SUMMARYPurpose: The identification of the epileptic zone in patients with mesial temporal lobe epilepsy sometimes requires intracranial recordings, for example, with foramen ovale electrodes (FOE). This paper reviews and analyzes the resulting complications in a series of patients studied with bilateral FOE for presurgical evaluation. Prior to performing surgery for refractory mesial temporal lobe epilepsy (MTLE), the epileptogenic zone must be correctly identified (Lüders and Awad, 1991;Engel et al., 1997;Sola, 1997). While noninvasive tests are usually adequate, invasive video-EEG monitoring methods are sometimes required (Boon and Williamson, 1989;Wieser and Williamson, 1993). These can include the use of foramen