Abstracts

Rationale: We studied patients with post-traumatic temporal lobe epilepsy (TLE) who had epilepsy surgery. We examined the frequency of mesial and neocortical temporal seizure subtypes and the age of trauma to determine whether these factors influenced outcome. Methods: We reviewed 18 consecutive cases of surgically treated post-traumatic TLE. All patients had head trauma that resulted in hospitalization, loss of consciousness, or coma and preceded the onset of epilepsy. Patients with other definite risk factors for epilepsy were excluded. Age at trauma ranged from birth to 38 years (mean = 15.2 years). Workup for all patients included MRI, neuropsychological testing, Wada testing, intracranial EEG monitoring, and histopathologic analysis of resected tissue. Patients were followed for at least six months postoperatively (mean = 34 months) and surgical outcome was based on Engel's classification. Results: Using intracranial EEG, MRI, and pathology review we classified 12 patients as neocortical TLE (NTLE) and 6 as mesial TLE (MTLE). 6/6 MTLE and only 1/12 NTLE patients had hippocampal atrophy on MRI. 11/12 NTLE patients achieved Class I outcomes and 1/12 Class II, whereas 2 MTLE patients had Class I, 2 had Class II and 2 had Class III-IV outcomes. Of the patients with MTLE, 2 had trauma before age 5 and 4 had trauma after age 5. Of the 2 MTLE patients with early head trauma, 1 had a Class I outcome and 1 had Class II. Of the 4 MTLE patients with trauma after age 5, only 1 achieved a Class I outcome. Conclusions: In contrast to previous reports, head trauma does not predict a poor surgical outcome in well-selected patients, particularly those with NTLE. Additionally, MTLE with MRI evidence of hippocampal atrophy occurred in some patients suffering trauma after age 5, but did not always predict excellent surgical outcome.