An electronic implant that monitors brain injuries before dissolving and being reabsorbed by the body has been developed by researchers at the University of Illinois.
After a traumatic brain injury or brain surgery, doctors need to monitor the patient for swelling and pressure in the skull to ensure no adverse side-effects occur.
Current monitoring technology is bulky and invasive, with wires restricting a patient's movements and which hamper physical therapy as they recover.
Such implants also carry the risk of allergic reactions, infection and haemorrhage because they are required to be continuously hardwired into the brain.
The newly developed sensors are smaller than a grain of rice and are built on extremely thin sheets of silicon, which is naturally biodegradable.
They are designed to function normally for a few weeks and then dissolve away into the body's own fluids.
"This is a new class of electronic biomedical implants," said professor John Rogers who is directing the research. "These kinds of systems have potential across a range of clinical practices, where therapeutic or monitoring devices are implanted or ingested, perform a sophisticated function, and then reabsorb harmlessly into the body after their function is no longer necessary."
The team has already implanted prototype sensors into the heads of rats to test for performance and biocompatibility. They found that the temperature and pressure readings from the dissolvable sensors matched conventional monitoring devices for accuracy.
They connected to a wireless transmitter roughly the size of a postage stamp, which is implanted under the skin but on top of the skull.
"The ultimate strategy is to have a device that you can place in the brain - or in other organs in the body - that is entirely implanted, intimately connected with the organ you want to monitor and can transmit signals wirelessly to provide information on the health of that organ, allowing doctors to intervene if necessary to prevent bigger problems," said neurosurgeon Rory Murphy who co-authored a paper on the new implants.