Skip to main content Accessibility help

Seizure Types, Epilepsy Syndromes, Etiology, and Diagnosis

  • Jonathan C. Edwards


The clinical manifestation of epileptic seizures may vary widely from patient to patient, depending on the region of the brain involved. Over the centuries, many seizure classific systems have been used, and the current most widely used classification system is that of the International League Against Epilepsy (ILAE). The ILAE system divides seizures into those of partial onset and those of generalized onset, depending on whether the initial clinical manifestations indicate that one cortical region or both hemispheres are involved at the onset of the seizure. Partial seizures are then divided into simple partial seizures, in which a fully conscious state is retained, or complex partial seizures, in which consciousness is impaired. A more recent classification system based purely on symptom features and signs has been proposed, and this system may provide advantages for localization, and especially for surgical evaluation. Epilepsy is a condition characterized by recurrent unprovoked seizures. Epilepsy may be idiopathic, cryptogenic, or symptomatic. Idiopathic epilepsies are generally genetic, and while man such syndromes have been described, advances in molecular genetics will undoubtedly reveal many more syndromes in near future. Cryptogenic epilepsies are those in which an underlying cause is suspected, but the etiology remains undetected. Epilepsies for which there is an underlying structural cause or major metabolic derangement are considered symptomatic. Common causes and diagnostic evaluation are described in this article.


Corresponding author

Please direct correspondence to: Jonathan C. Edwards, MD, University of Michigan Medical Center, Department of Neurology, 1500 E. Medical Center Drive, UH1B300/0036, Ann Arbor, MI 48109; Tel: 734-936-9030; Fax: 734-936-5520; E-mail:


Hide All
1. Bancaud, J, Henriksen, O, Rubio-Donnadieu, F et al. , Proposal for revised clinical and eleotroencephalographic classification of epileptic seizures. Epilepsia. 1981;22:489501.
2. Engel, J JrJr. Editorial commentary:Classification of epileptic disorders [editorial commentary]. Epilepsia. 2001;42:316.
3. Penfield, W, Perot, P. The brain's record of auditory and visual experience: a final summary and discussion. Brain. 1963;86:595696.
4. Lüders, H, Acharya, J, Baumgarter, C et al. , Semiological seizure classification. Epilepsia. 1998;39:10061013.
5. Lüders, HO, Burgess, R, Noachtar, S. Expanding the international classification of seizures to provide localization information. Neurology. 1993;43:16501655.
6. Parra, J, Augustijn, PB, Geerts, Y et al. , Classification of epileptic seizures: a comparison of two systems. Epilepsia. 2001;42:476482.
7. Commission on classification and terminology of the international league against epilepsy. Proposal for revised classification of epilepsies and epileptic syndromes. Epilepsia. 1989;30:389399.
8. Lüders, H, Lesser, RP, Dinner, DS, Morris, HH. Benign focal epilepsy of childhood. In: Lüders, H, Lesser, RP, eds. Electroclinical Syndromes. New York, NY: Springer-Verlag; 1987:303346.
9. Lerman, P, Kivity, S. Benign focal epilepsy of childhood. Arch Neurol. 1975;32:261264.
10. Berkovic, SF, Howell, RA, Hopper, JL. Familial temporal lobe epilepsy: a new syndrome with adolescent/adult onset and a benign course. In: Wolf, P, ed. Epileptic Seizures and Syndromes. London, England: John Libbey; 1994:257263.
11. Berkovic, SF, McIntosh, AM, Howell, RA et al. , Familial temporal lobe epilepsy: a common disorder identified in twins. Ann Neurol. 1996;40:227235.
12. Scheffer, IE, Bhatia, KP, Lopes-Cendes, I et al. , Autosomal dominant frontal epilespy misdiagnosed as sleep disorder. Lancet. 1994;343:515517.
13. Scheffer, IE, Bhatia, KP, Lopes-Cendes, I et al. , Autosomal dominant nocturnal frontal epilepsy: a distinctive clinical disorder. Brain. 1995;118:6173.
14. Semah, F, Picot, M-C, Adam, C et al. , Is the underlying cause of epilepsy a major prognostic factor for recurrence? Neurology. 1998;51:12561262.
15. Stephen, LJ, Kwan, P, Brodie, M. Does the cause of localisation-related epilepsy influence the response to antiepileptic drug treatment? Epilepsia. 2001;42:357362.
16. Boouma, PAD, Westendorp, RGJ, Van Dijk, JG et al. , The outcome of absence epilepsy: a meta-analysis. Neurology. 1996;47:802808.
17. Andermann, F, Berkovic, S. Idiopathic generalized epilepsy with generalized and other seizures in adolescence. Epilepsia. 2001;42:317320.
18. Hauser, WA, Annegers, JF, Kurland, LT. Incidence of epilepsy and unprovoked seizures in Rochester, Minnesota: 1935–1984. Epilepsia. 1994;34:453468.
19. Hauser, WA, Annegers, JF, Kurland, LT. The prevalence of epilepsy in Rochester, Minnesota, 1940–1980. Epilepsia. 1991;32:429445.
20. Wyllie, E, Comair, YG, Kotagal, et al. , Seizure outcome after epilepsy surgery in children and adolescents. Ann Neurol. 1998;44:740748.
21. Edwards, JC, Wyllie, E, Ruggeri, PM et al. , Seizure outcome after surgery for epilepsy due to malformation of cortical development. Neurology. 2000;55:11101114.
22. Bergin, PS, Fish, DR, Shorvon, SD et al. , Magnetic resonance imaging in partial epilepsy: additional abnormalities shown with the fluid-attenuated inversion recovery (FLAIR) pulse sequence. J Neurol Neurosurg Psychiatry. 1955;58:439443.

Related content

Powered by UNSILO

Seizure Types, Epilepsy Syndromes, Etiology, and Diagnosis

  • Jonathan C. Edwards


Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed.