Abstracts

Rationale: Electrical Status Epilepticus of Sleep (ESES) is an electrographic pattern characterized by continuous, diffuse, 1.5 to 3 Hertz spike and slow wave complexes during slow wave sleep. ESES is associated with either focal or generalized epilepsy, neuropsychological impairment, such as cognitive regression, acquired aphasia (Landau-Kleffner syndrome), visual agnosia, epileptic dysgraphia, progressive prosopagnosia, or motor impairments with ataxia or dyspraxia. The diagnostic criteria for ESES have been debated: especially the abundance of spike activity required for the diagnosis, what “continuous” means, must it involve slow wave sleep, whether it is an epiphenomenon or if focal ESES even exists? We postulate that the region involved determines the clinical impairments seen with focal ESES and suggest the term electrical epilepsia partialis continua of sleep (EEPCS) when the epileptiform activity is predominantly focal within the ESES. Methods: We describe five children with focal ESES with motor, cognitive, speech, and visual problems related to the cortical region involved. Neurocognitive regression was prominent in all.Results: An 8-year-old girl had a left MCA territory stroke, right hemiparesis, right visual field cut, and focal and diffuse left hemisphere ESES with cognitive/behavioral difficulties that responded to high dose diazepam, levetiracetam, and zonisamide, but ultimately required hemispherectomy . A 12-year-old boy with a left MCA territory stroke had a right hemiparesis, complex partial seizures, cognitive/attention difficulties, and predominantly focal ESES (left frontal/parietal) that failed multiple treatments but then responded to levetiracetam. An 18-year-old girl with left frontal-central encephalomalacia, complex partial epilepsy, cognitive, memory/ attention difficulties associated with initially ESES that evolved into focal ESES (left frontal, central and midline central) after treatment, responded to corticosteroids and vagus nerve stimulation. An 11-year-old girl with periventricular leukomalacia, spastic quadriparesis, generalized epilepsy, and cognitive/behavioral difficulties, initially with generalized ESES which, upon treatment, evolved into focal ESES (bilateral left > right frontal then left > right occipital), had a response to sodium valproate and levetiracetam. An 8-year-old boy with a history of intraventricular hemorrhage, periventricular leukomalacia, spastic quadriparesis, generalized epilepsy, and focal ESES (left > right occipital) had cognitive and visual difficulties that responded to treatment with high dose diazepam. Conclusions: Focal-ESES or EEPCS is characterized by focal paroxysmal activity during slow wave sleep and is usually associated with neurological or neuropsychological symptoms related to the cortical region involved. Overall regression occurs when the activity generalizes. Both the EEPCS and clinical impairments may improve with suppression or elimination of the epileptiform activity by spike-suppressors, even with underlying structural disorders.