Abstracts

Rationale: Epilepsy surgery is a wide established measure in pharmaco-resistant focal epilepsies. Between 60 and 70% of patients are seizure free one year after surgery. There is little data about long-term seizure outcome and especially there is only little knowledge of shift of outcome classes during longterm follow up. We have analyzed this longterm outcome and specifically the stability and shift of outcome in respect of outcome classification. Methods: We analyzed the records of all consecutively operated patients with temporal lobe epilepsy operated on before May 1997 with a minimum follow up of 10 years. Follow up visits were 3 months, 6 months and then every follow up year post op. The outcome was defined by the Engel outcome classification and has been prospectively documented in the patient records. The outcome shift between the different outcome classes were analyzed year by year. Results: From 60 patients operated on 1996 and 1997 we had in 50 cases a complete 10 year follow up. In five additional patients the follow up was incomplete. 5 patients were lost. From these 50 patients 25 were men and 25 women. The average age of operation was 35.9 years. 35 patients had a mesio-temporal epilepsy and 15 temporo-lateral epilepsy. 15 patients had a hippocampal sclerosis, 13 hamartoma / DNET. The year-by-year analysis of outcome showed over the 10 years 74% to 78% in class I. After 10 years 48% of the patients were seizure free since surgery. From 12 cases qualified IA 6 months post op 5 changed to class IB and IC, 3 to class II, 1 to class III and 3 to class IV. From this class IV group 1 moved after 4 years back to class IC stable up to the end of 10 years. And 2 cases moved back to class III. Worsening of class II was distributed all over the 10 year follow up. Improvement of class II to class I was seen even after 6 years of follow up. After 10 years 39 patients were class I, 51% of them without drugs. Conclusions: We report about an excellent seizure outcome. During 10 years after surgery 48% of the patients are stable class IA since surgery. 40% are class I without medication. Even after 6 year of follow up there is an impressive improvement in seizure outcome possible.