Clinical and EEG Analysis of Patients With Idiopathic Generalized Epilepsy and Photosensitivity

Introduction: Our aim is to define the electroclinical characteristics of patients with photosensitive idiopathic generalized epilepsy (IGE) and to investigate the differences in seizure types, therapy and outcome between subgroups, based on photoparoxysmal response (PPR)/EEG characteristics and different syndromes.Patients and Methods: Fifty consecutive patients with a diagnosis of IGE and having EEG or clinical evidence for photosensitivity have been identified from the epilepsy outpatient clinic database of the Department of Neurology (Istanbul Medical Faculty, Istanbul University). Clinical and EEG data was collected retrospectively.Results: Thirty-six female and 14 male patients with median age 25.5 (14-63) were included to the study. The juvenile myoclonic epilepsy (JME) subgroup (n:24) had a significantly higher current age (p=0.035) and age at onset of seizures (p=0.029) compared with the absence epilepsy (AE) (n:12). Sleep deprivation triggers the seizures significantly more often in the JME subgroup compared with AE (p=0.003). Seizure records during EEG significantly more often in patients with AE (p=0.016). Patients with prolonged PPRs experienced significantly more clinical seizures during an EEG recording than patients with self-limited PPRs (p=0.000). The patients who were not seizure free had significantly more absence seizures (AS) (initially) compared with the patients who became seizure free (p=0.001).Conclusion: Our findings in a retrospective cohort suggest that having AS is a negative prognostic factor for the seizure outcome in patients with photosensitive IGE.