[Epileptic auras: classification, pathophysiology, practical usefulness, differential diagnosis and controversials].

OBJECTIVE

To examine those aspects of the epileptic auras that may contribute to improve our understanding of this epileptic manifestation.

DEVELOPMENT

Epileptic aura is that portion of the seizure which occurs before consciousness is loss and for which memory is retained afterwards. In the case of simple partial seizures, the aura is the entire seizure. This epileptic phenomenon is the consequence of the activation of functional cortex by abnormal, unilateral, circumscribed and brief neuronal discharge. Surface electroencephalogram frequently fails to detect any changes during an isolated aura. The incidence of auras in partial epilepsy remains imprecise and there are marked discrepancies among authors. Viscerosensorial and experiential auras are most often seen in temporal lobe epilepsy. Feeling of fear is the commonest affective symptom associated with epileptic discharges from mesial temporal origin. Special sensory auras including visual, gustatory and vertiginous are more frequently described in extratemporal epilepsy. Olfactory auras are rare, however, when they occur the most likely etiology is a tumor involving the amygdala and hippocampus. Somatosensory auras include sensations of tingling or numbness, electrical feeling or very occasionally, pain. There is not agreement with the classification of determined auras such as motor, cephalic and sexual. The differential diagnosis is enormously heterogeneous including vestibular disfunction, migraine, stroke, autonomic disturbances, drug intoxications and psychiatric disorders.

CONCLUSION

The clinical manifestations of the epileptic auras are extraordinarily diverses and, therefore, the knowledge of their pathophysiology, characteristics, incidence and association with differents types of focal epilepsy are the clue to obtain a precise diagnosis.