Abstracts

Rationale: The timing providing highest yield of initial EEG after new onset unprovoked seizures both in diagnosis and patient care is an important and practical issue. Current guidelines suggest routine EEGs are standard of care in work-up of new onset unprovoked seizures. However, yield of the initial EEG and exact timeframe in which to perform remain unclear. AAN 2007 practice parameter article quotes 48 hours to an average of 15 days, also suggests, in children, if done within 24 hours, is higher yield of abnormalities.(“Practice Parameter: Evaluating an Apparent unprovoked first seizure in adults (an evidence-based review)”. AAN Neurology (2007); 69: 1996-2007.) Standardization for both adult and pediatric groups however is still lacking. Objective: To determine concrete timeframe to perform initial EEG in new onset unprovoked seizures and provide a greater yield of EEG benefits in managing these patients.Methods: Retrospective chart review study of both pediatric and adult patients identified from EEG Database over January 1999-December 2014 located at Womens and Childrens Hospital of Buffalo using keyword “new onset seizure”. Inclusion criteria: unprovoked; age >=1 year; new onset. Exclusion criteria: provoked; age <1; h/o stroke; known seizure history; status epilepticus, benign Rolandic epilepsy; abnormal CT/MRI brain. EEG reports evaluated to determine presence or absence of epileptiform discharges. Demographic data including age, gender, time (hours) from seizure onset to obtaining EEG and presence of epileptiform discharges collected. Chi-square and logistic regression model used for data analysis. Significance set at p<0.05. SPSS used for statistical analysis.Results: Total of 59,181 records in EEG database. 899 identified and 270 met inclusion criteria. For the EEG’s performed in the first 6 hours, 67% revealed presence of epileptiform discharges. For 6-12 hours, 52% had epileptiform discharges; 12-24 hours 24% demonstrated presence. For 24-48 hours, 25% presence; 48-72 hours revealed 22% presence; 72-96 hours, 18% presence and >