Challenges and Opportunities in Combining Ultrasound and Inductive Coupling for Energy Supply and Bidirectional Data Exchange in Bioelectronics Medicine Implant Networks

Personalized medicine meets microimplants. Miniaturized, distributed implants may offer treatment options for diseases in which pharmaceuticals do not work for all patients or do not exist at all. In order to supply these implants efficiently with energy combinations of inductive links and ultrasonic transducers were investigated. This methodological review contributes with a comprehensive overview on the energy supply aspects of neural implants and summarizes basic mechanisms, differences and commonalities with the most widespread method, inductive coupling. It is believed that this review as seminal work can guide researchers who are not familiar with the energy supply field as well as neural engineers, neuroscientists, and clinicians to better understand strengths, weaknesses, threats, and opportunities of this methodology in innovative and novel neurotechnological applications. As figure of merit, inductive links are suggested for short distances and to couple energy into the body, while ultrasound is more efficient over larger lengths and in networks inside the body. The authors suggest planar butterfly coils, membrane‐based piezoelectric micromachined ultrasonic transducers and non‐hermetic encapsulation using silicone rubber for these envisioned neural implant networks.