A life-saving medical tool is the image of the inside of the human body through the use of a sputum scanner. Researchers have shrunk the handheld probe, which requires a highly trained technician to move over the skin, to a flat chip that is the size of a postage stamp and sticks to the skin. The new device can record high-resolution videos for two days at a stretch, capturing blood vessels and hearts laboring as test subjects gulp juice and then digest it.

A mechanical engineer at the Massachusetts Institute of Technology and co-author of a paper describes a new device that can be applied to the body within 48 hours. Recording still pictures and videos of internal organs during this time could be used to diagnose heart attacks and tumors, test the effectiveness of drugs and assess general heart, lung or muscle health. It can change the paradigm of the field of Wearable Devices.

Access to traditional scans that look beneath the skin is limited. A mechanical engineer at the University of Texas at Austin, who was not involved in the new research, said that the conventional handheld Ultrasonic requires well-trained technicians to put the probe on the skin. It is tedious and very short-term. The scans are expensive and can't be used in tests where the subject is exercising or putting their body under stress. She says that conventional Ultrasonics have limitations. It will open a lot of new possibilities if we can make it easy to wear and use.

Researchers have tried to make stick-on patches. In order to stretch themselves, earlier devices were designed to be stretchable. The form factor could not accommodate the number of transducers that transform electrical power into sound waves that are too high for humans to detect. Waves are sent through a layer of gel into the human body, where they bounce off internal structures and return to the transducer array. The mechanical waves are sent to a computer to be translated into images.

The more transducers, the better the picture. Philip Tan, an electrical engineer and a graduate student at U.T. Austin, was not involved with the new study but co-authored the analysis piece. When the wearer moves, the configuration of transducers shifts and makes it difficult to capture stable images.

Instead of making the device stretchy, the team attached a rigid probe to a flexible layer of glue. A hybrid of a water-rich polymer and a rubberlike material called an elastomer is used to make this glue. It's in a solid state, but it's in a piece of solid material. The water inside the Jell-O will not evaporate out if the surface is covered. The bioadhesive stuck the probe firmly to the skin for 48 hours and provided a cushion to protect the electronics from flexing.

The probe that produced waves at different frequencies penetrated the body to different depths. A high Frequency of 10 megahertz can reach a couple of centimeters beneath the skin. The researchers captured the action of blood vessels and muscles when test subjects moved from sitting to standing. A lower frequencies of three megahertz can be used to get inside the body. The researchers recorded the stomach emptying out as their system processed a couple of cups of juice by using this frequencies. The researchers compared the images gathered with their probe with those captured by a device that can be stretched. The resolution of ours is ten times higher than the stretchable one.

A device that keeps a constant watch over certain parts of the body could be used to diagnose and monitor a variety of ailments. Over time, doctors could watch the growth of a tumor. Someone at high risk of hypertension might wear a patch to measure their blood pressure, and if it goes up or down, they'll know. A COVID patient could stay at home if they needed to go to the hospital due to a lung problem. Detection and diagnosis of heart attacks is perhaps the most important application. Cardiac disease is the leading cause of death in the U.S. Wearable device developers are interested in heart health Smart watches like the Apple Watch can be used to track the electrical signals that indicate heart activity. It is possible to diagnose heart attacks. Studies show that EKG can only diagnose a small percentage of heart attacks. The majority of heart attacks need to be seen by a medical professional. A patient's heart could be scanned continuously to detect their symptoms.

Tan says that the new device opens new types of medical diagnoses that can't be done in a static setting. If you want to assess heart health, it is helpful to measure the organ's activity while exercising, but it is difficult to hold an Ultrasonic wand against a running subject's chest. They were able to show that you can get high-quality images of the heart even during motion with a Wearable Ultrasonic Patch.

The bioadhesive is not ready for use. It needs to be plugged into a computer that can collect and analyze data from the probe. A wire is connected to a data acquisition system. My group is trying to miniaturize and integrate everything into our device. The patch will be upgraded with a wireless data-transmission system and a small power source. Thanks to shrinking electronic components and fabrication methods, Lu and Tan agree that this is a feasible goal. Lu thinks that if the field can attract federal and private investment, it could be possible within five years.

Wearables that monitor human health include existing devices that collect information about heart rate, sleep quality and even stress. Our human body has a lot of personal, highly continuous, distributed and multimodal data about our health, our emotions, our attention, and so on. We are full of data. How can they be reliably and continuously?

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