Australian scientists have made a breakthrough in ultrasound technology that could greatly improve the performance of ultrasound imaging.
Ultrasound is a non-invasive technique used to capture internal images of the body such as blood vessels, muscles, organs, and soft tissues. It helps doctors and health professionals diagnose patients’ abnormalities or signs of disease. Unlike other scanning techniques such as X-rays and CT scans, ultrasound does not use ionizing radiation. Instead, it relies on high-frequency sound waves in the range of millions of cycles per second that the human ear cannot hear them.
Ultrasound technology continues to evolve
Conventional ultrasound usually displays images in thin and flat sections of the body. Advancements in ultrasound imaging technology offer great promise for near real-time 3D visualization. Ultrasound continues to evolve additional functions, including 4D ultrasound imaging, elastography, and contrast-enhanced ultrasound using microbubbles. However, there are also significant challenges associated with acoustic sensitivity at higher frequencies and with smaller sensing areas.
The first ultrasound-on-chip shows super-high sensitivity
In a recent study published in Nature Communications, a group of scientists from the ARC Centre for Engineered Quantum Systems, The University of Queensland, successfully utilized the modern nanofabrication and nanophotonic technologies to build the first ultraprecise ultrasound sensing device on a thin chip.
Using dual optical and mechanical resonances within a cavity optomechanical ultrasound sensing system, the ultrasound-on-chip can obtain strong signals with low background noises at kilohertz to megahertz frequencies. More surprisingly, the device was able to detect the miniscule random forces from atmospheric air molecules. Its sensitivity far exceeds other similar sensors such as optical resonance sensors and air-coupled ultrasound sensors.
This groundbreaking research not only finds applications in biomedical imaging, but also benefits to many other acoustic sensing areas ranging from autonomous navigation, trace gas sensing, and scientific exploration of metabolism induced-vibrations of single cells. To further improve the broadband sensitivity, more studies on the sensitivity in different frequency windows are required.
Written by Man-tik Choy, Ph.D.
Reference: Basiri-Esfahani, S. et al. Precision ultrasound sensing on a chip. Nature Communications, 2019;10:132. DOI: 10.1038/s41467-018-08038-4.