Continuous Spike and Waves During Sleep and Electrical Status Epilepticus in Sleep

Abstract

Continuous spike and waves during sleep is an age-related epileptic encephalopathy that presents with neurocognitive regression, seizures, and an EEG pattern of electrical status epilepticus during sleep. Patients usually present around 5 years of age with infrequent nocturnal unilateral motor seizures that progress within 1 to 2 years to a severe epileptic encephalopathy with frequent seizures of different types, marked neurocognitive regression, and an almost continuous spike-wave EEG pattern during slow-wave sleep. The pathophysiology of continuous spike and waves during sleep is not completely understood, but the corticothalamic neuronal network involved in physiologic oscillating patterns of sleep is thought to be switched into a pathologic discharging mode. Early developmental injury and/or genetic predisposition may play a role in the potentiation of age-related hyperexcitability in the immature brain. A better understanding of the mechanisms leading to electrical status epilepticus during sleep may provide additional therapeutic targets that can improve the outcome of seizures, EEG pattern, and cognitive development in patients with continuous spike and waves during sleep.

Encephalopathy with Electrical Status Epilepticus in Slow Wave Sleep – a review with an emphasis on regional (perisylvian) aspects

“…According to Loddenkemper et al (2011) fine and gross motor skills may also be observed. Dystonia, dyspraxia, ataxia, and unilateral Several studies attempted to correlate nuropsychological deficits in chidhood regional idiopathic hyperexcitability syndromes.…”

“…Not only the electro-morphology was considered to be "spike-and-wave" but the recent interpretations about the pathomechanism of the discharges also went back to the classical generalized spike wave pattern. For example, Loddenkemper et al (2011) and Sánchez Fernández et al (2012) trying to explain the association of ESES and early thalamic lesion, refer to the Steriade model of spike-wave network, related to the interrelationships within the cortico-thalamic system. Similarly, Tassinari et al (2012) relies on the secondary bilateral synchrony mechanism which was assumed to work classically (Tükel and Jasper, 1952) by involving secondarily thalamic and thalamo-cortical circuitry.…”

“…Usually there are no residual deficits when the period of discharging is shorter than 13 months and it develops as a rule when it persists for more than 18 months (Garcia-Penas, 2010;Kramer et al, 2009). At least 50% of patients remain severely impaired (Loddenkemper et al, 2011;Tassinari et al, 2000;Nickels and Wirelli, 2008). A good correlation exists between the cortical localisation of discharges and the disrupted function (Tassinari et al, 2009).…”

“…The discharge amount is usually higher in the first sleep cycle and progressively decreases through the night. A modification of this measure is to count spike frequency expressed as the number of spikes per time interval, which seems to be more sensitive (Loddenkemper et al, 2011). Measuring spike frequency during sleep and wakefulness, and comparing the differences between them, provides a measure for sleep potenciation factor (Sánches Fernández, 2012).…”

“…During the almost 45 year history of this topic the unresolved questions around the syndrome came closer to research problems as how sleep activates epilepsy, how epilepsy interferes with cognitive functioning and how sleep plays a role in plastic functions. In recent years there has been a large increase in interest toward ESES/CSWS and several excellent reviews and summaries have been published (Loddenkemper et al, 2011;Tassinari et al, 2012;Sánchez Fernández et al, 2012). An international conference on Encephalopathy with Electrical Status Epilepticus during Slow Sleep was also held in March, 2014 in Soro (Denmark).…”