The 2017 ILAE classification of seizures, epilepsies, and epilepsy syndromes aims to group seizures according to clinical presentation and its origin in the brain. and epilepsies according to seizure type, age of onset, probability of remission, EEG findings, radiologic findings, and genetics.
- The 2017 ILAE classification of seizures, epilepsies, and epilepsy syndromes aims to group
- seizures according to
- clinical presentation and its origin in the brain. and
- epilepsies according to
- seizure type, age of onset, probability of remission, EEG findings, radiologic findings, and genetics.
- An emphasis is now placed on etiology.
- The epilepsy syndrome is a new addition to the current classification system and is defined as
- “a cluster of features incorporating seizure types, EEG, and imaging that tend to occur together”.
- Factors that contribute to epilepsy syndrome include
- Age of onset
- Diurnal variation
- Intellectual and psychiatric dysfunction
- EEG findings
- Imaging studies
- Family history and genetics.
- 1981: Difference between partial or generalized seizures.
- 1985: Difference between idiopathic or symptomatic.
- 1989: Added cryptogenic epilepsies and termed them symptomatic.
- 2005: Updated seizure definition is a “transient occurrence of signs and/or symptoms due to abnormal excessive or synchronous neuronal activity in the brain”
- 2014: ILAE redefined epilepsy as a “disease” and not as a“disorder”
- Epilepsy is two unprovoked seizure events.
- Epilepsy is diagnosed if an individual has seizure and his or her “brain demonstrates a pathologic tendency to have one unprovoked or reflex recurrent seizures.”
- After the initial event the probability was considered to be at least 60% within the next 10 years.
Originate from one hemisphere that may be localised or widely distributed.
Originates from more than one region of the brain.
Seizure not under any of the previous classification
These seizures do not fall in a specific category or possible with new genetic and radiology information. Hence ILAE left an option for unclassified epilepsies.
- Tonic - Atonic - Clonic - Myoclonic - Automatisms - Epileptic Spasms - Hyperkinetic
- Tonic - Clonic - Tonic -Clonic - Atonic - Myoclonic - Myoclonic-tonic-clonic - Myoclonic-atonic - Epileptic spasms
- Tonic-clonic - Epileptic spasms
- Autonomic - Cognitive - Behavior Arrest - Emotional - Sensory
- Typical - Atypical - Myoclonic - Eyelid Myoclonia
Focal to bilateral Tonic-Clonic
One or more of the generalised seizures
One or more of the focal seizures
Combined generalised and focal epilepsy
- Unifocal - Multifocal
- Myoclonic Jerks
- Lennox - Gastaut Syndrome - Dravet Syndrome
Focal slowing or epileptiform discharges
Generalised spike-wave activity
EEG findings of both generalised and focal epilepsy
Idiopathic or Genetic Syndrome
Well-described Focal Syndrome
Genetic or self
Seizures are provoked by a specific stimulus
Childhood epilepsy with centrotemporal spikes and panayiotopoulos syndrome.
- Childhood Absence - Juvenile Absence - Juvenile Myoclonic - Generalised Tonic-clonic
- Generalised tonic-clonic - Photosensitive - Reading - Startle
- Focal motor hemifacial - Nocturnal focal motor evolving to bilateral tonic-clonic seizures. - Focal autonomic seizures.
Genetic mutation either inherited or new, family history or syndromes
Meningitis and Encephalitis-Neurocysticercosis, HIV, Cytomegalovirus, and cerebral toxoplasmosis
Secondary to a known metabolic disorder with seizures as one of the main symptom
anti-N-methyl-D-aspartate, anti-leucine-rich, glioma inactivated 1 encephalitis
Stroke, trauma, tumour, malformations of cortical development, and infection
No clear etiology
- Pack AM. Epilepsy Overview and Revised Classification of Seizures and Epilepsies. Continuum (Minneap Minn). 2019 Apr;25(2):306-321. doi: 10.1212/CON.0000000000000707. PMID: 30921011.
