Recurrent secondary generalization in frontal lobe epilepsy: Predictors and a potential link to surgical outcome?

Summary Objective Frontal lobe epilepsy ( FLE ) frequently leads to secondary generalized tonic–clonic seizures ( SGTCS ). However, little is known about the clinical, electrophysiologic, and radiologic correlates of SGTCS and whether these could influence diagnosis and treatment. Methods A cohort of 48 patients with confirmed FLE was retrospectively identified and dichotomized into a group with and a group without SGTCS defined by history (≥1/year) or video–electroencephalography ( vEEG ). Demographics, seizure semiology, vEEG , neuroimaging data, and estimated seizure‐onset zone were tabulated, and their association with the occurrence of SGTCS was evaluated with use of a chi‐square test. Independent predictors of SGTCS were confirmed using a stepwise multivariate analysis. Similarly, these predictors as well as a history of SGTCS were tested as multivariate predictors of the postoperative International League Against Epilepsy ( ILAE ) score in the surgical subgroup (n = 25). Results We identified three independent predictors of a history of SGTCS in FLE , including loss of responsiveness at seizure onset (corrected p = 0.04), a semiology involving early elementary motor signs (corrected p = 0.01), and multifocal spikes on EEG (corrected p = 0.02). A seizure‐free outcome occurred in 57% of surgical cases and was more likely in the group without SGTCS (100%, p = 0.001). When considering only SGTCS occurring during video‐ EEG monitoring, the association with semiology and surgical outcome vanished, but the association with preserved awareness and a multifocal EEG persisted. Significance A history of SGTCS is related to a specific ictal semiology and interictal EEG , and may have a role in surgical risk stratification.