Address correspondence and reprint requests to Dr. I. M. Najm at Section of Epilepsy, 9500 Euclid Avenue, S51, Cleveland, OH 44195, U.S.A. E-mail: [email protected]

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Abstract

Summary: Purpose: Malformations due to abnormal cortical development (MCDs) are common pathologic substrates of medically intractable epilepsy. The in situ epileptogenicity of these lesions as well as its relation to histopathologic changes remains unknown. The purpose of this study was to correlate the cellular patterns of MCDs with the expression of focal cortical epileptogenicity as assessed by direct extraoperative electrocorticographic (ECoG) recordings by using subdural grids.

Methods: Fifteen patients with drug-resistant focal epilepsy due to pathologically confirmed MCD who underwent subdural electrode placement for extraoperative seizure localization and cortical mapping between 1997 and 2000 were included in the study. Areas of interictal spiking and ictal-onset patterns were identified and separated during surgery for further pathologic characterization (cellular and architectural). Three pathologic groups were identified: type I; architectural disorganization with/without giant neurons, type IIA; architectural disorganization with dysmorphic neurons, and type IIB; architectural disorganization, dysmorphic neurons, and balloon cells (BCs). The focal histopathologic subtypes of MCDs in cortical tissue resected were then retrospectively correlated with in situ extraoperative ECoG patterns.

Results: Cortical areas with histopathologic subtype IIA showed significantly higher numbers of slow repetitive spike pattern in comparison with histopathologic type I (p = 0.007) and normal pathology (p = 0.002). The ictal onset came mainly from cortical areas with histopathologic type IIA (nine of 15 patients). None of the seizures originated from neocortical areas that showed BC-containing MCD (type IIB).

Conclusions: This study shows that areas containing BCs are less epileptogenic than are closely located dysplastic regions. These results suggest a possible protective effect of BCs or a severe disruption in the neuronal networks in BCs containing dysplastic lesions. Further studies are needed to elucidate the nature and the potential role(s) of balloon cells in MCD-induced epileptogenicity.

REFERENCES

1 Meencke HJ, Veith G. The relevance of slight migrational disturbances (microdysgenesis) to the etiologies of the epilepsies. Adv Neurol 1999; 79: 123–31.
CAS PubMed Google Scholar
2 Taylor DC, Falconer MA, Bruton CJ, et al. Focal dysplasia of the cerebral cortex in epilepsy. J Neurol Neurosurg Psychiatry 1971; 34: 369–87.
10.1136/jnnp.34.4.369
CAS PubMed Web of Science® Google Scholar
3 Raymond AA, Fish DR, Sisodiya SM, et al. Abnormalities of gyration, heterotopia, tuberous sclerosis, focal cortical dysplasia, microdysgenesis, dysembryoplastic neuroepithelial tumor and dysgenesis of the archicortex in epilepsy: clinical, EEG, and neuroimaging features in 100 adults patients. Brain 1995; 118: 629–60.
10.1093/brain/118.3.629
PubMed Web of Science® Google Scholar
4 Sisodiya SM. Surgery for malformations of cortical development causing epilepsy. Brain 2000; 123: 1075–91.
10.1093/brain/123.6.1075
PubMed Web of Science® Google Scholar
5 Mischel PS, Nguyen LP, Vinters HV. Cerebral cortical dysplasia associated with pediatric epilepsy: review of neuropathologic features and proposal for a grading system. J Neuropathol Exp Neurol 1995; 54: 137–53.
10.1097/00005072-199503000-00001
PubMed Web of Science® Google Scholar
6 Palmini A, Anderman F, Olivier A, et al. Focal neuronal migration disorders and intractable partial epilepsy: a study of 30 patients. Ann Neurol 1991; 30: 741–9.
10.1002/ana.410300602
CAS PubMed Web of Science® Google Scholar
7 Palmini A, Gambardella A, Anderman F, et al. Operative strategies for patients with cortical dysplastic lesions and intractable epilepsy. Epilepsia 1994; 35: S57–71.
10.1111/j.1528-1157.1994.tb05989.x
PubMed Web of Science® Google Scholar
8 Palmini A, Gambardella A, Anderman F, et al. Intrinsic epileptogenicity of human dysplastic cortex as suggested by corticography and surgical results. Ann Neurol 1995; 37: 476–87.
10.1002/ana.410370410
CAS PubMed Web of Science® Google Scholar
9 Rosenow F, Lüders HO, Dinner DS, et al. Histopathological correlates of epileptogenicity as expressed by electrocorticographic spiking and seizure frequency. Epilepsia 1998; 39: 850–6.
10.1111/j.1528-1157.1998.tb01179.x
CAS PubMed Web of Science® Google Scholar
10 Bronen RA, Vives KP, Kim JH, et al. Focal cortical dysplasia of Taylor, balloon cell subtype: MR differentiation from low grade tumor. AJNR Am J Neuroradiol 1997; 18: 1141–51.
PubMed Web of Science® Google Scholar
11 Najm IM, Ying Z, Babb T, et al. Epileptogenicity correlated with increased N-methyl-d- aspartate receptor subunit NR2A/B in human focal cortical dysplasia. Epilepsia 2000; 41: 971–6.
10.1111/j.1528-1157.2000.tb00281.x
CAS PubMed Web of Science® Google Scholar
12 Najm IM, Marusic P, Ying Z, et al. Focal cortical dysplasias in eloquent cortex: functional characteristics and correlation with MRI and histopathological changes. Epilepsia 2002; 43: 27–32.
10.1046/j.1528-1157.2002.00801.x
Google Scholar
13 Najm I, Bingaman W, Lüders H. The use of subdural grids in the management of focal malformations due to abnormal cortical development. Neurosurg Clin North Am 2002; 13: 87–92.
10.1016/S1042-3680(02)80009-2
PubMed Web of Science® Google Scholar
14 Palmini A, Luders H. Classification issues in malformations caused by abnormalities of cortical development. Neurosurg Clin North Am 2002; 13: 1–16.
10.1016/S1042-3680(02)80002-X
PubMed Web of Science® Google Scholar
15 Munari C, Francione S, Kahane P, et al. Usefulness of stereo EEG investigations in partial epilepsy associated with cortical dysplastic lesions and gray matter heterotopia. In: R Guerrini, ed. Dysplasias of cerebral cortex and epilepsy. Philadelphia: Lippincott-Raven, 1996: 383–94.
Google Scholar
16 Chassoux F, Devaux B, Landre E, et al. Stereoelectroencephalography in focal cortical dysplasia: a 3D approach to delineating the dysplastic cortex. Brain 2000; 123: 1733–51.
10.1093/brain/123.8.1733
PubMed Web of Science® Google Scholar
17 Dubeau F, Palmini A, Fish D, et al. The significance of electrocorticographic findings in focal cortical dysplasia: a review of their clinical, electrophysiological and neurochemical characteristics. Electroencephalogr Clin Neurophysiol 1998; suppl 48: 77–96.
Google Scholar

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Volume44, Issue1

January 2003

Pages 69-76

Epileptogenicity of Focal Malformations Due to Abnormal Cortical Development: Direct Electrocorticographic–Histopathologic Correlations

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Epileptogenicity of Focal Malformations Due to Abnormal Cortical Development: Direct Electrocorticographic–Histopathologic Correlations

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