Age dependent consequences of seizures: Relationship to seizure frequency,brain damage, and circuitry reorganization

Seizures in the developing brain pose a challenge to the clinician. In addi tion to the acute effects of the seizure, there are questions regarding the impact of severe or recurrent seizures on the developing brain. Whether pr ovoked seizures cause brain damage, synaptic reorganization, or epilepsy is of paramount importance to patients and physicians. Such questions are esp ecially relevant in the decision to treat or not treat febrile seizures, a common occurrence in childhood. These clinical questions have been addresse d using clinical and animal research. The largest prospective studies do no t find a causal connection between febrile seizures and later temporal robe epilepsy. The immature brain seems relatively resistant to the seizure-ind uced neuronal loss and new synapse formation seen in the mature brain. Labo ratory investigations using a developmental rat model corresponding to huma n febrile seizures find that even though structural changes do not result f rom hyperthermic seizures, synaptic function may be chronically altered. Th e increased under standing of the cellular and synaptic mechanisms of seizu re-induced damage may benefit patients and clinicians in the form of improv ed therapies to attenuate damage and changes induced by seizures and to pre vent the development of epilepsy. (C) 2000 Wiley-Liss, Inc.