Spatial variation in high-frequency oscillation rates and amplitudes in intracranial EEG

Hari Guragain, Jan Cimbalnik, Matt Stead, David M. Groppe, Brent M. Berry, Vaclav Kremen, Daniel Kenney-Jung, Jeffrey Britton, Gregory A. Worrell, Benjamin H. Brinkmann

Research output: Contribution to journalArticlepeer-review

19 Scopus citations

Abstract

Objective To assess the variation in baseline and seizure onset zone interictal high-frequency oscillation (HFO) rates and amplitudes across different anatomic brain regions in a large cohort of patients. Methods Seventy patients who had wide-bandwidth (5 kHz) intracranial EEG (iEEG) recordings during surgical evaluation for drug-resistant epilepsy between 2005 and 2014 who had high-resolution MRI and CT imaging were identified. Discrete HFOs were identified in 2-hour segments of high-quality interictal iEEG data with an automated detector. Electrode locations were determined by coregistering the patient's preoperative MRI with an X-ray CT scan acquired immediately after electrode implantation and correcting electrode locations for postimplant brain shift. The anatomic locations of electrodes were determined using the Desikan-Killiany brain atlas via FreeSurfer. HFO rates and mean amplitudes were measured in seizure onset zone (SOZ) and non-SOZ electrodes, as determined by the clinical iEEG seizure recordings. To promote reproducible research, imaging and iEEG data are made freely available (msel.mayo. edu). Results Baseline (non-SOZ) HFO rates and amplitudes vary significantly in different brain structures, and between homologous structures in left and right hemispheres. While HFO rates and amplitudes were significantly higher in SOZ than non-SOZ electrodes when analyzed regardless of contact location, SOZ and non-SOZ HFO rates and amplitudes were not separable in some lobes and structures (e.g., frontal and temporal neocortex). Conclusions The anatomic variation in SOZ and non-SOZ HFO rates and amplitudes suggests the need to assess interictal HFO activity relative to anatomically accurate normative standards when using HFOs for presurgical planning.

Original languageEnglish (US)
Pages (from-to)E639-E646
JournalNeurology
Volume90
Issue number8
DOIs
StatePublished - Feb 20 2018
Externally publishedYes

Bibliographical note

Funding Information:
in Prague, Czech Republic, and the Czech Science Foundation: grant 17-20480S. J.C. is supported by the European Regional Development Fund–Project FNUSA-ICRC (CZ.1.05/1.1.00/ 02.0123) and MEYS CR (LH15047, KONTAKT II).

Funding Information:
This study was funded by Mr. and Mrs. David Hawk, the NIH, and the Mayo Clinic. Some authors report having research relationships with Medtronic and NeuroOne. Go to Neurology.org/N for full disclosures.

Funding Information:
This study was supported by a gift from Mr. and Mrs. David Hawk, The NIH (NINDS-R01-NS63039, NINDS-R01-NS78136), and the Mayo Clinic. V.K. is also supported by institutional resources for research by Czech Technical University

Funding Information:
This study was supported by a gift from Mr. and Mrs. David Hawk, The NIH (NINDS-R01- NS63039, NINDS-R01-NS78136), and the Mayo Clinic. V.K. is also supported by institutional resources for research by Czech Technical University in Prague, Czech Republic, and the Czech Science Foundation: grant 17-20480S. J.C. is supported by the European Regional Development Fund-Project FNUSA-ICRC (CZ.1.05/1.1.00/ 02.0123) and MEYS CR (LH15047, KONTAKT II).

Publisher Copyright:
© 2018 American Academy of Neurology

Fingerprint Dive into the research topics of 'Spatial variation in high-frequency oscillation rates and amplitudes in intracranial EEG'. Together they form a unique fingerprint.

Cite this