Abstracts

Rationale: To review our institutional experience with ROSA-guided EEG, its complications, and outcomes. Methods: The authors reviewed all SEEG cases at Saint Louis Children’s Hospital since starting in 2016. We reviewed patient demographics, types of seizure, auxiliary studies prior to SEEG, number of electrodes and total contacts placed, duration of SEEG study, ICU requirement/time post electrode placement, complication rate, time from SEEG electrode placement to intervention, number of patients proceeding to intervention, type of intervention used, lesional pathology (if available), frequency of seizures and number of AEDs prior to SEEG, at 6 months follow up and at the last visit. Results: Seventeen patient (12 female, 5 male) underwent SEEG electrode placement using ROSA system in our institution.  Average patient age was 13 years (range: 6-20). Seven patients had simple focal and 10 patients had complex partial seizures. All of the patients underwent MRI, scalp EEG and neuropsychological testing prior to the SEEG. Fourteen patients had PET, and 4 patients had SPECT prior to electrode placement. An average of 9 electrodes (104 surgical contacts) were placed. SEEG was recorded for an average of 5.8 days. Sixteen of the 17 patients went directly to the Neurology/Neurosurgery floor/EMU postoperatively while one patient with a small asymptomatic extraaxial hematoma that spontaneously resolved was observed in the ICU overnight. Seven patients had focal cortical dysplasia, four had tuberous sclerosis complex (TSC), one each with leptomeningeal angiomatosis, low grade glioma, and dysembryoplastic neuroepithelial tumor, and three patients did not have biopsy. Of seventeen patients, 14 proceeded to an intervention. In those patients, average time to intervention was 64 days. Six patients had laser interstitial thermotherapy (LITT), 6 patients underwent craniotomy, and one had a Neuropace device placed. One patient with tuberous sclerosis had 2 craniotomies, followed by LITT. Of the patients who underwent any sort of intervention and had at least 6-month follow-up (total of 11), seven had decreased seizure frequency and three patients were seizure free at 6 months. Three out of nine patients who both had intervention and at least 1-year follow-up were successfully weaned off one anti-seizure medication. Conclusions: The present study is a preliminary analysis limited by recent introduction of SEEG in our institution and lack of long-term follow up for some of the patients. SEEG has utility in treating pediatric epilepsy with a low rate of complications and limiting ICU time. The majority of patients who underwent intervention had reduction in seizure frequency and 30% of patients who had a one year follow up were on a decreased number of medications. Further work will help to delineate the utility of the SEEG in comparison to conventional grid placement. Funding: None