Abstracts

Rationale: Purpose: To describe the EEG features and semiology of pediatric epilepsy with photosensitivityMethods: The EEG records of four hundred twenty four patients between the ages of 0 to 18 years of age who had positive photosensitivity while undergoing EEG were identified between January 1996 and July 2006. Clinical history and neuroimaging records were reviewed and correlated with the identified photoparoxysmal EEG patterns. Clinical reports were reviewed to identify clinical epileptic syndromes associated with photosensitivity and its long term outcome. A minimum of one year follow up was required for the study. Results: Four types of photosensitive EEG patterns were identified: photoparoxysmal, photoconvulsive, photomyoclonic, and pattern sensitive. All photosensitive EEG responses identified were associated with generalized seizure types and generalized epileptic syndromes. No particular photosensitivity EEG pattern was identified to be indicative of a specific primary or a symptomatic epileptic syndrome. The presence of photosensitivity did not correlate with clinical outcome. Conclusions: Photosensitive EEG patterns tend to be specific of generalized seizure types and generalized epileptic syndromes. The predominance of generalized epileptic syndromes suggests a probable common genetic component. Cohorts of patients with specific photosensitive EEG patterns can help to delineate the molecular basis of photosensitivity.