Oral Presentations 2022 AANS Annual Scientific Meeting

Introduction: Endovascular electroencephalography (evEEG) utilizes the cerebrovascular system as a minimally-invasive conduit to record electrical activity from adjacent neural structures, mitigating the poor spatial resolution and risks of open craniotomy associated with extracranial EEG and electrocorticography, respectively.The safety, feasibility, and efficacy using the Woven Endobridge (WEB) intracranial aneurysm embolization device for evEEG has yet to be investigated in humans.Methods: Fifteen patients undergoing awake endovascular treatment of unruptured cerebral aneurysms via WEB device were included.The WEB Device, composed of nitinol with a platinum core, served as a single-electrode intravascular contact by connecting its distal deployment wire to an EEG receiver.After deployment into the aneurysm and before detachment during awake surgery, subjects were presented with a value-based decision-making task for 10 minutes while endovascular WEB recordings were captured and referenced with scalp electrodes.All recordings were completed within the standard 10minute monitoring period to ensure stable WEB positioning, stagnation of contrast inside the aneurysm sac, and adequate flow through the afferent and efferent arteries.Therefore, OR time was not extended for research participation nor was any additional surgical risk introduced to the participants.Results: All patients underwent successful embolization and evEEG recording with no complications.Event-related potentials (ERP) were detected on scalp EEG in 6/15 (40%) patients.Of these 6 patients, low-gamma (30-70Hz) response on WEB channels was captured in 4/6 (75%) cases.In these 4 patients, the WEB device was deployed into the anterior communicating artery, basilar tip, and two middle cerebral artery aneurysms.EKG artifact on WEB channels was present in 11/15 cases. Conclusion:Placement of an implantable WEB device within the cerebral aneurysms of awake subjects is capable of capturing task-specific electrical brain activities.Future studies are warranted to further establish safety, efficacy, and support for evEEG as a potential tool for neural recording, deep brain stimulation, and brain-machine-interface.