HP27: Continuous spike-waves during slow-wave sleep (CSWS): An electroclinical evaluation according to the EEG patterns

Abstract

To determine a possible association between clinical manifestations and EEG characteristics of CSWS patients. Introduction: CSWS is a rare condition that occurs only in children and adolescents, characterized by a distinctive electroencephalogram (EEG) and heterogeneous clinical manifestations. Aims: To determine a possible association between clinical manifestations and EEG characteristics of CSWS patients. Methods: We reviewed data of 12 pediatric patients who received a sleep EEG showing near-continuous spike-wave (SW) discharge (>50%) on a poorly organized sleep pattern. We defined the CSWS pattern as anterior if the maximum amplitude and/or the start of the SW were frontal, fronto-central or fronto-temporal and as posterior if the maximum amplitude and/or the start of the SW were temporal, temporo-occipital or occipital on the EEG. Results: The study included 12 patients (58% male) with a mean age of 4,6 years. Seven children had an anterior pattern with motor seizures in 3 cases and loss of contact in 4 cases. Five children had a posterior pattern with sensory motor seizures, loss of contact, aphasia in 1 case each and motor seizure in 2 cases. All the children presented cognitive abnormalities. Conclusion: The association between the EEG pattern of CSWS and clinical manifestations is controversial but remains a hypothesis to be awakened.