Predictors of seizure freedom after surgery for malformations of cortical development
Version of Record online: 14 JUL 2011
Copyright © 2011 American Neurological Association
Annals of Neurology
Volume 70, Issue 1, pages 151–162, July 2011
How to Cite
Chang, E. F., Wang, D. D., Barkovich, A. J., Tihan, T., Auguste, K. I., Sullivan, J. E., Garcia, P. A. and Barbaro, N. M. (2011), Predictors of seizure freedom after surgery for malformations of cortical development. Ann Neurol., 70: 151–162. doi: 10.1002/ana.22399
- Issue online: 22 JUL 2011
- Version of Record online: 14 JUL 2011
- Accepted manuscript online: 18 FEB 2011 09:36AM EST
- Manuscript Accepted: 11 FEB 2011
- Manuscript Revised: 6 FEB 2011
- Manuscript Received: 9 AUG 2010
Malformations of cortical development (MCDs) are a major cause of medically refractory epilepsy. Our aim was to examine a surgical series of patients with cortical malformations to determine the prognostic factors associated with long-term seizure control.
We conducted a retrospective review of 143 patients with MCD who underwent resective surgery for medically refractory epilepsy. Demographic, imaging, histopathologic, and surgical variables were analyzed for potential association with seizure freedom. Preoperative magnetic resonance imaging (MRI) was evaluated in a blind fashion and classified according to a new imaging/embryologic MCD classification system.
Gray-white blurring on MRI, smaller lesions, complete resection of structural lesions, complete resection of abnormal electrocorticographic areas, and locally confined electrocorticographic abnormalities are favorable prognosticators of seizure freedom on univariate analysis. Imaging features consistent with abnormal proliferation (Barkovich class I) were associated with better outcome compared to those related to abnormal neuronal migration (class II) or abnormal cortical organization (class III). Multivariate logistic regression revealed complete resection of tissue manifesting electrocorticographic and/or MRI anatomic abnormalities as the main independent predictor of seizure freedom. Other histopathologic or demographic factors were not associated with seizure control. Long-term follow-up of patients demonstrated sustained overall rates of seizure control (72% at 2 years, 65% at 5 years, and 67% at 10 years).
Surgery for MCDs can result in high rates of seizure freedom. Complete resection of electrocorticographic and anatomic abnormalities appears to be most predictive of long-term seizure control. ANN NEUROL 2011