Patients presenting with transient neurological symptoms in the context of subdural hemorrhage may present a diagnostic challenge. Many of these patients end up with a probable diagnosis of epilepsy (or acute symptomatic seizures), despite a negative electroencephalogram. The investigators believe that the origin of these transient neurologic symptoms in a significant subpopulation of these patients may in fact be cortical depolarization, rather than epileptiform activity. Very specific characteristics have already been identified that differentiate these patients from those who ultimately have epilepsy. The NESIS entity (nonepileptic, stereotypical, and intermittent symptoms) has been proposed to represent this group of patients. A NESIS score was then designed to help distinguish patients with epileptiform activity (confirmed by EEG) from those likely to have cortical depolarization. In other diseases presenting cortical depolarizations, certain antiepileptic treatments (including Topiramate) have already been recognized as effective. The investigators therefore want to perform a prospective, multicenter, randomized-controlled study (Topiramate group and Levetiracetam group) to determine whether a significant difference in the response to treatment exists between Topiramate and Levetiracetam in the NESIS group compared to the non-NESIS group. In addition, in a few eligible patients, the investigators will implant an electrocorticography electrode to demonstrate the existence of cortical depolarizations.
