Wireless endovascular nerve stimulation with a millimeter-sized magnetoelectric implant

Abstract

Implanted bioelectronic devices have the potential to treat disorders that are resistant to traditional pharmacological therapies; however, reaching many therapeutic nerve targets requires invasive surgeries and implantation of centimeter-sized devices. Here we show that it is possible to stimulate peripheral nerves from within blood vessels using a millimeter-sized wireless implant. By directing the stimulating leads through the blood vessels we can target specific nerves that are difficult to reach with traditional surgeries. Furthermore, we demonstrate this endovascular nerve stimulation (EVNS) with a millimeter sized wireless stimulator that can be delivered minimally invasively through a percutaneous catheter which would significantly lower the barrier to entry for neuromodulatory treatment approaches because of the reduced risk. This miniaturization is achieved by using magnetoelectric materials to efficiently deliver data and power through tissue to a digitally-programmable 0.8 mm2 CMOS system-on-a-chip. As a proof-of-principle we show wireless stimulation of peripheral nerve targets both directly and from within the blood vessels in rodent and porcine models. The wireless EVNS concept described here provides a path toward minimally invasive bioelectronics where mm-sized implants combined with endovascular stimulation enable access to a number of nerve targets without open surgery or implantation of battery-powered pulse generators.

Ultra-flexible endovascular probes for brain recording through micron-scale vasculature

“…First, as MEV implantation induces minimal immune response, future efforts will be directed toward developing stretchable MEV probes with chronic recording capabilities. Second, the platform could be scaled to hundreds to thousands of electrodes for high-density recording and stimulation (16,45) by adapting highly scalable I/O interfaces (46). Third, steering compartments, such as magnetic actuators (18,47), could be incorporated to the tip of the probe to control navigation and improve the branch selectivity.…”

Self-rectifying magnetoelectric metamaterials enable precisely timed remote neural stimulation and restoration of sensory motor functions

“…As a result, ME materials have only enabled remote neural stimulation when they are driven off resonance where the weak ME coupling leads to a seconds-long latency in the neural response or requires extremely high applied magnetic field strengths to reduce the latency to a few hundred milliseconds (14,15). Precisely timed neural stimulation with millisecond latencies has only been achieved using ME materials when they are combined with electronic circuits that convert the high-frequency ME response to a low-frequency electrical stimulus (16)(17)(18)(19).…”