Diagnostic Yield of Noninvasive Presurgical Modalities in Drug Resistant Epilepsy: Concordance with Stereotactic EEG and Post-intervention Outcomes
Abstract number :
2.328
Submission category :
5. Neuro Imaging / 5B. Functional Imaging
Year :
2024
Submission ID :
273
Source :
www.aesnet.org
Presentation date :
12/8/2024 12:00:00 AM
Published date :
Authors :
Presenting Author: Ashar Farooqi, MBBS – Department of Neurology, Mayo Clinic, Rochester MN USA
Benjamin Brinkmann, PhD – Department of Neurology, Mayo Clinic, Rochester MN USA
Keith Starnes, MD – Mayo Clinic
Gregory Cascino, MD – Department of Neurology, Mayo Clinic, Rochester MN USA
Elson So, MD – Department of Neurology, Mayo Clinic, Rochester MN USA
Gregory Worrell, MD, PhD – Mayo Clinic
Brian Lundstrom, MD, PhD – Mayo Clinic
Terrence Lagerlund, MD, PhD – Department of Neurology, Mayo Clinic, Rochester MN USA
Anthony Fine, MD – Department of Pediatric Neurology, Mayo Clinic, Rochester MN USA
Elaine Wirrell, MD – Mayo Clinic
Kelsey Smith, MD – Department of Neurology, Mayo Clinic, Rochester MN USA
Katherine Nickels, MD, FAAN, FAES – Mayo Clinic
Nicholas Gregg, MD – Mayo Clinic
Kai Miller, MD, PhD – Mayo Clinic
Jamie Van Gompel, MD – Mayo Clinic
Richard Marsh, MD – Department of Neurosurgery, Mayo Clinic, Rochester MN USA
Robert Watson, MD, PhD – Department of Radiology, Mayo Clinic, Rochester MN USA
Katherine Noe, MD, PhD – Department of Neurology, Mayo Clinic, Scottsdale AZ USA
Anteneh Feyissa, MD – Mayo Clinic Florida
Jeffrey Britton, MD – Department of Neurology, Mayo Clinic, Rochester MN USA
Lily Wong-Kisiel, MD – Mayo Clinic College of Medicine
David Burkholder, MD – Mayo Clinic
Rationale: For patients with drug resistant epilepsy (DRE), stereotactically placed depth electrodes are increasingly used to identify seizure onset regions and target surgical and neuromodulation therapy. This study sought to assess the diagnostic yield of noninvasive pre-surgical studies with respect to stereotactic EEG (sEEG) findings and efficacy of surgical or neuromodulation intervention.
Methods: Consecutive patients undergoing sEEG monitoring to identify the origin of seizures at our institution between January 1, 2015, and December 31, 2021, were identified and medical records reviewed. Outcomes and rates of seizure freedom were evaluated in patients with at least 12 months of follow up, and rates of concordance between noninvasive presurgical studies and sEEG findings were evaluated and compared to post-intervention outcomes. Noninvasive presurgical modalities evaluated included 1.5 or 3.0 Tesla MRI, 7 Tesla MRI, PET, Ictal SPECT, MEG, ictal scalp video-EEG, interictal scalp video-EEG, ictal EEG source imaging (ESI), and interictal ESI.
Results: The study cohort consisted of 224 patients (44.0% female, age 3-66 years, median 26 years, 27.1% pediatric) who underwent 225 sEEG implantation surgeries in total and were monitored for 1-27 (Median 5) days. In 151 (67.4%) patients, focal seizure onset zones were identified; 63 (41.7%) mesial temporal, 11 (7.2%) neocortical, 5 (3.3%) both mesial and neocortical, 5 (3.3%) mesial frontal, 27 (17.9%) lateral frontal, 3 (2%) parietal, 3 (2%) occipital, 19 (12.6%) insula-operculum, 8 (5.3%) peri-rolandic, and 7 (4.6%) cingulate. In cases where intracranial monitoring confirmed definite focal onset seizures, the average number of noninvasive studies concordant with sEEG findings was significantly higher (3.5 vs. 1) compared to those with multifocal and diffuse onset. Though the percentage of individual noninvasive studies varies in different epilepsy types (Figure#1), as a cohort, MEG (38.0%) and Ictal ESI (38.3%) showed the highest rates of concordance with sEEG findings, while Ictal SPECT (25.4%) and PET (29.9%) showed the lowest rates of concordance. Eighty-four patients (37.5%) underwent resective surgery, 43 (19.2%) had laser interstitial thermal therapy (LITT), while 59 patients (26.3%) underwent neuromodulation. A total of 148 patients had at least 12 months of follow-up post-intervention; of these, 64 patients (43.2%) were seizure-free (ILAE #1) at the last follow-up.
Conclusions: Scalp video-EEG and brain MRI remain cornerstone evaluations for epilepsy. Noninvasive investigations such as SPECT, PET, MEG, and EEG source localization offer additional lateralizing and localizing information. In our cohort, DRE cases with sEEG-confirmed focal-onset seizures retrospectively had a higher number of noninvasive studies concordant with sEEG data. An increased number of concordant noninvasive studies can help formulate a clear implant hypothesis and guide the precise placement of electrodes on the selected cortical areas. Adequate sampling of functional abnormalities identified by these noninvasive studies can increase the probability of delineating a seizure onset zone with sEEG and ultimately determine the subsequent management of DRE.
Funding: NA
Neuro Imaging