Abstracts

Rationale: In most cases, the differentiation of frontal seizures from non-epileptic or temporal seizures is based on a thorough history, which can be at times insufficient or misleading. Interictal EEG is used to support the diagnosis of epilepsy and aid in its differential diagnosis. However, it is less sensitive and specific in frontal seizures. Objectives: To evaluate the yield of long-term video-EEG in patients with frontal seizures. Methods: We retrospectively reviewed the EEG recordings and medical records of 35 patients with frontal seizures recorded during noninvasive long-term video-EEG monitoring in Tel Aviv Sourasky Medical Center between 2003 and 2008. Results: The study group included 18 (51%) women and 17 (49%) men, aged 15 to 82 years (mean- 27±13). Epilepsy duration ranged between 0.5 to 45 years (mean-16±9). One to 50 seizures (mean- 16±16) were recorded during 4 to 29 days (mean- 13±6) of monitoring. A lesion was detected on MRI in 18 (51%) patients, confined to the frontal lobe in 11 (61%). Interictal epileptiform discharges (IEDs) and ictal EEG were recorded in 17 (49%) and 32 (91%) patients, respectively, and were localized to the frontal lobe in 10 (29%) and 19 (54%) patients, respectively. Neither localized interical nor ictal discharges were associated with a lesional MRI (p=0.283, p=1.0, respectively). Conclusions: The diagnostic yield of noninvasive long-term video-EEG in patients with frontal seizures is higher for ictal EEG compared to IEDs, and is not associated with a lesional MRI.