The Imaging Properties Of Ultrasonic Pulse-Echo Visualisation Systems

The technique of ultrasonic pulse-echo visualisation for medical diagnosis is well known and has received widespread acceptance in clinical practice in many diagnostic areas. The main areas of application at present are the abdominal organs (Ref.l,2), pregnant uterus (Ref.3) and heart (Ref.4). Clinical evaluation studies are being carried out in the eye (Ref.5,6), thyroid (Ref.7), brain (Ref.8) and breast (Ref.9). As the instrumentation and resultant echogram quality have been improved, the range of regions and conditions in which the technique has found application have been greatly increased. It is the aim of this paper to review the assumptions and physical laws upon which the technique is based and to examine the relationship between the limitations set by these considerations and the performance obtained with present equipment.