Eigenspace Beamformer Combined with Generalized Sidelobe Canceler and Filters for Generating Plane Wave Ultrasound Images

Abstract

The use of plane waves allows images with higher frame rates compared to conventional modes. Some studies have shown that the use of the Eigenspace Beamformer technique associated with the Generalized Sidelobe Canceler (EBGSC) reduces the effects of interference and noise, minimizing sidelobes and providing images with higher contrast and resolution compared to the Delay and Sum (DAS) and the Minimum Variance (MV) methods. Filters can also be applied after image processing to reduce speckle signals present in ultrasound images such as the Wiener and Kuan filter. This work presents the implementation of the EBGSC method with Wiener and Kuan filters to improve the processing of plane wave ultrasound images. The EBGSC method combined with Wiener filter (EBGSC-W) showed an improvement in the contrast of 70% and 57.2% when compared to the DAS and GSC methods, respectively. The geometric distortion was evaluated using the parameter of the full width at half maximum (FWHM) and the EBGSC-W also obtained a reduction in lateral FWHM by 63% and 25% compared to the DAS and GSC methods, respectively, approaching to the actual value of the target size (0.1 mm). The EBGSC method with the Kuan filter (EBGSC-K) showed improvements in the lateral FWHM, however, it worsened the contrast, with loss of information.