The duration of temporal lobe epilepsy and seizure outcome after epilepsy surgery

To assess the effect of the duration of epilepsy on the outcome of epilepsy surgery in non-lesional medically refractory temporal lobe epilepsy we reviewed the outcome of 76 patients.

All patients had anterior temporal resections for "non-lesional" temporal epilepsy (excluding any patient with tumours or vascular malformations but including patients with hippocampal sclerosis). Outcome at one year was assessed using Engel's scale.

67% had a good outcome (Engel I or II). The mean duration of epilepsy was 23.0 years (range 2.9-46.9 years). Overall, there was no significant difference between patients with good outcome (mean duration 22.4 years) and poor outcome (mean duration 24.2 years) (p=0.49). The proportion of patients with good outcome was slightly higher in the shorter duration groups. (Duration less than 10 years 75%, 10-19 years 71%, 20-29 years 65%, 30-39 years 62%, and 40-49 years 60% good outcome, p=0.95).

We found no significant associations between outcome and duration of epilepsy.