Prognostic significance of acute postoperative seizures in extra-temporal lobe epilepsy surgery

OBJECTIVE: This study aims to assess the prognostic value of acute postoperative seizures (APOS) in patients surgically treated for drug-resistant extra-temporal lobe (ET) epilepsy. METHODS: We studied 77 consecutive patients with ET epilepsy who underwent epilepsy surgery and were followed up for at least 2 years (mean duration of follow-up 6.2 years, range 2-14). Medical charts were reviewed to identify APOS, defined as ictal events with the exception of auras occurring within the first 7 days after surgery. Seizure outcome was determined at annual intervals. Patients who were in Engel Class I at the last contact were classified as having a favourable outcome. RESULTS: Seizure outcome was favourable in 47 patients (61%). The occurrence of APOS and incompleteness of resection were found to be independently associated with unfavourable outcome in a multiple regression model including all preoperative factors identified as outcome predictors in univariate analysis. Duration of illness was the only independent preoperative predictor of APOS. CONCLUSIONS: Our study suggests that APOS may predict long-term outcome in patients undergoing resective surgery for ET epilepsy. Given some study limitations, our findings should be regarded as preliminary and need confirmation from future larger, prospective, multicentre studies. SIGNIFICANCE: Caution may be required in the clinical management of patients experiencing APOS.