Hello, everyone. My name is Jean-Paul Bryant, and I will be discussing Stereo-Electroencephalography, or SEEG, in pediatric epilepsy surgery. This is a five-year single-center experience at Nicholas Children's Hospital in Miami, Florida. So a little bit of background. Children undergoing surgery for medically refractory epilepsy typically require complex pre-surgical evaluation. This pre-surgical evaluation usually starts with non-invasive evaluation. However, if this cannot adequately localize the seizure onset zone, then further invasive testing is required. This invasive testing may include SEEG or subdural grid implantation, but there are drawbacks with each procedure. In subdural grid implantation in particular, a relatively large craniotomy is required, and there are complications associated with that, such as CSF leak or perhaps bone flap infection. Now, conventional wisdom has shown us that implanting patients who have had prior surgery may be difficult. So the goal of this study was to describe our cohort and also to see if SEEG is still a safe and efficacious procedure in children with very complex, very refractory epilepsy, many of which who have had prior surgery. This was a retrospective chart review of 40 patients who underwent SEEG between April 2015 and September 2020, a five-year span. So these patients were presented at epilepsy conference and were deemed suitable candidates for SEEG if they had complex refractory epilepsy, if they had a suspected deep area of focus, if they needed bilateral investigations, or perhaps if they had previous surgical intervention. They then underwent the SEEG procedure using a frame-based stereotactic technique with navigation in order to help plan the trajectory of depth electrode placement. The data was then subsequently compiled and analyzed, and then many of this cohort underwent subsequent surgical intervention. Now, to talk a little bit about the demographics of our cohort, the average age of seizure onset was about 6.2 years, and about 70% of these patients were experiencing complex partial seizures. About half, exactly 18 of these patients, had surgery prior to the SEEG procedure. Now, the average days of implantation of depth electrode placement was about 5.6 days. And that was about seven depth electrodes placed per patient, which is a value that is substantially lower than others described in the literature. And this led to a total of 269 depth electrodes placed throughout the five-year period. Now, we did have two complications. One was clinically insignificant evidence of radiographic subarachnoid hemorrhage. The other was due to extensive scarring of the dura. So when the depth electrode was attempted for placement, it bounced off the dura and into the epidural space, resulting in a clinically non-relevant, insignificant epidural hematoma. And about 40% of these patients underwent subsequent surgical resection. In conclusion, our experience parallels outcomes from other centers, but it is important to note that at NICLAS, we do receive a very large volume of complex cases involving children who have had prior surgery, or perhaps prior two-stage grit implantation, and who have complex, very refractory epilepsy. We did see that SEEG was still a safe and effective method for electrophysiological evaluation in these patients with a low complication rate. Now, NICLAS has an ongoing robotic series to develop a longitudinal study comparing both robotic and non-robotic procedural outcomes. Thank you for listening to this talk, and I would like to thank my mentors for helping me and guiding me with this project. Thank you.

Stereo-Electroencephalography

pediatric epilepsy surgery

Nicholas Children's Hospital

Miami, Florida

SEEG procedure