- Fisher, Robert S. et al. “Operational Classification of Seizure Types by the International League Against Epilepsy: Position Paper of the ILAE Commission for Classification and Terminology.” Epilepsia 58.4 (2017): 522–530. Web.
- Fisher RS, Cross JH, French JA, Higurashi N, Hirsch E, Jansen FE, Lagae L, Moshé SL, Peltola J, Roulet Perez E, Scheffer IE, Zuberi SM. Operational classification of seizure types by the International League Against Epilepsy: Position Paper of the ILAE Commission for Classification and Terminology. Epilepsia. 2017 Apr;58(4):522-530. doi: 10.1111/epi.13670. Epub 2017 Mar 8. PMID: 28276060.
- Fisher RS, Cross JH, D'Souza C, French JA, Haut SR, Higurashi N, Hirsch E, Jansen FE, Lagae L, Moshé SL, Peltola J, Roulet Perez E, Scheffer IE, Schulze-Bonhage A, Somerville E, Sperling M, Yacubian EM, Zuberi SM. Instruction manual for the ILAE 2017 operational classification of seizure types. Epilepsia. 2017 Apr;58(4):531-542. doi: 10.1111/epi.13671. Epub 2017 Mar 8. PMID: 28276064.
- Scheffer IE, Berkovic S, Capovilla G, Connolly MB, French J, Guilhoto L, Hirsch E, Jain S, Mathern GW, Moshé SL, Nordli DR, Perucca E, Tomson T, Wiebe S, Zhang YH, Zuberi SM. ILAE classification of the epilepsies: Position paper of the ILAE Commission for Classification and Terminology. Epilepsia. 2017 Apr;58(4):512-521. doi: 10.1111/epi.13709. Epub 2017 Mar 8. PMID: 28276062; PMCID: PMC5386840.
- Proposal for revised clinical and electroencephalographic classification of epileptic seizures. From the Commission on Classification and Terminology of the International League Against Epilepsy. Epilepsia. 1981 Aug;22(4):489-501. doi: 10.1111/j.1528-1157.1981.tb06159.x. PMID: 6790275.
- Proposal for classification of epilepsies and epileptic syndromes. Commission on Classification and Terminology of the International League Against Epilepsy. Epilepsia. 1985 May-Jun;26(3):268-78. PMID: 3924589.
- Proposal for revised classification of epilepsies and epileptic syndromes. Commission on Classification and Terminology of the International League Against Epilepsy. Epilepsia. 1989 Jul-Aug;30(4):389-99. doi: 10.1111/j.1528-1157.1989.tb05316.x. PMID: 2502382.
- Berg AT, Berkovic SF, Brodie MJ, Buchhalter J, Cross JH, van Emde Boas W, Engel J, French J, Glauser TA, Mathern GW, Moshé SL, Nordli D, Plouin P, Scheffer IE. Revised terminology and concepts for organization of seizures and epilepsies: report of the ILAE Commission on Classification and Terminology, 2005-2009. Epilepsia. 2010 Apr;51(4):676-85. doi: 10.1111/j.1528-1167.2010.02522.x. Epub 2010 Feb 26. PMID: 20196795.
- Fisher RS, Acevedo C, Arzimanoglou A, Bogacz A, Cross JH, Elger CE, Engel J Jr, Forsgren L, French JA, Glynn M, Hesdorffer DC, Lee BI, Mathern GW, Moshé SL, Perucca E, Scheffer IE, Tomson T, Watanabe M, Wiebe S. ILAE official report: a practical clinical definition of epilepsy. Epilepsia. 2014 Apr;55(4):475-82. doi: 10.1111/epi.12550. Epub 2014 Apr 14. PMID: 24730690.
- Thomas RH, Berkovic SF. The hidden genetics of epilepsy-a clinically important new paradigm. Nat Rev Neurol. 2014 May;10(5):283-92. doi: 10.1038/nrneurol.2014.62. Epub 2014 Apr 15. PMID: 24733163.