EEG recording after sleep deprivation in a series of patients with juvenile myoclonic epilepsy

Abstract

-Seizures in Juvenile Myoclonic Epilepsy (JME) are dependent on the sleep-wake cycle and precipitant factors, among which sleep deprivation (SD) is one of the most important. Still an under diagnosed syndrome, misinterpretation of the EEGs contributes to diagnostic delay. Despite this, a quantitative EEG investigation of SD effects has not been perf o rmed. We investigated the effect of SD on EEGs in 41 patients, aged 16-50 yr. (mean 25.4), who had not yet had syndromic diagnosis after a mean delay of 8.2 yr. Two EEG recordings separated by a 48-hour interval were taken at 7 a.m. preceded by a period of 6 hours of sleep (routine EEG) and after SD (sleep-deprived EEG). The same protocol was followed and included a rest wakefulness recording, photic stimulation, hyperventilation and a post-hyperventilation period. The EEGs were analyzed as to the effect of SD on the number, duration, morphology, localization and pre d ominance of abnormalities in the diff e rent stages. A discharge index (DI) was calculated. Out of the 41 patients, 4 presented both normal EEG recordings. In 37 (90.2%) there were epileptiform discharges (ED). The number of patients with ED ascended from 26 (70.3%) in the routine EEG to 32 (86.5%) in the sleep-deprived exam. The presence of generalized spike-wave and multispike-wave increased from 20 (54.1%) and 13 (35.1%) in the first EEG to 29 (78.4%) and 19 (51.4%) in the second, respectively (p<0.05 and p<0.01). As to localization, the number of generalized, bilateral and synchronous ED increased from 21 (56.8%) to 30 (81.1%) (p<0.01). The DI also increased; while 8 patients (21.6%) presented greater rate in the routine EEG, 25 (67.6%) did so in the sleep-deprived EEG mainly during somnolence and sleep (p<0.01). Moreover, the paroxysms were also longer in the sleep-deprived EEG. Sleep-deprived EEG is a powerful tool in JME and can contribute significantly to the syndromic characterization of this syndrome.KEY WORDS: sleep deprivation, EEG diagnosis, juvenile myoclonic epilepsy.Registros eletrencefalográficos após privação de sono em uma série de pacientes com epilepsia mioclônica juvenil RESUMO -Na epilepsia mioclônica juvenil (EMJ), uma síndrome epiléptica ainda subdiagnosticada, as crises são dependentes do ciclo vigília-sono e de fatores precipitantes, entre os quais a privação de sono (PS) é um dos mais importantes. A interpretação inadequada dos EEGs contribui para atraso no diagnóstico. Ainda não foi realizada investigação quantitativa sobre os efeitos da PS. Avaliamos o efeito da PS nos EEGs de 41 pacientes entre 16 e 50 anos (média 25,4) com EMJ em dois registros eletrencefalográficos, separados por intervalo de 48 horas. Os exames foram realizados às 7 horas da manhã, precedidos por um período de 6 horas de sono (EEG de rotina) e após PS (EEG com PS). Seguimos o mesmo protocolo que incluiu o registro em vigília em repouso, fotostimulação, hiperventilação e pós hiperventilação. O efeito da PS foi analisado sobre o número, duração, morfologia, localização e predominância das anor...

Juvenile myoclonic epilepsy

“…They may be isolated spikes, sharp waves, slow waves, or spike-and-wave complexes 7,16,21 . Asymmetry of the recording was found in 9.8-33.3% of cases 1,19,21 , and its frequency was increased in EEGs with sleep deprivation 25 . Hyperventilation made the EEG abnormalities more obvious in all patients that were analyzed by Panayiotopoulos et al 7 .…”

“…The main alternative pattern is generalized and irregular spike-and-wave (3-5 Hz), reported among 25.2-78.4% of cases 6,19 . In addition, the clinician may fi nd slow sharp waves, bursts of slow waves, groups of sharp waves, groups of spikes, and a fast rhythm 25 . Focal discharges were more frequent in the frontal regions 19,25 .…”

“…In addition, the clinician may fi nd slow sharp waves, bursts of slow waves, groups of sharp waves, groups of spikes, and a fast rhythm 25 . Focal discharges were more frequent in the frontal regions 19,25 . They may be isolated spikes, sharp waves, slow waves, or spike-and-wave complexes 7,16,21 .…”

Primary Sleep Disorders in People with Epilepsy

“…153 The mean number and duration of IEDs during sleep and on awakening has been shown to increase in JME after SD. 154 Recommendations to have sufficient sleep and maintain regular bedtimes often go unheeded in patients with JME. Why unheeded given the dire consequences?…”

Juvenile myoclonic epilepsy: Under-diagnosed syndrome

“…Broj šiljaka u jednom kompleksu varira 5-20 i u pozitivnoj je korelaciji sa intenzitetom mioklonija. Šilj-ci su generalizovani, skoro uvek simetrični, visoke frekvencije (10-16 Hz), obično praćeni sporim talasom frekvencije 2,5-5 Hz [31,32] . Na iktalnom EEG-u se mogu registrovati i klasični, pravilno formirani šiljak-talas kompleksi od 3 Hz, obično udruženi sa apsansima.…”