Abstracts

RATIONALE: At the end of this activity the participants should be able to describe the effectiveness and tolerability of vagus nerve stimulation for the treatment of medically refractory epilepsy in Rett syndrome.
METHODS: Four females with Rett syndrome and medically refractory symptomatic generalized epilepsy, age 1.5 to 14.5 years, had a vagus nerve stimulator implanted. Two of the subjects have received vagus nerve stimulation (VNS) for 3 months, one for one year, and one for two years. Neuropsychological testing including assessments of mood and alertness, the number and dosage of antiepileptic medication, percent decrease in seizure frequency, and utility of magnetic activation were assessed.
RESULTS: All four subjects demonstrated improved mood and alertness within the first month of VNS. The dosage of antiepileptic medication was reduced in all four subjects. The mean percent decrease in seizure frequency was 69.5% at 1 month and 79.2% at 3 months. In the two subjects undergoing VNS for one year, the mean percent decrease in seizure frequency was 83.5%. In the subject undergoing VNS for two years the mean percent decrease in seizure frequency was 100%. In all four subjects magnetic activation of the VNS aborted or diminished the duration of seizures 50% of the time.
CONCLUSIONS: Vagus nerve stimulation appears to be an effective long-term treatment for medically refractory epilepsy in Rett syndrome. Additional benefits of VNS in Rett syndrome are improved mood and alertness; these benefits occur independent of reduction in medication or decrease in seizure frequency.
[Supported by: Cyberonics]; (Disclosure: Grant - Cyberonics, Honoraria - Cyberonics)