Abstracts

Rationale: Background Electrodecremental activity (EDA) in the EEG has been described in infantile spasms, tonic and atonic seizures and it has been considered to reflect a cortical and brainstem disorder. There are no studies in Latin America describing the electro clinical association of EDA in pediatric patients. Objective Describe the clinical patterns associated with EDA in pediatric patients. Methods: Methods EDA was defined as the pattern of fast activity of low voltage with less than 25mV and a frequency higher than 15Hz or by diffuse flattening without fast activity. We included 37 patients between 5 months and 17 years old valued at the Department of Electrophysiology between June 2009 and December 2011. We reviewed the video EEG records describing the clinical pattern associated with EDA, associated seizure types and discharges, correlating age and diagnosis. Results: Results We observed predominance of tonic seizures (27%) and flexion spasms (24%) associated with EDA, also describing motor arrest (14%), drop head (5.5%) and absence seizures (5.5%). The EDA was mostly associated with slow wave pattern (43%). The predominant etiology was hypoxic - ischemic (55%), being associated with Lennox Gastaut syndrome in 16.5% and West syndrome in 13.5%. Conclusions: Conclusions The EDA is not exclusive of tonic events and infantile spasms and can also be associated with motor arrest, drop head and absence seizures, considering such associations as heraldic of refractory epilepsy