Absence seizures: generalized spike-and-wave discharges initiated from a cortical focus

作者：Polack Pierre Olivier^*; Charpier Stephane

来源：Epilepsies, 2010, 22(1): 33-41.

DOI：10.1684/epi.2010.0287

• absence epilepsy
• cerebral cortex
• thalamus
• animal model
• GAERS
• cortical focus

Absence seizures: generalized spike-and-wave discharges initiated from a cortical focus Epileptic seizures are classified by the International League Against Epilepsy into two main groups: partial seizures, initiated from an epileptogenic zone, and generalized seizures. Absence seizures are part of generalized seizures, with spike-and-wave discharges (SWDs) occurring within the thalamo-cortical loop. The origin, cortical or thalamic, of electrical paroxysms associated with absence seizures has been subject of fervent controversies. Consistent with recent electro-clinic findings obtained in human patients, indicating that absences are initiated from discrete cortical zones, studies carried out on WAG/Rij rats and GAERS (Genetic Absence Epilepsy Rat from Strasbourg), two genetic models exhibiting a strong homology with the human pathology, revealed the existence of a cortical focus triggering the SWDs. We specified the mechanisms of seizure initiation by identifying in the GAERS a subpopulation of cortical neurons, hyperactive and showing early ictogenic discharges, from which the SWDs emerge and are secondarily propagated within the cortico-thalamic loop. Altogether, these experimental and clinical findings strongly support the existence of a cortical focus initiating absence seizures, leading to a re-evaluation of the "classical" electro-clinic and etiologic classification of absence epilepsy.

• 出版日期2010-3