Outcome with respect to seizures as a percentage of patients in different Engel’s classes at different time intervals. Outcome with respect to seizures as a percentage of patients in different Engel’s classes at different time intervals. (A) All patients with unilateral temporal lobe epilepsy (mean follow up 5.4 years). (B) Patients with unilateral temporal lobe epilepsy imaged without a specified magnetic resonance (MR) imaging protocol (1988–1993; median follow up 7.7 years). (C) Patients with unilateral temporal lobe epilepsy imaged with a standardised MR imaging protocol (1993–1999; median follow up 3.8 years). (D) All palliatively operated temporal lobe epilepsy patients (mean follow up 4.4 years). (E) Palliatively operated temporal lobe epilepsy patients imaged without a specified MR imaging protocol (1988–1993; median follow up 5.9 years). (F) Palliatively operated temporal lobe epilepsy patients imaged with a standardised MR imaging protocol (1993–1999; median follow up 3.1 years). Auras only, seizure-free patients with postoperative auras only; Engel II, rare seizures (fewer than three seizures a year); Engel III, worthwhile seizure reduction (a reduction in seizure frequency of at least 80%); Engel IVA, patients with a seizure reduction of at least 50%; Engel IVB-C, no change in seizure frequency, or more frequent seizures (n = 1); latest, latest available follow up data; mo, months; SF, completely seizure-free patients; y, years. L Jutila et al. J Neurol Neurosurg Psychiatry 2002;73:486-494 ©2002 by BMJ Publishing Group Ltd