Efficacy and safety of a video-EEG protocol for genetic generalized epilepsies.

INTRODUCTION: Video-EEG has been used to characterize genetic generalized epilepsies (GGE). For best performance, sleep recording, photic stimulation, hyperventilation, and neuropsychological protocols are added to the monitoring. However, risks and benefits of these video-EEG protocols are not well established. The aim of this study was to analyze the efficacy and safety of a video-EEG neuropsychological protocol (VNPP) tailored for GGE and compare its value with that of routine EEG (R-EEG). METHODS: We reviewed the VNPP and R-EEG of patients with GGE. We considered confirmation of the clinical suspicion of a GGE syndrome and characterization of reflex traits as benefits; and falls, injuries, psychiatric and behavioral changes, generalized tonic-clonic (GTC) seizures, and status epilepticus (SE) as the main risks of the VNPP. RESULTS: The VNPPs of 113 patients were analyzed. The most common epileptic syndrome was juvenile myoclonic epilepsy (85.8%). The protocol confirmed a GGE syndrome in 97 patients and 62 had seizures. Sleep recording had a provocative effect in 51.2% of patients. The second task that showed highest efficacy was praxis (39.3%) followed by hyperventilation (31.3%). Among the risks, 1.8% had GTC seizures and another 1.8%, SE. Eighteen percent of patients had persistently normal R-EEG, 72.2% of them had discharges during VNPP. Generalized tonic-clonic seizures, myoclonic status epilepticus, and repeated seizures were the main risks of VNPP present in 6 (5.31%) patients while there were no complications during R-EEG. CONCLUSIONS: The VNPP in GGE is a useful tool in diagnosis and characterization of reflex traits, and is a safe procedure. Its use might preclude multiple R-EEG exams.

Prognosis of Juvenile myoclonic epilepsy with eye-closure sensitivity.

PURPOSE: Eye closure sensitivity (ECS) has been described as a reflex trait in juvenile myoclonic epilepsy (JME). However, there is no consensus regarding its significance on prognosis. The aim of this study is to clarify the long-term impact of ECS documented by a clinical interview and a video-EEG neuropsychological protocol (VNPP) in a series of 133 JME patients. METHODS: Data from 22 JME patients with ECS confirmed by a VNPP (Group 1) were compared with those of 20 JME patients without any reflex traits (Group 2). They were followed for a mean of 8.21 years (SD=±5.044). The frequency of seizures was assessed using a diary. Except for photosensitivity (PS), any other reflex traits occurrence, drugs/alcohol abuse intake, noncompliance, and Jeavons syndrome, were considered exclusion criteria. RESULTS: Group 1 had a lower age at epilepsy onset (p = 0.028), higher incidence of febrile seizures (13.6%), and familial history of epilepsy (p = 0.023). Only 18.2% had self-perception of eyelid myoclonia (EM) (kappa coefficient = 0.193), which persisted in 77.3% of patients. Limb myoclonia, tonic-clonic seizures (TCS) and/or myoclonic-tonic-clonic seizures (MTCS), as well as absences were more frequent (p = 0.015; p = 0.013; p = 0.011, respectively) in Group 1. PS did not influenced frequency of EM (p = 1.0), absences (p = 0.648), or TCS/MTCS (p = 0.934). Psychiatric comorbidities were not different between groups. CONCLUSIONS: ECS is related to a worse outcome regarding control of all seizure types, persistence of EM, and higher frequency of limb myoclonia, as well as the total number of TCS and/or MTCS.

Cognitive performance in juvenile myoclonic epilepsy patients with specific endophenotypes.

PURPOSE: Juvenile myoclonic epilepsy (JME) is a heterogeneous syndrome in which seizures can be precipitated not only by non-specific factors, such as sleep deprivation and stress, but also by specific stimuli, such as photic stimuli, eye-closure, praxis, and language. The presence of these reflex traits may indicate the hyperexcitability of different cortical areas, which may be reflected in patients' neuropsychological deficit profile. The objective of our study is to investigate the possible relations between JME endophenotypes and patients' cognitive performance. METHODS: 61 JME patients were divided into four groups: no reflex traits (group 1, 20 patients); praxis induction (group 2, 13); eye-closure and/or photosensitivity (group 3, 17); and a combination of different reflex traits (group 4, 11). Neuropsychological performance was compared between JME subgroups. 60 healthy controls were used to calculate z-scores. Patients also underwent psychiatric assessment. We controlled the clinical variables, e.g. age at epilepsy onset, frequency of myoclonic seizures, total and sedative drug load, setting them as covariables for the ANOVA analysis. RESULTS: Praxis induction was more common in males (p=0.018) and groups with reflex traits (2, 3, and 4) presented higher rates of persistent myoclonia, polytherapy, clonazepam use (group 3), and more frequent psychiatric comorbidities. Group 4 patients performed worse in Trail Making Test B than the patients in group 1. These findings were independent of clinical variables. CONCLUSION: JME patients with a combination of praxis induction and eye-closure/photosensitivity had greater executive dysfunction, revealing an association between reflex ictogenic mechanisms and cognitive performance.

Phenotyping juvenile myoclonic epilepsy. Praxis induction as a biomarker of unfavorable prognosis.

