The New Classification of Seizures by the International League Against Epilepsy 2017
Purpose of Review
This review presents the newly developed International League Against Epilepsy (ILAE) 2017 classification of seizure types.
The fundamental distinction is between seizures that begin focally in one hemisphere of the brain, generalized onset seizures that apparently originate in both hemispheres, and seizures of unknown onset. Focal seizures optionally can be subclassified according to whether awareness (a surrogate marker for consciousness) is intact or impaired. The next level of classification for focal seizures is motor (with subgroups automatisms, atonic, clonic, epileptic spasms, hyperkinetic, myoclonic, tonic), non-motor (with subgroups autonomic, behavior arrest, cognitive, emotional, sensory), and focal to bilateral tonic-clonic. Generalized seizures are categorized as motor (tonic-clonic, clonic, tonic, myoclonic, myoclonic-tonic-clonic, myoclonic-atonic, atonic, epileptic spasms) and non-motor/absence (typical, atypical, myoclonic, eyelid myoclonia).
The classification allows new types of focal seizures and a few new generalized seizures, and clarifies terms used to name seizures.
KeywordsEpilepsy Seizure Classification Focal seizure Generalized seizure Taxonomy
The International League Against Epilepsy supported travel and incidental expenses involved in task force meetings to develop the classification. Task force members were not paid. The current author is grateful to the Classification Task Force members for their primary input into the material of the Epilepsia papers from which this review is adapted. These members are Helen Cross, Carol D’Souza, Jacqueline A. French, Sheryl Haut, Norimichi Higurashi, Edouard Hirsch, Floor E. Jansen, Lieven Lagae, Solomon L. Moshé, Jukka Peltola, Eliane Roulet Perez, Ingrid E. Scheffer, Andreas Schulze-Bonhage, Ernest Somerville, Michael Sperling, Elza Marcia Yacubian, and Sameer M. Zuberi.
Compliance with Ethical Standards
Conflict of Interest
Robert S. Fisher is supported by the James and Carrie Anderson Research Fund, the Maslah Saul MD Chair, the Susan Horngen Fund, and the Steve Chen Fund. He holds stock options in Avails Medical, Smart Monitor, Zeto, and Cerebral Therapeutics.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance
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