Refractory epilepsy: a clinicopathologic study of 273 consecutive cases

Objective To investigate the elinieopathologie features of refractory epilepsy. Methods The clinical and pathologic features of refractory epilepsy of 273 cases undergoing surgical treatment in Xuanwu Hospital from January 2005 to December 2007 were reviewed retrospectively. Results The mean age of seizure onset and disease duration were 11.0 years and 11.2 years respectively. The following pathologic subgroups were identified: malformation of cortical development (MCD, 158/273) including focal cortical dysplasia (FCD) type Ⅰ (104, the mean age of seizure onset and disease duration were 11.1 years and 11.2 years respectively), FCD type Ⅱ (30, the mean age of seizure onset and disease duration were 7. 9 years and 12. 7 years respectively) , mild MCD (6) , tuberous sclerosis complex (6) and other types (9) , brain turnouts (26/273, the mean age of seizure onset and disease duration were 14. 5 years and 6. 3 years respectively), ulegyria (63/273), brain infections (13/273), vascular malformation (3/273), cyst (3/273), cholesteatoma (1/273) and other unknown types (6/273). Dual pathology was identified in 31 of 158 MCD cases. Eighty-six of 134 (64. 2%) FCD cases were type Ⅰ B predominantly seen in temporal lobe. Twenty of 26 (76. 9%) brain tumours were mixed neuronal-glial tumours predominantly located in temporal lobe. Cortical dysplasia was often seen in these cases. Conclusions The 3 most common causes of refractory epilepsy are MCD, ulegyria and brain tumours. The predominant subtype of FCD is type Ⅰ B often located in temporal lobe, in which associated hippoeampal sclerosis is often seen. Brain tumors in patients with refractory epilepsy are almost benign neoplasms located in temporal lobe, in which the most frequent type is mixed neuronal-glial tumour. Key words: Epilepsy ;  Malformations of cortical development;  Glioma