Contrast-enhanced ultrasound imaging of displaced humeral fractures: Results of a pragmatic single-centre study

D Cadoux-Hudson, M Thomas and J Hurst et al

University Hospital Southampton NHS trust

Microbubbles have been available in ultrasonography for Contrast Enhanced Ultrasound (CEUS) for several decades. As the understanding of their properties has improved, so has their use in a therapeutic setting, such as a method for determining the cause of a non-union. Their behaviour in acute bone fractures, or their potential for therapeutic and diagnostic use here is unknown. This study aims to determine the ability of microbubbles to perfuse acute fractures in patients.

Patients with a humeral shaft fracture in our unit were recruited to undergo CEUS of their fracture within 28 days using SonoVue microbubbles. B-mode images were captured with time-intensity curves to assess for perfusion.

Ten patients were recruited, 7 underwent CEUS at a mean of 16 days. The average Peak Intensity (PI) was 1.95×10-6 acoustic units (AU), Area Under the Curve (AuC) 4.68×10-6 , and Time to Peak (TtP) 23.4 seconds. There was a reduction in AuC and PI with increased time from injury, (5 versus 28 days; PI, -70.8%, AuC -62.4% and TtP -20.3%). There were detectable microbubbles within the fracture site, demonstrating microbubble contrast within the fracture site outlined.

This preliminary human clinical study demonstrates the presence of peripherally injected microbubbles in acute fractures for the first time. This demonstrates the viability of using microbubbles for therapeutic purposes and for assessing changes in blood flow through fractures over time from acute injury in clinical settings.