EVANSTON, IL — Imagine a device that could be placed inside the body and manage pain by targeting the source directly. Biomedical engineers looking for an alternative to highly addictive opioids have created a soft, flexible implant that can manage pain by wrapping around nerves and cooling them at the site.
It's a tiny implantable electrical device that dissolves inside your body after it's done with its work.
"The device specifically is designed to cool or reduce the temperature of certain targeted peripheral nerves that are carrying pain signals up to the brain from a part of the body that's injured," said John Rogers, a professor of materials science, biomedical engineering and neurological surgery at Northwestern University who led the development of the device.
"It can be very precisely targeted, and moreover it can be turned on and off," said Rogers.
The biocompatible, water-soluble device is about the size of a rubber band and would be softly wrapped around the affected nerves at the tail end of surgery.
Embedded in the device are tiny channels the size of a human hair.
"Through those channels, we can pump a coolant," said Rogers.
That liquid coolant inside is evaporated at the specific location of a sensory nerve.
Just like going outdoors in the cold can numb your fingers, the device delivers cooling to the nerves deep within the body, numbing them and blocking pain signals to the brain.
"You don't want to cool the nerve too much, you freeze it, and then you do irreparable damage to the nerve. But it has to be cool enough to achieve that blocking effect," Rogers said.
There's also a dial that can control the magnitude of the cooling; it's very different from a medication that spreads throughout the body.
"They wash throughout the entire body, the regions of the body where they're not needed and where they can potentially cause harm," Rogers said.
Once the pain management is complete, the device just melts away.
It was tested in small animals with the goal of eventually making it for humans.
"The next step would be to move to larger animal models, non-human primates, ultimately before moving into first in man human studies," Rogers said.
If all goes well, health care providers could find this non-pharmaceutical solution in their pain management toolkit within a few years.