Clipping removal in Synthetic Aperture Imaging

Clipping artifacts impact the image quality and diagnostic accuracy in ultrasound imaging. This study introduces a post-processing technique designed to eliminate clipping in ultrasound scans acquired using synthetic aperture ultrasound systems (SAUS). It is hypothesized that the proposed method can effectively masks out clipped signals while preserving non-clipped contributions and without a significant loss of image quality. A phantom and an in-vivo rat brain scan were used to test this hypothesis. The analysis of the phantom data showed that the proposed method can be applied to remove mild levels of clipping without a significant loss in contrast and resolution. In fact, when up to 30% of the data was clipped, the loss in resolution after applying clipping removal was lower than 2.5% and the contrast decreased less than 7.9%, when compared with the original non-clipped image. In-vivo results, on the other hand, demonstrated that applying the proposed algorithm effectively removes clipping artifacts while preserving the underlying information. Additionally, it enhances the image's dynamic range by approximately 12%, when compared with the clipped data.