Ultrasonic imaging in medical diagnosis

The use of ultrasound as an imaging technique for nondestructive visualisation in medical diagnosis has been under development since the late 1940s. In recent years, the resolution of images has improved markedly, and now ultrasound investigations are often the first imaging procedure that a patient encounters in hospital. The mode of operation of current scanners is described in this review, together with the techniques which have enabled improvements in spatial and contrast resolution to be commerically realised.