Abstracts

Rationale: Epilepsy surgery provides long term seizure freedom in approximately 50% of children with intractable partial seizures. In patients who do not achieve seizure freedom, re-operation may improve outcomes. Few studies have examined the risks and benefits of repeat epilepsy surgery in children. This study aimed to evaluate the efficacy of repeat resective epilepsy surgery in achieving seizure freedom, the cost in terms of neurological deficits, and the most common etiology for repeat surgery. Methods: The study was a retrospective chart review of epilepsy surgery patients obtained prospectively from 2000 through 2013.Surgical pathology and MRI were used to determine epilepsy etiology. Clinic notes were reviewed to determine outcomes 6-12 months after last surgical procedure. Seizure freedom was classified based on the Engle criteria. Neurologic deficits following repeat surgery were noted. Results: Thirty-four of 271 (12.5%) patients underwent repeat resective epilepsy surgery (excluding corpus callosotomy and vagal-nerve stimulator patients). Cortical dysplasia was the most common etiology, identified in 61% (n=21) of repeat surgery patients. Most patients studied underwent cortical resections, with 23.5% (n=8) eventually undergoing hemispherectomy. Among all repeat epilepsy surgery patients, 44% (n=15) achieved Engle Class I and 29% (n=10) achieved Engle class II seizure control. Deficits following repeat surgery varied widely from no new deficit (n=8) to hemiparesis (n=11) or learning deficits (n=11), most commonly seen in hemispherectomy. Two patients experience mild language deficits. There was no difference in outcomes based on seizure etiology. There were no differences in outcomes based on age at time of surgery or time between surgical procedures. Conclusions: Our results demonstrate improved seizure control following repeat epilepsy surgery. A majority of patients in our database were able to achieve seizure freedom or significant improvement in seizure control. Observed deficits following repeat surgery ranged in severity, but many were improved with therapy as documented by neurology follow-up exams. Many of these deficits were predicted prior to surgery based on the location of the planned resection and were the reasons for conservative initial surgery. Careful consideration of risks and benefits are important when discussing additional surgery. These data indicate that repeat epilepsy surgery may be a viable option for children with refractory seizures following initial epilepsy surgery and may be necessary to achieve seizure freedom.