Ultrasound

This chapter discusses the basic physics and properties of sound waves. Ultrasound is defined, and the behaviour of ultrasound in biological tissues, including reflection, interference, acoustic impedance and attenuation is discussed. The piezoelectric effect and physics of ultrasound crystals as well as transducer shape and design are considered. Clinical characteristics of single and multiple-array transducers are discussed, as well as key concepts such as image resolution, image modes and image artefacts. The chapter concludes with a discussion of the physics and clinical applications of Doppler ultrasound including spectral array, colour and power Doppler.