Bell GS, et al. - Researchers carried out this study to determine which preoperative factors were correlated with postoperative seizure outcome. They concluded that readily identified clinical features and investigations were correlated with the reduced probability of good outcome and needed consideration when planning pre surgical evaluation.

• In this study, the researchers observed seizure outcome of 693 adults who had resective epilepsy surgery between 1990 and 2010.
• They used survival analysis to detect preoperatively identifiable risk factors of poor seizure outcome.

• In this study, 7 factors were significantly correlated with increased probability of recurrence of seizures with impaired awareness postsurgery: MRI findings (eg, HR adjusted for other variables in the model 2.5; 95% CI 1.6 to 3.8 for normal MRI than hippocampal sclerosis), a history of secondarily generalised convulsive seizures (2.3; 95% CI 1.7 to 3.0 for these seizures in the previous year vs never), psychiatric history (1.3; 95% CI 1.1 to 1.7), learning disability (1.8; 95% CI 1.2 to 2.6) and extratemporal (vs temporal) surgery (1.4; 95% CI 1.02, 2.04).
• Higher probability of seizure recurrence was seen in people with an older onset of epilepsy (1.01; 95% CI 1.00, 1.02) along with those who had used more antiepileptic drugs (1.05; 95% CI 1.01 to 1.09).
• Combinations of variables correlated with seizure recurrence presented overall low probabilities of 5-year seizure freedom (eg, a normal MRI and convulsive seizures in the previous year has a probability of seizure freedom at 5 years of approximately 0.19).