Assessment of the response to antiepileptic drugs in epileptic patients with structural lesion(s) on neuroimaging

Abstract

Abstract Background Focal epilepsy is the most common form of epilepsy in adults. Advances in brain imaging allowed better identification of different structural lesions underlying focal epilepsy. However, the response to antiepileptic drugs in lesional epilepsy is heterogeneous and difficult to anticipate. This study aimed to evaluate the response to antiepileptic drugs (AED) in patients with lesional epilepsy and to identify the predictors for poor seizure control. Methods One hundred and sixty-five patients with lesional epilepsy were included; the clinical diagnosis of epilepsy and seizure classification was based on the revised criteria of the International League Against Epilepsy (ILAE). Patients were subjected to full clinical assessment, MRI brain imaging epilepsy protocol, and EEG monitoring. All subjects were followed in the epilepsy clinic for at least 6 months. Results 75.8% of patients with lesional epilepsy showed poor response to antiepileptic medications. Cerebromalatic lesions related to brain trauma was the most frequently encountered (21.8%). Malformations of cortical development were significantly associated with poor response to AED (p = 0.040). Polytherapy and the combined use of 1st- and 2nd-generation AED were higher in the poor response group. Logistic regression analysis revealed that younger age at seizure onset and abnormal EEG findings was 0.965 times and 2.5 times more associated with poor seizure control, respectively. Conclusion This study revealed that patients with lesional epilepsy who develop seizures in their early life, who suffer from malformations of cortical development, or who show abnormal EEG findings are more suspected to show poor response to AED.