Detail. Ultrasound scanners work by pasing ultrasonic waves into the body which bounce back like echoes when they meet different kinds of tisue. The scanner picks up these reflected sound waves and displays them on a screen, creating an image of the foetus. This scanner, made by Nuclear Enterprises Ltd in Edinburgh, Scotland, was used by Dr Stuart Campbell in his cephalometric researches into foetal development. It is capable of carrying out both A and B scans, which can provide different displays of internal structures such as the foetus. Campbell's work has established many of the procedures which have made ultrasound a key part of antenatal care, offering a safe way of checking the development of the foetus.
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