Vagal nerve stimulator in childhood absence epilepsy: 2 case reports

Aim: Although most cases of childhood absence epilepsy (CAE) are effectually treated with one or more antiepileptic drugs (AEDs), treatment-resistant CAE occurs. Surgical treatment options in adult focal epilepsy include the implantation of a vagus nerve stimulator (VNS) as a neurostimulation procedure. Reports on VNS in CAE are limited. We present two children with drug-resistant CAE treated successfully by the implantation of a VNS.

Results: Our first female patient was diagnosed with CAE at the age of 5 years. The girl had 30 to 40 absence seizures up to a length of 60 seconds every day, despite the use of six different AEDs. The therapy with a corticosteroid drug as well as with ketogenic diet failed. We decided to implant a VNS at 2, 5 years after the onset of CAE. Only 1 month after VNS implantation, a significant reduction of frequency (approximately 60%) and duration of absence seizures was registered.

Our second female patient suffered from generalized tonic-clonic seizures and CAE since the age of 9 years. AEDs had minor effects. The disease deteriorated her quality of life considerably. At the age of 14 years school attendance was no longer possible because of high frequencies of absence seizures and because of the development of postictal cephalea after tonic-clonic seizures. Finally, we made the decision for VNS implantation. This therapeutic procedure resulted in significant less absence seizures and tonic-clonic seizures nearly disappeared, and could be interrupted by magnetic stimulation. Postictal cephalea disappeared completely, school attendance was now possible again.

Conclusion: Our experiences in two children lead us to believe that the implantation of VNS is a relevant treatment option in CAE. Although longtime results are missing, we endorse the proposal that VNS implantation should be incorporated into therapeutic regimens of drug-resistant CAE.