Engineers at MIT have created an ultrasound patch that can provide long-term ultrasound imaging of internal organs and structures. The device contains a rigid piezoelectric probe array and uses an underlying layer of elastomer-covered hydrogel in lieu of the gel applied to the skin during conventional ultrasound procedures. At just the size of a postage stamp, the ultrasound patch is highly portable and less expensive than conventional ultrasound technologies. The current iteration of the device requires a wired connection to view the images, but the researchers are working to make the device wireless, and report that in the future the technology may be suitable for patients to take home and apply themselves.
At present, ultrasound imaging requires a clinician or technician to apply a messy gel and hold a probe against the skin to obtain images of the underlying organs. This is clearly impractical for long-term imaging, and it also requires expensive equipment and the need to attend a clinic or hospital. To address this, these researchers have created a small wearable patch that can look inside the body for up to 48 hours.
“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,” said Xuanhe Zhao, one of the creators of the new device. “We believe we’ve opened a new era of wearable imaging: With a few patches on your body, you could see your internal organs.”
Previously, researchers have attempted to develop wearable ultrasound technology, with mixed success. “Wearable ultrasound imaging tool would have huge potential in the future of clinical diagnosis,” said Chonghe Wang, another researcher involved in the study. “However, the resolution and imaging duration of existing ultrasound patches is relatively low, and they cannot image deep organs.”
To achieve better ultrasound resolution, the researchers paired rigid transistors with a sticky layer that can easily attach to the user’s skin. This prevents the transistors from shifting position with respect to each other, but maintains appropriate skin contact. The hydrogel layer at the bottom of the patch allows sound waves to propagate through and it is enclosed with an elastomer layer that prevents the gel from drying out.
See a video about the technology below.