Contrast-Enhanced Ultrasound

The recent decade has witnessed the great improvement of contrast-enhanced ultrasound (CEUS) and its extensive use in clinical practice, which is undoubtedly the major breakthrough in the field of diagnostic ultrasound in recent years. The concept of CEUS can be looked back to 60s in the last century, whereas only in 2000s CEUS regained increasing attention in both clinical practice and basic research. The current popularization of CEUS is largely due to the emergence of low acoustic power contrast-specific imaging mode and microbubble-based contrast agent filled with inert gas. After administration of ultrasound contrast agent intravenously, the low acoustic power contrast-specific imaging mode facilitates visualization of the nonlinear signals from the microbubbles in the circulation and suppresses the linear signals from the surrounding tissues, which leads to an improved signal-to-noise ratio and facilitates depiction of macro- and microcirculation of the region of interest (ROI) noninvasively. The low acoustic power also limits the damage to the microbubbles under acoustic push; thus, more microbubbles will remain in the circulation and a long time CEUS depiction is available [1].