Long-term seizure outcome after resection surgery for temporal lobe epilepsy: Comparison between postoperative 2 and 7 years

Favorable short-term outcome is reported for the resective surgery in patients with temporal lobe epilepsy (TLE). However, few authors have demonstrated the long-term outcome up to the present. We evaluated the long-term seizure outcome of the patients after anterior temporal lobectomy with hippocampectomy for intractable TLE. Twenty seven patients who underwent the resection surgery between September 1994 and November 1999 and were followed up for more than 7 years after the surgery participated in this study. The outcome of the each patient was classified at the time of 2 and 7 years after the surgery, according to the Engel's classification. Among 13 cases with medial TLE which is associated with hippocampal sclerosis, 12 and 10 cases were classified into class I and IA, respectively at the time of postoperative 2 years. Meanwhile, 11 and 3 cases were classified into class I and IA at 7 years. Among 8 cases with lesional TLE, 6 and 4 cases were classified into class I and IA at the time of 2 years, which is the same 7 years later. In 6 cases with lateral TLE, 2 and 1 cases were classified into class I and IA both 2 and 7 years after the surgery. Antiepileptic drugs (AEDs) were completely discontinued in 4 cases (15%). In conclusion, although postoperative seizure outcome doesn't differ so much between 2 and 7 years after the surgery, the number of patients with complete seizure free (Engel's calss IA) falls off 7 years later, which were mostly due to the decrease or discontinuation of AEDs.