MALFORMATIONS OF CORTICAL DEVELOPMENT AS A CAUSE OF ADULT-ONSET EPILEPSY
Abstract number :
2.072
Submission category :
Year :
2002
Submission ID :
1331
Source :
www.aesnet.org
Presentation date :
12/7/2002 12:00:00 AM
Published date :
Dec 1, 2002, 06:00 AM
Authors :
Erasmo A. Passaro, Diana Gomez-Hassan, Daniela N. Minecan, Ahmad Beydoun. Neurology, Bayfront Medical Center Comprehensive Epilepsy Program, St Petersburg, FL; Neuroradiology, University of Michigan, Ann Arbor, MI; Neurology, University of Michigan, Ann A
RATIONALE: Malformations of cortical development (MCDs) are recognized as a relatively common cause of epilepsy. Approximately 20% of adults and 50% of children treated with epilepsy surgery have MCDs as their pathologic substrate. MCDs are usually associated with childhood or adolescent-onset epilepsy; it has been infrequently described with adult-onset epilepsy. A recent report showed heterotopias as a cause of adult onset epilepsy. We describe patients with adult-onset epilepsy associated with a variety of MCDs
METHODS: In the University of Michigan Epilepsy Clinic, we identified 17 patients with adult onset epilepsy defined as epilepsy onset after age 20.
For all patients the following clinical information was collected: age of onset, seizure type, localization, MRI classification of the MCD and seizure outcome with medical therapy. MRI were reviewed by DGH and EAP and classified according to the classification system of Barkovich and Kuzniecky (2001).
RESULTS: Seventeen patients (six female/11male) were identified with adult- onset epilepsy associated with an MCD. The mean age of onset of epilepsy was 29 years (range 23-37 years). The MCD location was diffuse (3); frontal (3); temporal (7);occipital (3) and parietal (1). Two of the patients with temporal MCDs had mesial dysplasia and 5 had cortical dysplasia. All patients had partial onset seizures with infrequent secondarily generalized tonic-clonic seizures. The following MCDs were identified on MRI: mesial dysplasia (2); cortical dysplasia (10); polymicrogyria (2) and heterotopia (3). Nine of seventeen patients were not controlled with anti-epileptic drugs.
CONCLUSIONS: MCDs can be a cause of adult-onset partial epilepsy. A wide range of MCDs cause epilepsy in adults with cortical dyslasia as the most common type. High resolution MRI with epilepsy protocol and multi-planar reformatting is necessary to identify these MCDs. Temoral lobe location is most common, and in some patients the MCD can be diffuse (i.e. PMG and heterotopias), and in most it is focal (i.e. cortical dysplasia).
Identification of these MCDs is important in that it could have implications for long term prognosis for seizure control. Future studies are necessary to understand why the epileptogenicity of MCDs is expressed in childhood and adolescence in most patients and in adulthood in others.
[Supported by: Paul Cumbo Fund]