Abstracts

Rationale: To describe the impact of Vagus Nerve Stimulator (VNS) on pediatric patients with diagnosis of primary generalized epilepsy (PGE) Methods: Retrospective chart review was conducted on patients who underwent VNS implantation from Jan 2011 to Dec 2015 at Children's Hospital of Pittsburgh. All patients had clinical diagnosis of PGE by treating epileptologists and had generalized spike-wave discharges on EEG. Patients with clear cognitive impairment, autism, or abnormal findings on brain MRI known to be associated with epilepsy were excluded. A patient with 15q11.2 deletion was kept in this study, as it was considered of unclear significance based on the parental testing. Results: Eleven patients (3 males) met inclusion/exclusion criteria. Epilepsy syndrome classifications included childhood absence (3), juvenile absence (3), juvenile myoclonic (4) and other (1). Median age of epilepsy diagnosis and VNS implant was 10 years (2-14) and 15 years (6-18), respectively. The patients were followed for a median of 1.6 years (0.6-7.8). The median number of AEDs tried prior to VNS was 4 (2-7). Valproic acid was not attempted on 55% (6/11).The reason for not attempted Valproic acid was POLG positive (2), parental preference (2) and was not documented in two patients. Mild learning difficulty or ADHD was present in 45% (5/11) of patients. The majority of patients (64%) had multiple daily seizures, and all patients had a seizure frequency of > 1/month prior to VNS implantation. All patients except one had generalized convulsive seizures. Seizure frequency improved at 1 year in 64% (7/11) of patients, including 6 patients with seizures = 1/month. None became seizure free. Age at VNS implantation (p=0.8) or epilepsy classification (p=0.5) was not associated with seizure improvement. Conclusions: VNS appears to improve seizure frequency in children with PGE, similar to that of drug-resistant focal epilepsy. Although all patients in our cohort failed more than 2 AEDs prior to VNS implant, valproic acid was not attempted in significant portion of patients. Funding: N/A