Ultrasound Image
A group of MIT engineers have developed an adhesive patch, roughly the size of a stamp, that conforms to the movements of the wearer while providing high-resolution internal images for up to 48 hours. Credit: Felice Frankel

Though medical ultrasound imaging technology has been in use since the mid-20th century, ultrasound technology capable of imaging patients over a longer term have been out of reach. Robotic arms with a probe that holds in place a transducer face issues with ultrasound gel depletion that interrupts imaging, and efforts to create stretchable ultrasound probes that conform to a patient’s body have produced distorted, low-resolution images.

Recently, a group of engineers at MIT, however, have created an adhesive patch roughly the size of a stamp (approximately 2 sq. cm) capable of producing high-resolution, continuous ultrasound imaging for up to 48 hours. The ultrasound “sticker” pairs an inflexible arrangement of transducers with a stretchy adhesive layer, which allows the device to stay in place—to provide precise images—while moving with the wearer.

The device avoids the common issue of traditional ultrasound gel depletion by using the team’s special hydrogel, which itself is elastic and encapsulated between two layers of adhesive elastomer. The hydrogel is made primarily of water and easily transmits the sound waves necessary for proper imaging.

Volunteers were able to wear the ultrasound sticker while performing a variety of activities, including jogging, biking, lifting weights, drinking, and urinating, and with each activity, the researchers were able to see the corresponding changes of deep organs and blood vessels.

While the researchers are working to make the stickers wireless, for now, they must be connected during use. Even in their current, wired form, the wearable technology has exciting implications, with hospitals soon able to image patients throughout their stay with no ultrasound technician needed.

If the team can create a wireless version of the device, the implications for the medical industry are huge. The researchers predict wearable imaging stickers one could be prescribed by a doctor or buy over the counter for at-home imaging of organs, as well as tumor progression and fetus development.

“We envision a few patches adhered to different locations on the body, and the patches would communicate with your cellphone, where AI algorithms would analyze the images on demand,” says Xuanhe Zhao, the study’s senior author. To that end, the team also is developing AI software algorithms to better interpret and diagnose the images sent back by the devices. “We believe we’ve opened a new era of wearable imaging: With a few patches on your body, you could see your internal organs.”