Does classical semiology ("5As") predict post-operative seizure outcome in patients with temporal lobe epilepsy?

Temporal lobe epilepsy (TLE) accounts for 50%-70% of cases referred for epilepsy surgery. This study was designed to evaluate the distribution of the five hallmark seizure features-antecedent, aura, arrest, automatisms, and amnesia-considered collectively as the "5As," in individuals with temporal lobe epilepsy. We also analyzed the prognostic significance of 5As, if any, in predicting surgical outcome in drug-resistant TLE patients.

We included 684 patients who underwent clinical evaluation, neuropsychological assessment, high-resolution MRI, and VEEG monitoring followed by standard anterior temporal lobectomy between January 2009 and December 2018. Patients were followed up at 3, 12, and 36 months, and yearly thereafter after surgery. Outcomes were classified as "good" if patients remained seizure and aura-free, irrespective of medication, and "poor" if seizures of any type recurred post-operatively. The predictors determining the outcomes were analyzed using logistic regression, and Kaplan-Meier curves assessed the long-term seizure-free survival.

A total of 8456 VEEGs were done during this time period. Of them, 1747 were focal epilepsies; TLE were 1068, and surgical management was opted in 709 of them, of whom 684 patients formed this study cohort; 93.7% exhibited behavioral arrest, 88.6% had automatisms, 86.7% experienced amnesia, 74.6% reported auras, and 63.6% had antecedents (initial precipitating injury). All the classic semiological features (5 As) were present in 37.7%. At last follow-up, 47.8% had a good outcome at a mean follow-up of 75.6 months (maximum 14 years). Febrile seizures were associated with better seizure outcome (p = .021). Encephalitis (p = .026) and behavioral arrest (p = .006) were associated with poor outcome. No significant association was found between the presence of aura(s), automatisms, or amnesia with post-operative outcome.

A history of febrile seizures was linked to better post-operative outcomes, whereas encephalitis and behavioral arrest were associated with poorer prognosis. The presence or absence of any combination of classic features (5As) did not significantly affect the success of anterior temporal lobectomy.