Auras, seizure focus, and psychiatric disorders.

Abstract

Objective: The goal of this study was to assess the types of auras and their associations with the focus of seizures in 144 consecutive adult patients with partial epilepsy refractory to medical treatment. The association of frequency and type of aura with a psychiatric disorder was also studied.

Background: The nature of the aura, its association with the seizure focus, and its relation with emotions and behavioral dysfunction have received relatively little attention, and remain controversial.

Methods: Patients were admitted to an epilepsy investigation unit for detailed observation of their seizures and type of aura. Patients underwent standard electroencephalographic telemetry, including implanted subdural electrodes, if necessary, to delineate the seizure focus. The auras were classified into nine categories. All patients had an independent clinical psychiatric interview for a Diagnostic and Statistical Manual, Third Edition-Revised (DSM-III-R)-based diagnosis.

Results: Of the 144 patients studied, 111 (77.1%) had one or more symptoms during the aura and 33 (22.9%) had no aura. The most frequent aura types were viscerosensory (47 cases [32.6%]), experiential (44 cases [30.6%]), and cephalic (21 cases [14.6%]). A temporal lobe focus was present in 116 (80.5%) patients. Only experiential auras were significantly associated with a temporal lobe seizure focus (33 of 44 cases). A DSM-III-R psychiatric diagnosis was present in 74 (51.4%) patients. Of the 116 patients with a temporal lobe focus, 60 (50.2%) had a DSM-III-R psychiatric diagnosis. Patients with two or more auras were significantly more likely to have a psychiatric diagnosis (70.2%) compared with those with one aura (39.1%) or no aura (48.5%). A significant association between experiential auras and psychiatric morbidity was seen.

Conclusions: Auras occurred in a majority of patients with a treatment-refractory partial epilepsy who were hospitalized for assessment of their seizure focus for possible surgical candidacy. Two or more auras were associated with a psychiatric diagnosis as was the presence of an experiential aura. Experiential auras were most common in temporal lobe epilepsy. Approximately half the patients, irrespective of seizure focus, had an associated psychiatric morbidity.