Insights in classification of seizures and epilepsies – review of key concepts throughout history

Abstract

Since the Babylonian era up to nowadays, the large complexity of epileptic disorders made the attempt of classifying and organizing concepts one of the most challenging. The 1981 classification was a revision of the one devised by Henri Gastaut for the ILAE and published in 1970. The distinction between simple and complex partial seizures represented a significant difference. In 1989 the report of ILAE classification and terminology task force introduced the concept of epileptic syndrome. An epileptic syndrome is defined by the sum of signs and symptoms that tend to occur together, not reflecting a particular etiology and prognosis, these latter features being the hallmark not of a syndrome, but of a disease condition. Firstly, any epileptic disorder can be described as either idiopathic (primary, whose etiology is probably genetic), symptomatic (with a known or presumed cerebral pathology) or cryptogenic (with an occult cause). The epileptic diagnostic tree ramifies into four main branches in the 1989 ILAE Classification: localization-related (focal, local, or partial) epilepsies and syndromes, generalized epilepsies and syndromes, epilepsies and syndromes undetermined whether focal or generalized and special syndromes. The next important milestone in epilepsy classification was settled by ILAE in 2001, when a glossary for ictal semiology was developed and multiaxial approach of diagnosing epilepsy was proposed. The necessity of processing the new insights in epilepsy was answered by the latest ILAE Report released in february 2010, which brings awareness of and appropriately integrates the currently available data. It presents a modular approach of diagnosing epilepsy and recommends to keep a flexible vision on this topic, as every individual case requires a different prioritizing scheme.

Keywords

• seizure
• epileptic syndrome
• epilepsy
• classifi cation