Etiology and Pathology of Epilepsy

Epilepsy classification is essential to allow a common language among those who care for patients with epilepsy across the globe. Medications that are effective for epilepsy due to one etiology may be ineffective, or possibly exacerbate seizures, due to a different etiology. Patients with drug-resistant epilepsy due to focal cortical dysplasia (FCD) should be considered for focal respective surgery. Provoked seizures are distinguished from the unprovoked seizures that define epilepsy, with distinct prognosis and treatment. This chapter provides information on the novel classification scheme that classifies etiology as genetic, structural, metabolic, infectious, immune, or unknown. Epilepsy related to malformations of cortical development involves an imbalance between the excitatory and inhibitory neurotransmission and interactions between cell types. Localized malformations of cerebral cortex are FCD. These are further classified, based on histopathology.