Clinical Neurophysiology Detroit Medical Center Detroit, Michigan
Rationale: Generalized interictal and ictal features in adult patients with focal epilepsy are poorly characterized. The aim of the present study is to assess electrographic (EEG) characteristics of patients with focal epilepsy and generalized epileptiform discharges, their frequency and impact on clinical features. Methods: We retrospectively reviewed consecutive patients with focal epilepsy admitted to the Epilepsy Monitoring Unit for diagnostic and assessment over the past 12 months. Video-EEG monitoring was performed using 21 scalp electrodes according to the International10/20 system. In some patients, additional sphenoidal electrodes were inserted. Diagnosis of focal epilepsy is based on seizure semiology, interictal and ictal EEG recordings as well as neuroimaging. Focal seizures with or without secondary generalization were analyzed. Inclusion criteria include a minimum of one focal seizure with or without secondary generalization during the monitoring. If the patient had several seizures, only the first three seizures were included in the study. Generalized epileptiform discharges (GED) and generalized seizures were investigated. All clinical and laboratory findings of both groups were compared using parametric statistical analysis.
Results: A total of 35 patients were included. GED were present in seven (21; 3 males) patients; six out of seven also had generalized seizures. Two patients (6%) had focal and generalized seizures in the same admission. Of 85 seizures captured, 16 (19%) had generalized ictal onset. The most common epilepsies with GED were fronto-temporal epilepsies. Five out of six patients with GED also had focal discharges; one patient only had GED. We did not find any association among gender and seizures duration and the presence of generalized seizures.
Conclusions: The presence of generalized seizures and epileptiform discharges is not uncommon in adults with focal epilepsy. Focal and generalized seizures can coexist, and generalized features are most commonly seen in patient with fronto-temporal epilepsy. Funding: Please list any funding that was received in support of this abstract.: None