An ultrasound scan uses high-frequency sound waves to create an image of a part of the inside of your body.
What is it used for?
It is used to diagnose problems in many parts of your body such your liver, heart, kidneys, ovaries and testes. It can also be used as a guide during some types of biopsy so your doctor can see exactly where they are placing the biopsy needle.
Do I need to prepare?
Sometimes you have to prepare, such as drinking water and not going to toilet, or not eating for several hours beforehand.
A member of the team providing your care will explain what to do if you do need to prepare.
What happens during the procedure?
An ultrasound scan is safe and painless. You are usually awake and normally takes between 15 and 45 minutes.
There are three main types, depending on which part of the body is being scanned and why:
- external ultrasound, where a small handheld device called a transducer is placed on your skin, and moved over the part of the body being examined.
- internal ultrasound, where an ultrasound probe is put into your vagina or rectum. This may be a bit uncomfortable but does not usually cause any pain.
- endoscopic ultrasound (EUS), a type of endoscopy. You may have a sedative or a general anaesthetic for this type of ultrasound.
NHS Choices explains more about ultrasound scans.