Epileptic Encephalopathies with Status Epilepticus during Sleep: New Techniques for Understanding Pathophysiology and Therapeutic Options

Abstract

Encephalopathy with status epilepticus during sleep (ESES) is an epileptic encephalopathy, as defined by the International League Against Epilepsy (ILAE) Task Force on Classification and Terminology, that is, a condition in which the epileptic processes themselves are believed to contribute to the disturbance in cerebral function. Clinical manifestations of ESES are heterogeneous: apart from different seizure types, they consist in combinations of cognitive, motor, and behavioural disturbances associated with a peculiar electroencephalographic pattern of paroxysmal activity significantly activated during slow sleep, which culminates in a picture of continuous spikes and waves during sleep (CSWS). The pathophysiological mechanisms underlying this condition are still incompletely understood. Establishing a clear-cut correlation between EEG abnormalities and clinical data, though interesting, is very complex. Computer-assisted EEG analyses especially if combined with functional magnetic resonance imaging (EEG-fMRI) and metabolic neuroimaging have recently emerged as useful approaches to better understand the pathophysiological processes underlying ESES. Treatment of ESES is not just limited to seizures control but it should be focused on controlling neuropsychological outcome through an improvement of the continuous epileptiform activity. General agreement on treatment guidelines is still lacking. Implementation of new techniques might allow a better understanding of the pathophysiology of ESES and could enhance therapeutics options.

Continuous Spikes and Waves during Sleep: Electroclinical Presentation and Suggestions for Management

“…There is evidence in the literature supporting a beneficial effect of treatment on seizure frequency and severity [7, 19, 26, 36, 66–70] and epileptiform activity [19, 21, 71, 72]. Several studies suggest that long-term neurocognitive function can significantly improve once epileptiform discharges are reduced, and this effect has been related to treatment with antiepileptic drugs [3, 6, 7, 17, 19, 73–77]. However, to date, there is no scientific evidence for or against treatment of interictal spikes.…”

Long‐term evolution of neuropsychological competences in encephalopathy with status epilepticus during sleep: A variable prognosis

“…A possible interpretation is the recognition of an underlying disease. However, this finding may also reflect a limitation of our study, which did not use the new techniques of cortical EEG sources (Brazzo et al., ).…”

Corticosteroid therapy for epileptic encephalopathies other than West syndrome

“…This pattern is typical but not specific for LKS, as it could be present, for example, in opercular syndromes or in patients after ventriculoperitoneal shunt surgery for hydrocephalus [55,56]. Although the most plausible hypothesis establishes a correlation between interictal EEG activity and neuropsychological impairment, a direct relationship has yet to be clearly established; new functional imaging techniques seem to be useful in understanding the pathophysiological processes underlying ESES/CSWS [57,58]. Neuropsychological alterations are a fundamental element in diagnosing the syndrome and they appear to be related to the predominant focality of discharges, such as temporal in language impairment or frontal in behavioral disturbances [53,[59][60][61].…”