A Novel Ultrasound Elastography Configuration for Simultaneous Measurement of Contact Forces

The current state of clinical strain ultrasound elastography scanning is marked by the absence of a quantifiable, consistent, and reproducible method for measuring the contact pressure applied by the ultrasound transducer during the scanning process. This gap presents a significant challenge as it restricts the ability to control the factors that might influence imaging outcomes, such as operator variations. On the other hand, quantitative transducer contact pressure measurements implemented in ultrasound strain elastography imaging is a promising solution to reduce the impact of operator variations on imaging outcomes and produce instantaneous quantitative estimations of Young’s modulus. Using miniature pressure sensors with the required accuracy would enable contact pressure measurement in ultrasound strain elastography. An inhomogeneous phantom with multiple layers, each with different mechanical properties, showed an elevated stress magnitude with a decreasing pattern closer to the irregular boundary. Additionally, the surface contact pressure and internal stress distribution studies on phantoms showed good agreement with our finite element method models, with error values of less than 10%. This shows that during breast deformation, the pressure sensor arrays are able to detect initial contact and measure contact pressure. In accordance with the findings and estimated errors from simulation studies and obtained pressure values from pressure sensors, our approach can depict the stress distribution and facilitates assessing the contract pressure during ultrasound strain elastography imaging.