsWe recruited 19 patients with IGE and 19 age-/gender-matched healthy controls. Their CBF images were obtained by pseudo-continuous ASL imaging and compared using statistical parametric mapping 8 software (SPM8) and Graph Analysis Toolbox (GAT). ResultsThe ASL imaging could detect interictal hypoperfusion in the thalamus, upper midbrain, and left cerebellum in IGE. Additionally, the graph theoretical analyses revealed characteristic findings of the CBF network of IGE, including significantly reduced resilience to attacks and changes of regional clustering especially in the bilateral temporo-occipital areas and lateral frontal lobes. There was no significance in the comparisons of network metrics. ConclusionThese findings could contribute to a better understanding of the pathophysiology of IGE.

P036 Defective interhemispheric inhibition in focal epilepsies

Question Focal epilepsies (FEs) arise from a lateralized network. In generalized epilepsies (GEs) there is a bilateral network involvement from the outset. The corpus callosum is the anatomical substrate for interhemispheric spread, although its detailed physiological role is uncertain. We used transcranial magnetic stimulation (TMS) to explore the physiology of the corpus callosum in patients with FE and idiopathic GE (IGE), as compared to healthy subjects (HS). Methods We studied 16 patients with FE, 17 with IGE, and 17 HS of similar age and sex. We used TMS to measure the interhemispheric inhibition (IHI) from left-to-right primary motor cortex (M1) and viceversa. A conditioning stimulus (CS) was given to one M1 10 and 50 ms before a test stimulus delivered to the contralateral M1. Statistics was based on ANOVAs. Results Across HS, IHI was reproducible, since a contralateral CS suppressed MEPs at ISIs of 10 and 50 ms ( p p p Conclusions FE patients had a bilateral defective inhibitory response. We suggest that it may represent one key factor for the contralateral spread of focal discharges, and seizure generalization.

Dynamic functional network connectivity in idiopathic generalized epilepsy with generalized tonic-clonic seizure.

Idiopathic generalized epilepsy (IGE) has been linked with disrupted intra-network connectivity of multiple resting-state networks (RSNs); however, whether impairment is present in inter-network interactions between RSNs, remains largely unclear. Here, 50 patients with IGE characterized by generalized tonic-clonic seizures (GTCS) and 50 demographically matched healthy controls underwent resting-state fMRI scans. A dynamic method was implemented to investigate functional network connectivity (FNC) in patients with IGE-GTCS. Specifically, independent component analysis was first carried out to extract RSNs, and then sliding window correlation approach was employed to obtain dynamic FNC patterns. Finally, k-mean clustering was performed to characterize six discrete functional connectivity states, and state analysis was conducted to explore the potential alterations in FNC and other dynamic metrics. Our results revealed that state-specific FNC disruptions were observed in IGE-GTCS and the majority of aberrant functional connectivity manifested itself in default mode network. In addition, temporal metrics derived from state transition vectors were altered in patients including the total number of transitions across states and the mean dwell time, the fraction of time spent and the number of subjects in specific FNC state. Furthermore, the alterations were significantly correlated with disease duration and seizure frequency. It was also found that dynamic FNC could distinguish patients with IGE-GTCS from controls with an accuracy of 77.91% (P < 0.001). Taken together, this study not only provided novel insights into the pathophysiological mechanisms of IGE-GTCS but also suggested that the dynamic FNC analysis was a promising avenue to deepen our understanding of this disease. Hum Brain Mapp 38:957-973, 2017. © 2016 Wiley Periodicals, Inc.

Altered Effective Connectivity among Core Neurocognitive Networks in Idiopathic Generalized Epilepsy: An fMRI Evidence.

Idiopathic generalized epilepsy (IGE) patients with generalized tonic-clonic seizures (GTCS) suffer long-term cognitive impairments, and present a higher incidence of psychosocial and psychiatric disturbances than healthy people. It is possible that the cognitive dysfunctions and higher psychopathological risk in IGE-GTCS derive from disturbed causal relationship among core neurocognitive brain networks. To test this hypothesis, we examined the effective connectivity across the salience network (SN), default mode network (DMN), and central executive network (CEN) using resting-state functional magnetic resonance imaging (fMRI) data collected from 27 IGE-GTCS patients and 29 healthy controls. In the study, a combination framework of time domain and frequency domain multivariate Granger causality analysis was firstly proposed, and proved to be valid and accurate by simulation experiments. Using this method, we then observed significant differences in the effective connectivity graphs between the patient and control groups. Specifically, between-group statistical analysis revealed that relative to the healthy controls, the patients established significantly enhanced Granger causal influence from the dorsolateral prefrontal cortex to the dorsal anterior cingulate cortex, which is coherent both in the time and frequency domains analyses. Meanwhile, time domain analysis also revealed decreased Granger causal influence from the right fronto-insular cortex to the posterior cingulate cortex in the patients. These findings may provide new evidence for functional brain organization disruption underlying cognitive dysfunctions and psychopathological risk in IGE-GTCS.

Circadian phase typing in idiopathic generalized epilepsy : dlmo and patterns of melatonin secretion semicurve findings in adult patients

Circadian phase typing in idiopathic generalized epilepsy : dlmo and patterns of melatonin secretion semicurve findings in adult patients

A computational biomarker of idiopathic generalized epilepsy from resting state EEG.

SummaryEpilepsy is one of the most common serious neurologic conditions. It is characterized by the tendency to have recurrent seizures, which arise against a backdrop of apparently normal brain activity. At present, clinical diagnosis relies on the following: (1) case history, which can be unreliable; (2) observation of transient abnormal activity during electroencephalography (EEG), which may not be present during clinical evaluation; and (3) if diagnostic uncertainty occurs, undertaking prolonged monitoring in an attempt to observe EEG abnormalities, which is costly. Herein, we describe the discovery and validation of an epilepsy biomarker based on computational analysis of a short segment of resting‐state (interictal) EEG. Our method utilizes a computer model of dynamic networks, where the network is inferred from the extent of synchrony between EEG channels (functional networks) and the normalized power spectrum of the clinical data. We optimize model parameters using a leave‐one‐out classification on a dataset comprising 30 people with idiopathic generalized epilepsy (IGE) and 38 normal controls. Applying this scheme to all 68 subjects we find 100% specificity at 56.7% sensitivity, and 100% sensitivity at 65.8% specificity. We believe this biomarker could readily provide additional support to the diagnostic process.