Is epilepsy a progressive disease? The neurobiological consequences of epilepsy

While primary, or idiopathic, epilepsies may exist, in the vast majority of cases epilepsy is a symptom of an underlying brain disease or injury. In t hese cases, it is difficult if not impossible to dissociate the consequence s of epilepsy from the consequences of the underlying disease, the treatmen t of either the disease or the epilepsy, or the actual seizures themselves. Several cases of apparent complications of epilepsy are presented to illus trate the range of consequences encountered in clinical practice and the di fficulty in assigning blame for progressive symptomatology in individual ca ses. Because of the difficulty in interpreting clinical material, many inve stigators have turned to epilepsy models in order to address the potential progressive consequences of recurrent seizures. The authors review experime ntal data, mainly from animal models, that illustrate short-, medium-, and long-term morphological and biochemical changes in the brain occurring afte r seizures, and attempt to relate these observations to the human condition .