PURPOSE: Juvenile myoclonic epilepsy (JME) is a heterogeneous syndrome with seizures presenting typical fluctuation in diurnal cycle and relation with awakening. Few publications have approached clinical expressions of praxis induction (PI) in the nosology of JME as well as its impact on outcome. The aim of this study is to characterize PI as the only reflex trait in JME and its relation with prognosis. METHOD: JME with PI reported on a questionnaire and confirmed by video-EEG testing (Group 1, 20 patients) were compared with JME without any reflex epileptic trait (Group 2, 25 patients) and followed for a mean of 7.82 years (SD=3.98). Circadian distribution and frequency of seizures were assessed in a diary. Patients also had psychiatric evaluation. RESULTS: Prevalence of PI was 20/133 (15%) JME patients, and was predominant in males (1.5 male: 1 female; OR 13; p=0.042). Among Group 1 patients, only 2/20 presented seizures exclusively in the morning (p=0.013), and none, exclusively on awakening (p<0.001). PI patients had worse prognosis regarding control of myocloni (p=0.02) and absences (p=0.01); only 7/20 (35.0%) could be treated with VPA in monotherapy (p=0.01). At the last follow-up, 2/20 (10.0%) of Group 1 and 10 (40.0%) of Group 2 patients were free of all three seizure types (p=0.02). Even though relative risk of stress as a precipitant of seizures increased 3.82 times in Group 1, psychiatric comorbidities were not different between groups. CONCLUSION: PI reflex trait in JME is related to seizures without preferential circadian occurrence and reduced response to antiepileptic drugs.

Blinking and eyelid myoclonia: Characteristics and correlations of eyelid movements.

PURPOSE: Eyelid myoclonia (EM) is considered a seizure type and has been described in several epileptic conditions. Previous studies reported that EM are precipitated only by slow eye closure, but little is known about the characteristics of blinking in patients with EM seizures and differences in precipitation of EM by different kinds of eye closure. We analyzed by video-EEG the characteristics of blinking and eye closure in these patients. METHOD: Twenty patients with EM had a video-EEG protocol with eyelid sensors. Semiology and rate of blinking and EM were analyzed. Statistical analysis was performed and p-values <0.05 were considered significant. RESULTS: Seventeen cases (mean age 20.7, range 3-35) were women, 10 had EM as the main seizure type and between the others, all, but one, had criteria to Juvenile Myoclonic Epilepsy. All patients presented EM, 18 spontaneously during awake, 10 on eye closure and one only during intermittent photic stimulation. EM assumed the form of flicker, flutter or jerk, accompanied by generalized discharges, spiky posterior alpha, theta rhythm or absence of any EEG abnormality. Analysis of the characteristics of blinking had no statistics differences between patients and healthy subjects. The rate of blinks and EM increased during speech and decreased during reading. EM never occurred during blinking or in the dark. CONCLUSIONS: Despite normal physiology of blinking, EM can manifest as jerk, flicker or flutter, with or without EEG abnormalities and independently of IPS, suggesting that eye closure sensitivity seems to include both, a motor and a visual component.

Does the patient's hand hold the key to preventing secondary generalization in mesial temporal lobe epilepsy?

This study aimed to analyze the impact of ictal dystonic posturing (DP) in postoperative seizure outcome and to assess the influence of DP in generalized tonic-clonic seizure (GTCS) occurrence during video-EEG monitoring of patients with temporal lobe epilepsy with mesial temporal sclerosis. The impact of DP on surgical outcome remains controversial. Moreover, DP has been recently associated with brain networks avoiding GTCS occurrence. Five hundred twenty-seven seizures of 171 patients who were submitted to standard anterior temporal lobectomy (ATL) between 2002 and 2010, with at least one year of post-surgical follow-up, were retrospectively analyzed and classified as with or without DP and as evolving or not to GTCS. The ictal semiologic correlates of DP, timing elapsed since precedent seizure and antiepileptic drug (AED) intake before each seizure were evaluated. Seizure outcome after ATL was assessed according to Engel's scale. Fifty-eight out of 171 patients (34%) exhibited ictal DP, of which 91.5% were always unilateral and contralateral to the operated side. DP was related to shorter seizures (p=0.007) and a much lower likelihood of the seizure evolving to GTCS (p=0.001), even during AED withdrawal (p=0.002). There was no association between DP and prognosis regarding seizure control as the result of the surgical resection, either in patients with shorter or in those with longer period of follow-up. Our data support the hypothesis that DP reflects a brain network activation that helps avoid GTCS, even during AED withdrawal.

Estimulação fótica: padronização do método de acordo com o consenso europeu: [revisão] / Photic stimulation: standardization of the method based on european consensus: [review]

INTRODUÇÃO: Embora a fotostimulação intermitente (FEI) seja rotineiramente utilizada nos laboratórios de eletrencefalografia (EEG), raramente é utilizada de forma padronizada. A FEI é um método de ativação utilizado no EEG de rotina que pode desencadear tanto respostas fisiológicas quanto potencialmente patológicas. Historicamente, o termo fotossensibilidade se refere às respostas anormais à estimulação com luz estroboscópica durante o registro do EEG. OBJETIVO: O objetivo desta publicação é revisar os aspectos diagnósticos do procedimento da FEI, baseados no encontro de consenso realizado em Heemstede na Holanda, em 1996, com o propósito de facilitar e padronizar a detecção de pacientes fotossensíveis.

INTRODUCTION: Although intermittent photic stimulation (IPS) is a widespread and routinely used procedure in EEG laboratories, only relatively recently has a standardization of the IPS method been proposed. IPS is an activation method used during EEG procedure that may trigger either physiological or potentially pathological responses. Historically, the term photosensitivity is referred to abnormal responses to stroboscopic light during EEG. OBJECTIVE: The purpose of this publication was to provide an overview of the diagnostic aspects of IPS procedure, based on data presented at Consensus Meetings held in Heemstede, the Netherlands, in 1996, with the purpose of facilitating the detection of photosensitive patients.