Neurophysiology of CSWS-associated cognitive dysfunction

The phenomenon of continuous spikes and waves during slow-wave sleep (CSWS) is associated with a number of epileptic syndromes, which share a behavioral phenotype characterized by deterioration of cognitive, behavioral, or sensorimotor functions. Available evidence seems to suggest that spike-wave activity is a result of a complex interaction between cortical and subcortical inhibitory networks and can "per se" produce a transient loss of underlying cortical functions. Syndromes like Landau-Kleffner syndrome, CSWS, and phenomena such as negative myoclonus could share in common--at least at the neurophysiological level--some similarities. Differences in behavioral phenotypes could be explained in term of maturational and genetic differences, as well as by the functional specificity of the involved areas

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

PURPOSE: The aim of this study was to evaluate the long-term cognitive outcome in children with continuous spikes and waves during slow wave sleep (CSWS syndrome). METHODS: We reviewed the neuropsychological tests of 25 children diagnosed with CSWS between 1987 and 2010 and with a mean follow-up of 13.5 years. KEY FINDINGS: Cognitive performances worsened during CSWS in virtually all patients. Seven patients (28%) with nonlesional epilepsy had a positive outcome; three patients (12%) showed persistence of motor deficit without involvement of cognitive functions; and seven patients (28%) who presented a long duration of CSWS (mean = 28.1 months) had a negative cognitive outcome. In 6 patients (24%) with structural or metabolic disorders before CSWS onset cognitive outcomes did not change; 2 patients (8%) had a negative outcome irrespective of the duration or presence of other neurologic disorders before CSWS onset. Forty-four percent of children with CSWS demonstrated permanent cognitive impairment. SIGNIFICANCE: The long-term outcome of CSWS syndrome is variable and seems to depend on treatment response, disease duration, and underlying etiology

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

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

Therapy of encephalopathy with status epilepticus during sleep (ESES/CSWS syndrome) : an update

Electrical status epilepticus in sleep (ESES)/continuous spikes and waves during slow sleep (CSWS) is an age-related, self-limiting disorder characterised by epilepsy with different seizure types, global or selective neuropsychological regression, motor impairment, and a typical EEG pattern of continuous epileptiform activity for more than 85% of non-rapid eye movement (NREM) sleep. Although the first description of ESES/CSWS dates back to 1971, an agreement about the optimal treatment for this condition is still lacking. ESES/CSWS is rare (incidence is 0.2-0.5% of all childhood epilepsies) and no controlled clinical trials have been conducted to establish the efficacy of different antiepileptic drugs; only uncontrolled studies and case reports are reported in the literature. Treatment options for ESES/CSWS include some antiepileptic drugs (valproic acid, ethosuximide, levetiracetam, and benzodiazepines), steroids, immunoglobulins, the ketogenic diet, and surgery (multiple subpial transections). In this study, the comparative value of each of these treatments is reviewed and a personal therapeutic approach is propose

Therapy of encephalopathy with status epilepticus during sleep (ESES/CSWS syndrome): an update

Electrical status epilepticus in sleep (ESES)/continuous spikes and waves during slow sleep (CSWS) is an age-related, self-limiting disorder characterised by epilepsy with different seizure types, global or selective neuropsychological regression, motor impairment, and a typical EEG pattern of continuous epileptiform activity for more than 85% of non-rapid eye movement (NREM) sleep. Although the first description of ESES/CSWS dates back to 1971, an agreement about the optimal treatment for this condition is still lacking. ESES/CSWS is rare (incidence is 0.2-0.5% of all childhood epilepsies) and no controlled clinical trials have been conducted to establish the efficacy of different antiepileptic drugs; only uncontrolled studies and case reports are reported in the literature. Treatment options for ESES/CSWS include some antiepileptic drugs (valproic acid, ethosuximide, levetiracetam, and benzodiazepines), steroids, immunoglobulins, the ketogenic diet, and surgery (multiple subpial transections). In this study, the comparative value of each of these treatments is reviewed and a personal therapeutic approach is propose

Interictal autonomic abnormalities in idiopathic Rolandic epilepsy

We investigated 50 young patients with a diagnosis of Rolandic Epilepsy (RE) for the presence of abnormalities in autonomic tone compared with 50 young patients with idiopathic generalized epilepsy with absences and 50 typically developing children of comparable age. We analyzed time domain (N-N interval, pNN50) and frequency domain (High Frequency (HF), Low Frequency (LF) and LF/HF ratio) indices from ten-minute resting EKG activity. Patients with RE showed significantly higher HF and lower LF power and lower LF/HF ratio than controls, independent of the epilepsy group, and did not show significant differences in any other autonomic index with respect to the two control groups. In RE, we found a negative relationship between both seizure load and frequency of sleep interictal EEG abnormalities with parasympathetic drive levels. These changes might be the expression of adaptive mechanisms to prevent the excessive sympathetic drive seen in patients with refractory epilepsies