Performance evaluation of combined spatial compounding-adaptive imaging: simulation, phantom and clinical trials

Spatial compounding reduces speckle and increases image contrast by incoherently averaging images acquired at different viewing angles. Adaptive imaging improves contrast and resolution by compensating for tissue induced phase errors. Aberrator strength and spatial frequency content markedly impact the desirable operating characteristics and performance of these methods for improving image quality. We present simulation, phantom and clinical experiments of spatial compounding, adaptive imaging, and a combination of these two methods in contrast and resolution tasks. With aberrations at high strength and low spatial frequency content, spatial compounding can yield significant (20%-50%) improvements in contrast-to-noise ratio (CNR). For all aberration strength and spatial frequencies, adaptive imaging yields superior improvement to spatial compounding in restoring lateral spatial frequencies of the image. Concurrent use of both imaging techniques yields the best results in CNR and resolution.