Abstract Details

Title Enhanced Sensitivity of Electrocorticography During Awake Craniotomy Using a Novel Circular Grid Electrode

Topic Epilepsy/Clinical Neurophysiology (EEG)

Presentation(s) S29 - Epilepsy Diagnostics and Therapeutics (2:24 PM-2:36 PM)

Poster/Presentation
Number 008

Background Awake craniotomy with FBM neuropsychological testing is an important technique used to optimize resective brain surgeries near eloquent cortex. Awake craniotomy performed with ECoG and direct electrical stimulation (DES) for FBM can delineate eloquent cortex from lesions and epileptogenic regions. However, current electrode technology demonstrates spatial limitations. Our group has developed a novel circular grid with the goal of improving spatial recording of ECoG to enhance detection of ictal and interictal activity.

Objective To determine the utility of using a novel 22-contact circular grid for electrocorticography (ECoG) during intraoperative functional brain mapping (FBM) for awake craniotomy.

Design/Methods This retrospective study was approved by the institutional review board at Mayo Clinic Florida. We analyzed patients undergoing awake craniotomy with ECoG and DES and compared ECoG data obtained using the 22-contact circular grid to standard 6-contact strip electrode.

Results

We included 144 cases of awake craniotomy with ECoG, 73 using circular grid and 71 with strip electrode. No significant differences were seen regarding preoperative clinical and demographic data, duration of ECoG recording (p=0.676) and use of DES (p=0.926). Circular grid was more sensitive in detecting periodic focal epileptiform discharges (PFEDs) (p=0.004), PFEDs plus (p=0.032), afterdischarges (ADs) per case (p=0.022) at lower minimum (p<0.001) and maximum (p=0.002) intensity stimulation, and seizures (p=0.048). PFEDs (p<0.001), PFEDs plus (p<0.001), and HFOs (p<0.001) but not ADs (p=0.255) predicted electrographic seizures.

Conclusions We demonstrate higher sensitivity in detecting ictal and interictal activity on ECoG during awake craniotomy with a novel circular grid compared to strip electrode, likely due to better spatial sampling during ECoG. We also found association between PFEDs and intraoperative seizures.

Authors/Disclosures
Brin Freund, MD PRESENTER	Dr. Freund has received research support from Mayo Clinic.
Anteneh M. Feyissa, MD, MSc, FAAN (Mayo Clinic)	Dr. Feyissa has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Neurelis.
Aafreen Khan, MD	Dr. Khan has nothing to disclose.
Joseph I. Sirven, MD, FAAN (Mayo Clinic)	Dr. Sirven has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for UCB. Dr. Sirven has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for Neurelis. Dr. Sirven has received personal compensation in the range of $5,000-$9,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Neurona. Dr. Sirven has received personal compensation in the range of $10,000-$49,999 for serving as an Editor, Associate Editor, or Editorial Advisory Board Member for AAN. Dr. Sirven has received publishing royalties from a publication relating to health care. Dr. Sirven has received personal compensation in the range of $10,000-$49,999 for serving as a Host/ Co producer with WJCT Public Media. Dr. Sirven has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant with Federal Aviation Administration .
Sanjeet S. Grewal, MD	Sanjeet S. Grewal, MD has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Medtronic.
David Sabsevitz	No disclosure on file
Diogo Garcia	No disclosure on file
Alfredo Quinones-Hinojosa	No disclosure on file
William O. Tatum IV, DO, FAAN (Mayo Clinic)	Dr. Tatum has received personal compensation in the range of $10,000-$49,999 for serving as a Consultant for Bioserenity. Dr. Tatum has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Natus. Dr. Tatum has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Neurelis. Dr. Tatum has received personal compensation in the range of $500-$4,999 for serving as an Editor, Associate Editor, or Editorial Advisory Board Member for Elsevier. Dr. Tatum has received personal compensation in the range of $500-$4,999 for serving as an Expert Witness for Defense Law Firm on behalf of a patient with epilepsy with funds donated to the Epilepsy Foundation of America. The institution of Dr. Tatum has received research support from Esai. The institution of Dr. Tatum has received research support from Mayo Clinic. The institution of Dr. Tatum has received research support from Liva Nova. The institution of Dr. Tatum has received research support from Engage Pharmaceuticals. The institution of Dr. Tatum has received research support from Xenon. Dr. Tatum has received intellectual property interests from a discovery or technology relating to health care. Dr. Tatum has received publishing royalties from a publication relating to health care. Dr. Tatum has received publishing royalties from a publication relating to health care. Dr. Tatum has received publishing royalties from a publication relating to health care. Dr. Tatum has a non-compensated relationship as a AAN Section Chair of Clinical Neurophysiology with AAN that is relevant to AAN interests or activities.