Ultrasound is now widely used in human medicine, particularly for monitoring the development of babies in the womb.
Principles of ultrasound
Ultrasound is rather like small-scale radar. Pulses of very high frequency sound waves are emitted from a probe, directed into the tissues being examined. The sound waves are reflected in different proportions whenever tissues of different density join. The probe collects the reflected sound waves, and the computer analyses them and is able to tell from how deep in the tissue they have been reflected. This information, combined with the amount of reflected waves, is built up into a cross-sectional picture of the body at that point.
How we use ultrasound
We have a powerful ultrasound unit which is used for a variety of purposes, among them pregnancy diagnosis, investigation of bladder problems and heart disease.
Ultrasound examinations give different information from radiographic examinations, and so both may be used on the same patient.
It is not quite so important to have a still patient for ultrasound examinations (compared to X-rays) so we can often do them on fully conscious patients.