Abstracts

Rationale: Epilepsy surgery for temporal lobe epilepsy could be performed through standard temporal lobectomy (STL) and selective amygdalohippocampectomy (SA). Pre-operation intracranial EEG (IEEG) is a common pre-operation evaluation in temporal lobe epilepsy. It is still uncertain that IEEG correlates of different type of epilepsy surgery and seizure outcome in temporal lobe epilepsy. Methods: A retrospective study was done to analyze the patients with mesotemporal lobe epilepsy from 1992 to 2012 at DHMC. All of the patients in the study have refractory temporal lobe epilepsy with MRI evidence of mesial temporal sclerosis. 104 patients was included in the study to analyze the relationship of IEEG, surgery type and seizure outcome. Results: 69 patients were seizure free (Engel class I) and 35 patients were not seizure free (Engel class II or above) after epilepsy surgery. 83% patients with STL were seizure free and 54% patients with SA were seizure free. There is significant difference between STL and SA group in seizure outcome (P < 0.001). 51 patients MLE underwent IEEG and 53 patients did not have IEEG before epilepsy surgery. 62% patients with IEEG were seizure free after surgery and 69% patients without EEG were seizure free after epilepsy surgery. No significant effect of IEEG in seizure outcome was found in the study. However, IEEG is significantly correlated with STL. The patients with IEEG underwent STL more than the patients without IEEG. Conclusions: MTS patients with STL have better seizure outcome as compared to SA. IEEG combined with STL might predict seizure outcome in temporal lobe epilepsy. Our study provide insight into different types of temporal lobe epilepsy surgery and IEEG. Funding: Diamond research foundation at Dartmouth Hitchcock Medical Center