Brain Advance Access published online on November 29, 2005
Brain, doi:10.1093/brain/awh687
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
1 Epilepsy Center, University of Freiburg, Freiburg, Germany
* To whom correspondence should be addressed. Hippocampal sclerosis is often associated with macroscopic or microscopic dysplasia in the temporal neocortex (TN). The relevance of such a dual pathology with regard to epileptogenesis is unclear. This study investigates the role of both pathologies in the generation of ictal and interictal activity. Ictal (113 seizures) and interictal data from invasive EEG recordings with simultaneous depth electrodes in the hippocampus and subdural electrodes over the TN were analysed retrospectively in 12 patients with variable degrees of hippocampal sclerosis and different types of histologically confirmed temporal cortical dysplasia [all male, age at epilepsy onset <1-29 years (mean 9.6 years), age when invasive recordings were performed 6-50 years (mean 28.2 years)]. Of the seizures 41.3% arose from the amygdala/hippocampus complex (AHC), 34.7% from the TN, 22% were simultaneously recorded from AHC and TN (indeterminate seizure onset), and 2% from other regions. In three patients, seizure onset was recorded only from the AHC. In patients with severe hippocampal sclerosis only 12% of the seizures arose from the TN, whereas in patients with mild hippocampal sclerosis 58% arose from the TN. The type of cortical dysplasia, however, did not predict seizure onset in the AHC or TN. Propagation time from the TN to the AHC tended to be shorter (mean 7.4 s) than vice versa (mean 13.7 s). The most common initial ictal patterns in the AHC were rhythmic beta activity (<25 Hz) and repetitive sharp waves, and in the TN were fast activity (>25 Hz) and repetitive sharp waves. The interictal patterns over the TN were similar to those seen over extratemporal focal cortical dysplasias. Simultaneous recordings from the hippocampus and the TN strongly suggest that dysplastic tissue in the TN is often epileptogenic. The quantitative contribution of the hippocampus to seizure generation corresponded with the degree of hippocampal pathology, whereas different subtypes of cortical dysplasia did not affect its relative contribution to seizure generation and even mild forms of dysplasia were epileptogenic.
Received April 18, 2005
Revised July 11, 2005
Accepted October 7, 2005
Article
Epileptogenicity of cortical dysplasia in temporal lobe dual pathology: an electrophysiological study with invasive recordings
Susanne Fauser 1 *
and
Andreas Schulze-Bonhage 1
Susanne Fauser, E-mail: fauser{at}nz11.ukl.uni-freiburg.de
Abstract 
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  S. Fauser, S. M. Sisodiya, L. Martinian, M. Thom, C. Gumbinger, H.-J. Huppertz, C. Hader, K. Strobl, B. J. Steinhoff, M. Prinz, et al. Multi-focal occurrence of cortical dysplasia in epilepsy patients Brain, August 1, 2009; 132(8): 2079 - 2090. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. J. Hamberger, W. T. Seidel, R. R. Goodman, A. Williams, K. Perrine, O. Devinsky, and G. M. McKhann II Evidence for cortical reorganization of language in patients with hippocampal sclerosis Brain, November 1, 2007; 130(11): 2942 - 2950. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Fauser, H.-J. Huppertz, T. Bast, K. Strobl, G. Pantazis, D.-M. Altenmueller, B. Feil, S. Rona, C. Kurth, D. Rating, et al. Clinical characteristics in focal cortical dysplasia: a retrospective evaluation in a series of 120 patients Brain, July 1, 2006; 129(7): 1907 - 1916. [Abstract] [Full Text] [PDF]
|
|