Abstracts

Intractable epilepsy with head trauma (HT) as risk has been associated with both mesial temporal (MTLE) and neocortical localization (NE). There is limited information on the semiology, ictal and interictal EEG characteristics of post-traumatic epilepsy (PTE). We wished to review the ictal features of our cohort with medically intractable PTE undergoing epilepsy surgery. The epilepsy surgery database from Henry Ford Hospital was reviewed to identify those individuals who underwent epilepsy surgery with a minimum of 1 year follow-up and whose sole risk factor for epilepsy was HT. Each monitoring was reviewed in a blinded fashion for: seizure (Sz) type, Sz onset location, Sz onset frequency, and Sz duration. Semiology was classified as suggestive of MTLE or NE and combined with noninvasive ictal and interictal EEG localization to form an overall impression of noninvasive monitoring as being MTLE, NE or unclear localization. Interhemispheric propagation times (IPT), and presence of ictal spiking (IS) was determined from invasive recordings. Age at HT, duration of epilepsy, surgical procedure performed, Sz outcome as of last follow up was determined. A database was created. Statistics used included Student t-test and Chi-square. Thirty six patients were identified from the database; 3 were excluded due to missing EEG data, and 1 for prior resection. All underwent noninvasive monitoring and 24 invasive monitoring. A total of 653 Sz were reviewed. Ten had recorded simple partial Sz, 33 complex partial Sz, 19 generalized tonic clonic Sz, and 19 subclinical Sz (SCSz). Summarized ictal features of both groups are presented in the table. Review of noninvasive impression indicated 20 with MTLE, 10 NE, and 6 unclear localization. Impression was compared to ultimate localization and was correct for 19/20 with MTLE, all with ES, and 4/6 which were unclear localized to MTLE. Twenty three underwent anterior temporal lobectomy (ATL) with 15 Engel Class I; 13 underwent various neocortical resections with 4 Engel Class I. The ATL group was more likely to have Engel Class I outcome (p[lt]0.05). Neither age at HT or duration of epilepsy correlated with outcome for either MTLE (p=0.63, p=0.57) or NE (p=0.72, p=0.58). Noninvasive EEG and semiology correctly differentiated MTLE from NE in the majority with PTE. No ictal feature predicted good seizure outcomes. Those who underwent ATL were more likely to be seizure free. Age at HT and duration of epilepsy did not impact outcome or localization.[table1]