SAN FRANCISCO – Medical electronics researchers showed advances in self-propelled implants and body area networks at the International Solid-State Circuits Conference.
Stanford researchers described two methods for using magnetic fields to propel a millimeter-sized device through fluid at half a centimeter per second. They aim to open up a wide array of new medical applications for tiny remote-controlled implants.
A senior engineer from Toumaz Ltd. described a prototype transceiver that integrates 802.15.6 and Bluetooth Low Energy radios to enable body area networks (BANs). Separately, researchers described a BAN chip that could harvest up to 100 microwatts from the temperature of the human body.
Stanford PhD student Anatoly Yakovlev tapped into the vision of the 1966 movie “Fantastic Voyage,” describing two methods for moving a 0.6mm2 chip wirelessly through a fluid. The techniques assumed a patient would lie on a magnetized bed generating a 0.1 Tesla field while a care provider used a 2W transmitter to control forward motion of a 3x4 millimeter implant.
Yakovlev showed videos of both methods. Researchers showed Stanford medical center physicians who specialize in cardiovascular ablation surgeries a version of the device used to guide a wired catheter.
The current device can only generate forward motion and is too large for use in animal tests. “Looking ahead hopefully sub-millimeter devices are possible, and there are some challenges to solve, but at this stage we just want to demo propulsion,” said Yakovlev.
Medical electronics companies will want a new and smaller prototype suitable for animal testing before they engage with the technology, he said. In parallel, Yakovlev and colleagues hope to design a version with bi-directional links to better monitor and control motion of the device.
The paper and earlier ones on the technology were co-authored with Stanford professor Teresa Meng, a wireless pioneer who co-found Wi-Fi vendor Atheros. Researchers believe the techniques could be used for more precise drug delivery, diagnostics and microsurgery.
A block diagram of Stanford's self-propelled implant chip.