The value of intraoperative electrocorticography in surgical decision making for temporal lobe epilepsy with normal MRI.

Purpose: We hypothesized that acute intraoperative electrocorticography (ECoG) might identify a subset of patients with magnetic resonance imaging (MRI)-negative temporal lobe epilepsy (TLE) who could proceed directly to standard anteromesial resection (SAMR), obviating the need for chronic electrode implantation to guide resection.

Methods: Patients with TLE and a normal MRI who underwent acute ECoG prior to chronic electrode recording of ictal onsets were evaluated. Intraoperative interictal spikes were classified as mesial (M), lateral (L), or mesial/lateral (ML).

Bilateral intracranial electrodes for lateralizing intractable epilepsy: efficacy, risk, and outcome.

Objective: Medically refractory epilepsy is amenable to neurosurgical intervention if the epileptogenic focus is accurately localized. If the scalp video-electroencephalography (EEG) and magnetic resonance imaging are nonlateralizing, yet a single focus is suspected, video-EEG monitoring with bilateral intracranial electrode placement is helpful to lateralize the ictal onset zone. We describe the indications, risks, and utility of such bilateral surveys at our institution.

Latency to first spike in the EEG of epilepsy patients.

Background: Routine EEGs in individuals with epilepsy have interictal spikes in 56% of cases. The availability of prolonged EEG has changed the use of EEG in the assessment of epilepsy.

Objective: To determine the time to first epileptiform activity on EEG in patients with epilepsy.