Clinical intracranial overview of seizure synchrony and spread.

Ictal semiology most effectively localizes epileptogenesis, but the clinician must be aware of seizure propagation as an influence upon seizure manifestations. This article first reviews basic mechanisms of seizure spread, including alteration of usual routes in some patients whose seizures begin in childhood. In addition to intra-cortical spread, propagation pathways include the commissures, thalamus and brain stem. The second section reviews common clinical phenomena consequent to a few frequently encountered propagation patterns.