OBJECTIVE:Quasi-static ultrasound elastography is a technique for measuring tissue deformation (strain) under externally applied loading and can be used to identify the presence of abnormalities. The objective of this study was to demonstrate the efficacy of averaging strain images from repeated compression cycles in mitigating user-induced error using quasi-static ultrasound elastography.METHODS:Freehand compressions were performed with an ultrasound transducer on the biceps brachii of nine participants (five males and four females), as well as with a custom automated compression system. Sets of strain images from the freehand techniques were averaged to create single representative images and compared against strain images from the automated compressions using both qualitative and quantitative metrics.RESULTS:Significant improvements in intra-operator repeatability and interoperator reproducibility can be achieved by averaging strain images from four to eight repeated compressions. The resulting strain images did not lose significant image data compared with strain images from single automated compressions.CONCLUSION:Averaging is introduced as a feasible and appropriate technique to improve strain image quality without sacrificing important image data.
Matthew Leineweber, J Westborn, A Cochran, Y Gao, and J Choi. "Averaging improves strain images of the biceps brachii using quasi-static ultrasound elastography" British Journal of Radiology (2014). doi:10.1259/bjr.20130624