Association of Lateralized Interictal Epileptiform Discharges with Postsurgical Seizure Outcomes in Patients with Tuberous Sclerosis Complex: A 10-Year Retrospective Study at a Single Center

Objective. Tuberous sclerosis complex (TSC) is a rare neurodevelopmental disorder often associated with intractable epilepsy, and surgical resection is the effective therapeutic approach to alleviate seizures in TSC patients. Scalp electroencephalogram (EEG) is a noninvasive method used to diagnose epilepsy; however, the relationship between scalp video-EEG findings and postsurgical seizure outcomes has not been fully evaluated in TSC patients. Materials and Methods. The relationship between clinical characteristics and seizure outcomes of TSC patients with 1-year, 5-year, and 10-year follow-ups was retrospectively analyzed. We explored the association of interictal epileptiform discharges (IEDs) with postsurgical seizure outcomes. Further, the differences in clinical characteristics among four IED patterns (focal, lateralized, multifocal, and generalized IEDs) were assessed. Results. A total of 82 patients were enrolled in this study. There were 82 patients with 1-year follow-up, 75 patients with 5-year follow-up, and 57 patients with 10-year follow-up, and the IEDs were associated with the postsurgical outcomes. Patients with focal, lateralized, and generalized IEDs had seizure freedom (SF) in 1-year follow-up, respectively. Intriguingly, patients with lateralized IEDs had long-term SF in 5-year and 10-year follow-ups. Conclusions. A significant association existed between IEDs and long-term postsurgical outcomes in TSC patients. TSC patients with lateralized IEDs often showed long-term SF and mild clinical epileptic characteristics. According to our study, IEDs may guide clinical care for TSC patients with intractable epilepsy.