Ultrasonic image formation: implications for the image processing practitioner

This paper provides an overview of how ultrasound images are acquired and processed in typical commercial equipment, with emphasis on implications for image processing. We begin with a brief discussion of relevant acoustic theory, concentrating on bulk interaction of acoustic waves with tissue. We then discuss different transducer designs and their implications for image quality. Transmit and receive beam formation is discussed, including-the effects of transmit focus, receive focus, and time-multiplex techniques. Typical signal processing techniques used on the beamformed signal are discussed, along with the effect of operator controls. With this system description in hand, we conclude by examining overall clinical image duality. Typical image artifacts, including sidelobes, grating lobes, reverberation, range ambiguity, speckle, shadowing, and dropout are discussed.< >