Abstracts

Rationale: Brain trauma is a significant risk factor for epilepsy. Post traumatic epilepsy can be refractory to anti-epileptic drugs, making surgical treatment a potential treatment option. While post traumatic pathology is often extra-temporal, little has been reported in success rates of surgical evaluation and treatment of extra-temporal post traumatic epilepsy. Here we report a large series of such cases. Methods: We performed a retrospective review of patients who had video EEG monitoring done at University of Washington Regional Epilepsy Center at Harborview and University of Washington between 1990 and 2007. We identified subjects who: 1) had a clear history of antecedetal head trauma, 2) no other plausible etiology for their epilepsy, and 3) age 18 at the time of monitoring. Results: Overall, 371 patients met these criteria. A total of 99 patients were offered surgery. Seventy seven (77) had temporal lobe resection, the remainder had some resection of extra temporal regions (with or without inclusion of some temporal lobe). Of the 32 patients 7 were found to have pathological evidence of another process (such as dysplasia) after resection. Of the remaining 25 patients, 20 had invasive monitoring. Among these, 24% were seizure free on long term follow up. Altogether, about half of the patients have had a favorable outcome with no or less than 2 seizures per year. Surgical procedures were considered challenging due to presence of adhesions and prior surgery and brain injury. Complications included post-implantation subdural hematoma requiring evacuation (1 case), post-operative infection requiring absecss drainage (1 case), and occurence of both (1 case). Factors associated with good outcome included frontal lobe resection, concordance of EEG and MRI, and late age of onset for trauma. Conclusions: A significant portion of post-traumatic intractable epilepsy appears to be extra-temporal. Surgical treatment of extra-temporal post traumatic epilepsy is feasible and relatively safe and overall has similar outcome to extra-temporal lobe resections. Seizure freedom rate is lower than many other groups with more focal pathology. Distinction of these groups and resection often require invasive monitoring, which in this population is challenging and carries a risk of complictions in a minority of patients.