The complementary value of sleep-deprived EEG in childhood onset epilepsy.

BACKGROUND

Although EEG is an important diagnostic tool in suspected childhood onset epilepsy, as many as 50% of wakefulness records remain normal. Sleep-deprived EEG has been reported in adults to serve as an activator of epileptic discharges but such effect is still not agreed upon in children reporting small series.

PURPOSE

Assess the complementary diagnostic value of sleep deprivation on the induction of epileptic discharges in childhood onset epilepsy having a normal awake record within a period of 5 years. EEG recording was performed during the awake, drowsiness and sleep states following sleep deprivation of 6h. BACKGROUND RESULTS: Fifty five children of whom the initial record failed to detect epileptiform discharges, were assessed at age 5-17 years (mean: 10+/-3.7), 27 boys and 28 girls. Sleep occurred in 51 (92.7%) after sleep deprivation and in only 1 (1.8%) during an awake record. Epileptic discharges were detected in 15 of 55 (27.2%) previous non-epileptic awake records during the sleep-deprived EEG either during wakefulness and more frequent during sleep. Eight abnormal records were detected in 18 (44%) children presenting with a focal seizure and 7 of 35 (20%) associated with generalized seizures. Epileptic discharges were recorded mainly and more frequent during sleep.

CONCLUSIONS

Our data suggests that sleep deprivation imposes an apparent activating impact uncovering epileptic discharges children corroborating with overt clinical seizures even beyond the sampling effect of repeat records.