Epilepsy is a common neurological disorder that has a varied presentation and requires two or more unprovoked seizures at least 24 hours apart for diagnosis. MRI is the modality of choice for epilepsy, most often investigating for an underlying cause, especially in adults.
Epilepsy is very common, with ~3% of the population affected at some point in their life 1,5.
Epilepsy syndromes can be generally divided into two broad categories 1,5:
- generalised, e.g. absence epilepsy, tonic-clonic, myoclonic
- partial (localisation-related), can progress to generalised
- temporal lobe epilepsy
- extratemporal epilepsy
There is a wide range of causes, however, in adults with new onset of seizures ~50% will not have a determinable cause 1-5. The International League Against Epilepsy (ILAT) have proposed the following classification 6:
- idiopathic: epilepsy due to an underlying single gene condition or complex inheritance (seizures as the only manifestation)
- cryptogenic: unknown cause
- provoked epilepsy: e.g. secondary to fevers, head trauma, drug-induced
- predominantly genetic/developmental causation
- predominantly acquired
MRI is the modality of choice. Please see articles on specific conditions listed above for imaging features. There are a number of MRI protocols that can be used to investigate patients with seizures.
- 1. Bronen RA. Epilepsy: the role of MR imaging. AJR Am J Roentgenol. 1992;159 (6): 1165-74. doi:10.2214/ajr.159.6.1442376 - Pubmed citation
- 2. Cook M, Lhatoo S. Oxford Textbook of Epilepsy and Epileptic Seizures (Oxford Textbooks in Clinical Neurology). OUP Oxford. ISBN:B009ZAGIDO. Read it at Google Books - Find it at Amazon
- 3. Bronen RA. Epilepsy: the role of MR imaging. AJR Am J Roentgenol. 1992;159 (6): 1165-74. doi:10.2214/ajr.159.6.1442376 - Pubmed citation
- 4. Friedman E. Epilepsy imaging in adults: getting it right. AJR Am J Roentgenol. 2014;203 (5): 1093-103. doi:10.2214/AJR.13.12035 - Pubmed citation
- 5. Chang BS, Lowenstein DH. Epilepsy. N. Engl. J. Med. 2003;349 (13): 1257-66. doi:10.1056/NEJMra022308 - Pubmed citation
- 6. Shorvon SD. The etiologic classification of epilepsy. Epilepsia. 2011;52 (6): 1052-7. doi:10.1111/j.1528-1167.2011.03041.x - Pubmed citation