Implementation of Wide-Beam Ultrasound Imaging Based on a Convex Transducer
Ultrasound wide-beam imaging is a high frame rate ultrasound imaging method that can better balance several important imaging properties such as image spatial resolution,contrast ratio,and frame rate,which is implemented by putting the transmitting focus point far away from the actual imaging depth when compared to the traditional line-by-line scanning,plane and diverging wave imaging methods.Current studies on ultrasound wide-beam imaging are only based on linear array ultrasound transducers that have a limited imaging field of view and are not suitable for imaging of deep tissues and organs.In this paper,we investigated the wide-beam imaging algorithm based on a convex array ultrasound transducer and evaluated performance of the wide-beam imaging method with convex linear array.With a convex array transducer with 128 arrays,wide-beam imaging was implemented in two environments,a simulation platform and a real experiment scenario.The original channel data were first collected in both scenarios and then a delay and sum method was used to beamform and reconstruct the wide-beam ultrasound images.Quantitative analysis was performed in terms of the image contrast and spatial resolution and compared with the traditional focused line-by-line scanning,the diverging wave imaging methods.Compared with compound diverging wave imaging,the wide-beam imaging had higher image contrast(simulated case:19.6 dB,increased by 67.1%;experimental case:19.1 dB,increased by 33.1%),but its performance on resolution was different in the simulated and experimental cases(spatial resolution in the simulated case:1.11 mm,increased by 18.1%;in the experimental case:1.48 mm,decreased by 15.4%).Overall,the wide-beam imaging had better performance than compound diverging wave imaging.In comparison with the focused line-by-line scanning,wide beam imaging exhibited more uniform imaging resolution and a higher frame rate.This study implemented the wide-beam ultrasound imaging based on a convex imaging transducer for the first time and validated that the imaging method had more balanced imaging performance than the diverging wave imaging methods and traditional focused method,which offered a better imaging strategy for some relevant clinical applications,especially for the abdominal ultrasound.
medical ultrasound imagingbeamformingwide-beam imagingabdominal ultrasound