Commentary: ILAE Definition of Epilepsy

Abstract

The report by Fisher and colleagues is an excellent first step to provide operational definitions of epilepsy but there is considerably more to be accomplished. In the past absence of data expert opinion had a place in establishing definitions. When data is available, evidence based systematic review seems more appropriate14. Definition 1 is evidence based. For epilepsy definition 2, systematic reviews could be undertaken to provide definitive risk estimates to define epilepsy in association with putative clinical scenarios using as a baseline risk for further seizures in those with two unprovoked seizures and identify areas where further work is necessary. To define resolved epilepsy,a level of risk should be set (for example 1% per year) rather than using an arbitrary time of seizure freedom. A systematic assessment of data could then be undertaken to determine when this risk is attained. In successful surgical cases for example, the point at which seizure recurrence risk reaches 1% may be less than a 10 years of seizure freedom. It remains to be seen how the proposed definitions will influence the clinical course of epilepsy. Let's hope that these modified definitions lead to both improved patient function and outcomes and act as a stimulus to further clinical research.