Engineers from the University of California San Diego have developed a new soft wearable skin patch designed to monitor blood flow inside major arteries and veins deep inside the human body. Engineers believe the patch could be worn to provide early warning of strokes and heart attacks. Knowing how fast and how much blood is flowing through the blood vessels inside a person can help clinicians diagnose cardiovascular conditions, including blood clots, heart valve problems, poor circulation in the limbs, or blockages in arteries resulting in strokes and heart attacks.
The ultrasound patch developed by the engineers continuously monitors blood flow along with blood pressure and heart function in real-time. The patch is worn on the neck or chest and can sense and measure cardiovascular signals as deep as 14 centimeters inside the body noninvasively with high accuracy. Engineers say the wearable device can give a more comprehensive and accurate picture of what’s going on in deep tissues and critical organs, including the heart and brain.
Wearable devices engineered to penetrate deep tissue depths, and sense signals beneath the skin provide new insights for healthcare practitioners. The patch also features an ultrasonic beam that can be tilted at different angles and steered into areas of the body not directly under the patch. That capability is a first. Typically wearable sensors are only able to monitor areas directly below them.
With past wearable devices, measuring signals in a different position required the patch to be moved. The new invention can probe areas wider than its footprint opening up additional opportunities for study. The patch is made from a thin sheet of flexible polymer that adheres to the skin. An array of millimeter-sized ultrasound transducers is embedded in the patch.
Each of those transducers is individually controlled by a computer creating an ultrasound phased array. The array operates in two main modes, with one synchronizing all transducers to transmit ultrasound waves together to produce a high-intensity beam focusing on one spot. The other mode allows the transducers to be programmed to transmit out of sync, producing ultrasound beams that can be steered at different angles. The patch still has a long way to go before it’s ready to be used clinically.