Epilepsy is a common condition affecting people of all ages, sex and socioeconomic status. Many patients with epilepsy, once diagnosed, can be successfully managed with anti-seizure medication (ASMs) [1]. However, up to 30–40% of patients will continue to have seizures despite optimal medical management [1]. Thus, the World Health Organization (WHO) estimates that 15 million people (of 50 million worldwide with epilepsy) will not achieve complete seizure freedom despite appropriate ASM therapy [2]. These patients consume more health care resources than those with well-controlled epilepsy, as the 15% who are most refractory account for ≥50% of the total costs of the disease [3].