Sound Speed Fluctuations in Medical Ultrasound Imaging Comparison between Different Correction Algorithms

A current trend in diagnostic ultrasound is the use of high imaging frequencies and large apertures yielding an increased image quality and lesion detectability. However, in many applications, sound speed inhomogeneities induce phase aberra­tions that limit the expected resolution of these sytems. For example, the speed of sound in abdominal fat is about 1460 m/s while it is about 1560 m/s in liver and kid­ney. Moreover, the phase aberration pattern varies from patient to patient, and main­ly depends on the fatty content of their abdominal wall. Therefore, one challenge of modern echography is to provide the best possible image quality and lesion detectabi­lity across a population of patients. This requires the ability to, in vivo and in real time, measure and correct the phase aberrations.