Authors :
Presenting Author: Efstathios Kondylis, MD – Cleveland Clinic
Juan Bulacio, MD – Cleveland Clinic
Baltazar Zavala, MD, PhD – Cleveland Clinic
Stephen Harasimchuk, R. EEG T. – Cleveland Clinic
Richard Rammo, MD – Cleveland Clinic
William Bingaman, M.D. – Cleveland Clinic Epilepsy Center, Cleveland Clinic Foundation, Cleveland, OH, USA
Demitre Serletis, MD, PhD – Cleveland Clinic
Rationale:
Stereoelectroencephalography (sEEG)-guided radiofrequency ablation (RFA) uses sEEG electrodes implanted for seizure evaluation to create tissue lesions. The procedure serves as a diagnostic test of the localization hypothesis, with some potential therapeutic benefit. Previously, sEEG-guided RFA was performed without temperature monitoring. The FDA has recently cleared a new system capable of monitoring and controlling ablation temperature in real-time (NeuroOne, K231675). Here we describe the first clinical use of this system at our center.
Methods:
We report on two adult patients undergoing sEEG-guided RFA using the new FDA-approved technology featuring real-time temperature monitoring. Average patient age was 25.5 years. Both patients were female. MRI was non-lesional in both cases. The first patient had left hemispheric epilepsy, with PET, SPECT and MEG localization to the basal occipitotemporal region. The second patient had left hemispheric epilepsy, with non-focal PET but MEG clustering in the left peri-rolandic region. Each patient underwent left-sided sEEG, followed by RF ablation to dedicated contact sites.
Results:
Robotic-guided sEEG was performed (ROSA, Zimmer Biomet), with 17 and 13 left-sided NeuroOne electrodes implanted in each patient, respectively. Patients were monitored for an average of 10.5 days. Diagnostic sEEG-guided RFA was proposed in both patients on the basis of excellent localization of early seizure organization to specific electrode contacts. Treatment contact sites were assessed to rule out proximity to critical vessels (at least 1-2 mm away). All ablations were performed in the OR. The first patient received 4 ablations using the OneRF platform (NeuroOne), delivered to sequential contact pairs along 2 electrodes traversing the lateral occipitotemporal sulcus. The second patient received a total of 3 ablations along 1 single electrode trajectory within a small sulcus in the post-central gyrus. Real-temperature tracking was used, delivering each ablation at 85°C for 3-5 minutes in duration, in bipolar configuration. Plateauing of lead impedances was observed. Intra-operative electrocorticography confirmed localized improvement in treated contact recordings. The procedure was well-tolerated by both patients under awake conditions. Post-treatment, CT (same day) and MR imaging (post-operative day #1) captured good treatment effect. Average ablation size ranged from 7-8 mm in diameter. Both patients were explanted and discharged in stable condition, the following day.
Conclusions:
sEEG-guided RFA is a pivotal tool in the diagnostic (and potentially therapeutic) toolbox of neurosurgeons and epileptologists. We report here on successful sEEG-guided RFA in two patients (total of 7 lesions), using a new FDA-cleared technology. The new system was safe and easy to integrate in the operative workflow. Real-time temperature monitoring allowed for precise, controlled lesions while avoiding injury to critical structures. Future work and longer follow-up will characterize optimal parameter selection leading to lesion customization (including size) in human brain tissue, while also highlighting the efficacy of sEEG-guided RFA with this device.
Funding: None.