If you’ve ever had an ultrasound, it most likely involved going to an office and getting slathered with warm gel before a clinician rubbed a probe over an area of your body. One day, and perhaps one day soon, that same technology may be possible using just a small ultrasound sticker and a smartphone. Researchers at the Massachusetts Institute of Technology (MIT) have created a stamped-sized device that adheres to the skin to provide high-resolution imaging of organs and major blood vessels for up to 48 hours.
How small is it? The entire device measures around 2 square centimeters across, with a thickness of 3 millimeters. The base has a layer of solid hydrogel sandwiched between two thin layers of elastomer, which keep the middle layer from dehydrating. This hydration is important, as researchers say highly hydrated hydrogel is needed for acoustic waves to effectively penetrate and create high-resolution images. And the device has got some serious sticking power; the bottom layer of elastomer sticks to the user’s skin, while the top layer bonds to an array of transducers.
How do we know it works? The team at MIT conducted a test with volunteers who wore the stickers on body parts including the arm, abdomen, chest, and neck. Researchers say the patches provided clear images for up to 48 hours and held up to real-life activities including biking, jogging, and weightlifting… all of which were performed by the volunteers at a lab. These activities offered insight into the device’s functionality. For example, the stickers were able to measure a change in the heart’s shape during exercise, stomach distension caused by drinking liquid, and signs of micro-damage to muscles while lifting weights.
As is the case with bulky ultrasound equipment, the new device works by turning reflected sound waves into digital images. At this point, the stickers are also similarly hard-wired to imaging instruments. But the researchers are working on a way to make this data transfer wireless, thus turning the device into a true wearable that could be offered by healthcare providers or even sold over the counter at pharmacies. MIT professor Xuanhe Zhao says, “We imagine we could have a box of stickers, each designed to image a different location of the body…and the patches would communicate with your cell phone.”