To evaluate surgical outcomes in post-traumatic epilepsy (PTE) patients in relation to localization of the epileptogenic zone with stereo-electroencephalography (sEEG).
PTE patients have been thought to be poor surgical candidates due to multifocal areas of injury. sEEG has improved localization of the seizure foci.
All sEEG cases with traumatic brain injury (TBI) as a potential cause of epilepsy at two Level 4 Adult Epilepsy Centers were reviewed. Cases were included when TBI preceded epilepsy onset and loss of consciousness > 30 minutes or neuroimaging was consistent with prior trauma. Surgical outcomes at last follow up were analyzed.
15 patients met inclusion criteria. 7 out of 15 had electroclinical sEEG seizures originating from the hippocampus (6 unilateral, 1 bilateral). In the unilateral hippocampal subgroup, 3 of the 6 underwent destructive surgery (2–hippocampal laser ablation, 1–temporal lobectomy). 3 out of 3 were seizure-free with average 48-month follow-up (range 15-98). All 3 seizure-free patients have post-traumatic encephalomalacia (PE), but no seizures started from PE. 2 of the 6 had responsive neurostimulator (RNS) placed to the hippocampus, and 1 of the 6 refused surgery. Additionally, 7 out of 15 had electroclinical seizures originating from PE. 5 of the 7 had resection only, and 2 of the 7 had resection+RNS. None were seizure-free. In the resection only subgroup, outcomes varied (1-Engel Class 1B, 2-Engel class 2, 2-Engel class 3). In the resection+RNS group, one patient had >90%, and another had > 50% of seizure frequency reduction at 8 and 26-month follow up, respectively. Remaining 1 out of 15 had independent broad left and right temporal SEEG ictal onsets unrelated to PE and refused surgery.
PTE patients could have seizures starting from the hippocampus despite presence of PE, and these patients have more favorable destructive surgery outcomes than patients with seizure onset from PE.