Minimally invasive endovascular stent-electrode array for high-fidelity, chronic recordings of cortical neural activity

Abstract

High-fidelity intracranial electrode arrays for recording and stimulating brain activity have facilitated major advances in the treatment of neurological conditions over the past decade. Traditional arrays require direct implantation into the brain via open craniotomy, which can lead to inflammatory tissue responses, necessitating development of minimally invasive approaches that avoid brain trauma. Here we demonstrate the feasibility of chronically recording brain activity from within a vein using a passive stent-electrode recording array (stentrode). We achieved implantation into a superficial cortical vein overlying the motor cortex via catheter angiography and demonstrate neural recordings in freely moving sheep for up to 190 d. Spectral content and bandwidth of vascular electrocorticography were comparable to those of recordings from epidural surface arrays. Venous internal lumen patency was maintained for the duration of implantation. Stentrodes may have wide ranging applications as a neural interface for treatment of a range of neurological conditions.

Blending Electronics with the Human Body: A Pathway toward a Cybernetic Future

“…The keys for successful and noninvasive integration of such stents within the delicate capillaries of the brain are high flexibility and good biocompatibility. To this end, flexible and ultrathin electronic stents represent viable treatment options that can maintain the blood flow into the brain tissue without causing significant damage to the surrounding tissue while at the same time enabling neural recordings 389, 391. For instance, Oxley and co‐workers391 recently developed an electronic stent that could integrate with the ultranarrow capillaries of the brain for both brain activity recordings and neural stimulation ( Figure 11 ).…”

“…To this end, flexible and ultrathin electronic stents represent viable treatment options that can maintain the blood flow into the brain tissue without causing significant damage to the surrounding tissue while at the same time enabling neural recordings 389, 391. For instance, Oxley and co‐workers391 recently developed an electronic stent that could integrate with the ultranarrow capillaries of the brain for both brain activity recordings and neural stimulation ( Figure 11 ). In simple terms, this electronic stent was made from a self‐expanding and commercially available stent coated with biocompatible Pt electrodes for recording purposes and was coined the “stentrode”.…”

“…In simple terms, this electronic stent was made from a self‐expanding and commercially available stent coated with biocompatible Pt electrodes for recording purposes and was coined the “stentrode”. The stentrode could readily be integrated within the curved blood vessels of the sheep brain for high‐fidelity recording of somatosensory evoked potentials (SSEPs) in close proximity of the superior sagittal sinus 391. This type of electronic stents has also provided a new avenue for deep brain stimulation for up to 190 days with minimal trauma inflicted to the brain 388, 391.…”

“…The stentrode could readily be integrated within the curved blood vessels of the sheep brain for high‐fidelity recording of somatosensory evoked potentials (SSEPs) in close proximity of the superior sagittal sinus 391. This type of electronic stents has also provided a new avenue for deep brain stimulation for up to 190 days with minimal trauma inflicted to the brain 388, 391. Such implantable systems are indeed safe and can be delivered via conventional catheter angiography and therefore present a minimally invasive option compared with traditional open‐brain surgery.…”

“…h) A 3D representation of an implanted stentrode and its corresponding peak‐to‐peak amplitude recording. Adapted with permission 391. Copyright 2016, Macmillan Publishers Ltd.…”