Abstracts

Rationale: Children suffer from drug resistant epilepsy (DRE) in disproportionate numbers as compared to adults and often are identified as having a specific epilepsy syndrome or encephalopathy that presents at an early age and quickly become intractable. These include infantile spasms and Lennox-Gastaut syndrome. Therapeutic epilepsy surgery (resection or ablation) is one option for treatment in this population. The RNS System has been extensively tested in adults with DRE but has not been FDA approved for use in patients under the age of 18.  Methods: We reviewed the charts of patients under the age of 18 implanted with the RNS System from 2015 to 2019. The diagnostic evaluation and treatment plan for the patients described in this report were reviewed in a multidisciplinary epilepsy surgery case conference at the Mount Sinai Health Systems in New York City. Approvals for off-label RNS System treatment were obtained from each patient's insurance company. Pathology and genetic testing results, when available, were analyzed.  Results: Fourteen patients under the age of 18 were treated with the RNS System from 2015 to 2019. Follow up time ranged from 12 days to 32 months. Median age at surgery was 12 years old  (range 9-17) and average length of time from epilepsy diagnosis to time of placement of the RNS System was 11.8 years. All children were developmentally delayed, ranging from mild LD to severe IDD and autism. There was one adverse event associated with RNS System implantation- infection treated with antibiotics (did not require removal of system or surgical intervention.)  There was a decrease in seizure frequency in most patients, ranging from 25% - 100%.  Two were seizure free. No child experienced an increase in seizure activity. In some cases, more than 2 leads implanted and there were changes in leads being recorded and stimulated in 3casesIn one case, in which the RNS System had been placed based on old grid and strip data, the stimulator was removed, SEEG performed and the patient is awaiting possible RNS System replacement.  Conclusions: The RNS System demonstrated safety and efficacy in this group of 14 children with DRE. The RNS System should be considered when a patient is not a surgical candidate or surgery does not achieve anticipated outcomes. Surgical intervention to provide neuromodulation or therapeutic epilepsy surgery should be considered early after the diagnosis of epilepsy. Further analysis will take place in the next 6 months.  Funding: No funding