Spatial-angular compounding for elastography using beam steering on linear array transducers.

Spatial-angular compounding is a new technique that enables the reduction of noise artifacts in ultrasound elastography. Under this method, compounded elastograms are obtained from a spatially weighted average of local strain estimated from radio frequency (rf) echo signals acquired at different insonification angles. In previous work, the acquisition of the rf signals was performed through the lateral translation of a phased-array transducer. Clinical applications of angular compounding would, however, require the utilization of beam steering on linear-array transducers to obtain angular data sets, which is more efficient than translating phased-array transducers. In this article, we investigate the performance of angular compounding for elastography by using beam steering on a linear-array transducer. Quantitative experimental results demonstrate that spatial angular compounding provides significant improvement in both the elastographic signal-to-noise ratio and the contrast-to-noise ratio. For the linear array transducer used in this study, the optimum angular increment is around 1.5 degrees-3.75 degrees, and the maximum angle that can be used in angular compounding should not exceed 10 degrees.