Epileptogenesis and Cortical Dysplasias
Cortical dysplasia (CD) is a malformation of brain development characterized by aberrant lamination of the cerebral cortex, pyramidal cell misorientation, and in severe cases, the presence of dysplastic cytomegalic neurons and balloon cells (Taylor et al. 1971). In children undergoing epilepsy neurosurgery, CD is the most frequently identified etiology accounting for over 40% of cases (Harvey et al. 2008). In fact, CD is found in approximately 70% of epilepsy surgery patients operated in the first 2 years of life.
In a widely accepted classification, CD has been divided, based on histopathological criteria, into two main types; mild Type I CD, in which cortical dyslamination is the main feature, and severe Type II CD where, in addition to altered cortical architecture, dysplastic cells are observed (Mischel et al. 1995; Palmini et al. 2004). Dysplastic cells have been hypothesized as potential generators of epileptic discharges (Kerfoot et al. 1999;...
KeywordsPyramidal Neuron Tuberous Sclerosis Complex Cortical Dysplasia Epileptic Activity Epileptic Discharge
List of Abbreviations
Tuberous sclerosis complex
University of California Los Angeles
The authors would like to thank the young patients and their parents for allowing use of resected tissue samples for research purposes. We also thank Raymond S. Hurst, Jorge Flores-Hernández, Elizabeth Hernández-Echeagaray, Nanping Wu, Irene Yamazaki, and Marea K. Boylan, for their assistance in electrophysiological data collection and morphological analyses. The expertise and dedication of the UCLA Hospital Pediatric Neurology Staff are also greatly appreciated. This work was supported by NIH grant NS 38992 from the NINDS.
- Cepeda C, Hurst RS, Flores-Hernandez J, Hernandez-Echeagaray E, Klapstein GJ, Boylan MK, Calvert CR, Jocoy EL, Nguyen OK, Andre VM, Vinters HV, Ariano MA, Levine MS, Mathern GW (2003) Morphological and electrophysiological characterization of abnormal cell types in pediatric cortical dysplasia. J Neurosci Res 72:472–486CrossRefPubMedGoogle Scholar
- Cepeda C, Andre V, Flores-Hernandez J, Nguyen OK, Wu N, Klapstein GJ, Nguyen ST, Koh S, Vinters HV, Levine M, Mathern GW (2005) Correlations between neuroimaging, electrophysiology and location of cytomegalic neurons and balloon cells, and glutamate/GABA synaptic circuits. Dev Neurosci 27:59–76CrossRefPubMedGoogle Scholar
- Lerner JT, Salamon N, Hauptman JS, Velasco TR, Hemb M, Wu JY, Sankar R, Donald Shields W, Engel J Jr, Fried I, Cepeda C, Andre VM, Levine MS, Miyata H, Yong WH, Vinters HV, Mathern GW (2009) Assessment and surgical outcomes for mild type I and severe type II cortical dysplasia: a critical review and the UCLA experience. Epilepsia 50(6):1310–1335CrossRefPubMedGoogle Scholar