Stereo-electroencephalography Guided Laser Ablation in Neocortical Epilepsy: Electrophysiological Biomarker and Seizure Outcome
Abstract number :
2.284
Submission category :
9. Surgery / 9A. Adult
Year :
2022
Submission ID :
2204325
Source :
www.aesnet.org
Presentation date :
12/4/2022 12:00:00 PM
Published date :
Nov 22, 2022, 05:24 AM
Authors :
Olesya Grinenko, MD, PhD – Mercy Health Saint Mary's; Thandar Aung, MD, MS – Epilepsy Center – University of Pittsburgh Medical Center; Jian Li, PhD – . Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School; John Mosher, PhD – McGovern Medical School, The University of Texas Health Science Center at Houston, Houston; Patrick Chauvel, MD – University of Pittsburgh Medical Center; Jorge Gonzalez-Martinez, MD, PhD – University of Pittsburgh Medical Center
Rationale: Compared to resective epilepsy surgery, laser interstitial thermotherapy (LiTT) is intended to be a less morbid approach, but the efficacy of this treatment in neocortical epilepsy still requires validation. We previously identified a time-frequency pattern as a biomarker of the epileptogenic zone (EZ). This study aims to test if we can use this biomarker to select patients who would benefit from LiTT treatment.
Methods: We analyzed the 16 consecutive patients with neocortical drug-resistant epilepsy who underwent LiTT. The seizure onset zone (SOZ) was identified by visual analysis of the SEEG. We also identified predicted EZ (PEZ) by applying the “EZ Fingerprint” pipeline previously developed and tested on a group of seizure-free patients. Subsequently, we identified the “ablated contacts” within PEZ or SOZ and correlated the completeness of ablation of those contracts with seizure outcomes based on the latest follow-up.
Results: Thirteen patients had fast activity (FA) at seizure onset, and eleven had predicted EZ. Three patients had seizure onset without FA. In those patients, only SOZ was analyzed. Complete ablation of PEZ was performed in two patients: those patients remained seizure-free at the latest follow-up (46 and 40 months). Five patients with partially ablated PEZ achieved seizure freedom from 16 to 44 months. In five patients, ablation was performed outside PEZ: Seizures reoccurred in these patients within 9 months for one patient and 1 month or less for four patients. Partial ablation of SOZ was associated with seizure freedom for 40 months in one patient and 1 month or less in four patients.
Conclusions: Partial or complete ablation of PEZ identified based on the time-frequency pattern predicts favorable seizure outcome after LiTT. Failure to identify PEZ or only SOZ ablation was associated with poor outcomes in the majority of cases. The results highlight the value of using EZ Fingerprint biomarker and the importance of adequate electrode placement for optimal localization of volumetrically restricted epileptogenic zones, making SEEG-guide laser therapy a suitable treatment option in neocortical epilepsy.
Funding: None
Surgery