Medical information for patients

Ultrasound scanning

Ultrasound scanning (ultrasonography) is a quick, easy, and relatively safe investigation which helps us in many areas of medicine.


Ultrasound scanning (ultrasonography) is usually performed in the hospital, by a doctor or a radiographer.

The scan works rather like sonar does in detecting submarines under the water. A device rather like a microphone is pressed against the area being scanned, often using some jelly to improve the contact. This device sends out very high frequency sound waves which go into area being examined, and bounce back when they hit an organ (like an echo bounces back when you shout across a valley).

This is all processed by a computer, which produces a map of the area being scanned, like on a radar screen.

The technique allows us to see static structures, but also to observe moving parts, eg the heart of a baby in the womb, or the valves inside an adult heart.

Most scans are done from outside the body, through the skin, but some are done internally, using special probes eg in the oesophagus to give improved views of the heart, or in the vagina to better show up the womb, pelvic organs and pelvic floor.

Ultrasound scanning (ultrasonography) is used to examine many parts of the body, and can give us great detail, but there are conditions and organs to which it is well suited, and others which need different techniques in order to investigate them.

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