Discovery paves way for safe, wirelessly charged implants

1 min read

Implantable electronic devices have been around for a while now, but their use has been somewhat restricted due to the bulky batteries required to power them.

Now, a team from Stanford University has found a way to wirelessly transfer energy to tiny medical devices implanted inside the human body. The breakthrough, they believe, could pave the way for new electroceutical devices that allow physicians to treat diseases with electronics rather than drugs. The crux of the discovery involves a new way to control electromagnetic waves (far field and near field) inside the body. Far field waves can travel long distances, but interact weekly with the human body. Near field waves, on the other hand, can only transfer power over very short distances and are severely refracted when they encounter human tissue. Led by assistant professor Ada Poon, the Stanford team was able to combine the best of the two worlds by developing a power source that generates a near-field wave that is harmless to humans and is also able to effectively penetrate tissue to charge small electronic implants inside a patient. The new method, described as mid-field wireless transfer, has been tested by an independent laboratory and fell well below the danger exposure levels for human safety. The charging system has also been tested in a pig and used to power a tiny pacemaker in a rabbit. The researchers are currently preparing the system for human testing, although they say this could be a few years off.