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Ultrasound scan

Find out about the different types of ultrasound scans used for cancer tests.

Ultrasound scans use high frequency sound waves to build up a picture of the inside of the body.

The sound waves bounce off the organs inside your body, and the microphone picks them up. The microphone links to a computer that turns the sound waves into a picture on the screen.

Ultrasound scans are completely painless. They are usually done in the hospital x-ray department by a sonographer. 

Why you might have this test

Ultrasound scans can help doctors diagnose a number of different types of cancer.

Preparing for your scan

Check your appointment letter for any instructions about how to prepare for your scan.

You might need to stop eating for 6 hours beforehand. Let the scan team know if this will be a problem for any reason, for example if you are diabetic.

Your team might ask you to drink plenty before your scan so that you have a comfortably full bladder.

Take your medicines as normal unless your doctor tells you otherwise.

What happens

Before the scan

When you arrive you might be shown to a cubicle and asked to take off your outer clothing down to your underwear and put on a hospital gown. Whether you have to undress or not will depend on the part of your body to be scanned. 

During the scan

You go into the scanning room and lie on the couch next to the ultrasound machine. You might be able to sit up depending on which part of your body is being scanned. A clear gel will be spread onto your skin over the scanning site. This helps to transmit the sound waves to the microphone.

You might feel a little pressure as the sonographer presses the microphone against your skin and moves it back and forth over the part of your body being scanned. The scan appears on the screen, which will be next to you. 

Ultrasounds take from 5 minutes to about half an hour, depending on the scan. 

Diagram showing an ultrasound scan

What happens afterwards

You can eat and drink normally after the test. You can go straight home or back to work afterwards.

Internal ultrasound scans

Sometimes, doctors need to put the ultrasound microphone inside your body to get a clearer picture. Most often this is done for a scan of your prostate or vagina.

Rectal ultrasound

You have a rectal ultrasound if you are having your prostate gland examined. This is called a transrectal ultrasound or TRUS. You need to make sure you have had a bowel movement beforehand so your rectum is empty when you come for your appointment. 

A small ultrasound microphone or probe is put into your back passage to get a clearer picture of the prostate. This is uncomfortable, but shouldn't hurt. This scan does not take long.

Vaginal ultrasound

This is sometimes used to look at the ovaries, womb and surrounding structures. It is called transvaginal ultrasound or TVS. 

The doctor or sonographer will ask you to lie on your back with your knees bent and legs apart (as if you were having a cervical screening test or an internal examination). They will keep you covered with a sheet. If this position is difficult for you, you may be able to lie on your side with your knees drawn up to your chest. 

The doctor puts a small ultrasound microphone or probe into your vagina so that the ovaries and womb can be seen on the scan. This may be uncomfortable, but shouldn't hurt. This type of scan does not take long.

Endoscopic ultrasound

This is a combination of having an endoscopy and an ultrasound. 

An endoscope is a long flexible tube with a light and camera attached. Doctors usually use it to look at the inside of your digestive system. The endoscope can also have an ultrasound probe at the tip. This gives doctors more detailed information. 

Doctors use endoscopic ultrasound to look at:

  • the wall of the oesophagus (food pipe)
  • the wall of the stomach
  • part of the small bowel (duodenum)
  • the gallbladder and bile ducts

This test can also look at the lymph nodes in your chest and abdomen.

Possible risks

Ultrasound is a very safe procedure. There are usually no side effects.

Getting your results

Waiting for test results can be a very worrying time. You can contact your specialist nurse if you are finding it hard to cope. You can also get in touch with them to ask for information if you need to. It can also help to talk to a close friend or relative about how you feel.

For support and information, you can call the Cancer Research UK nurses on freephone 0808 800 4040. The lines are open from 9am to 5pm, Monday to Friday.

More information

We have more information on tests, treatment and support if you have been diagnosed with cancer.

Last reviewed: 
13 May 2015
  • The Royal Marsden Manual of Clinical Nursing Procedures, 9th edition
    L Dougherty and S Lister (Editors)
    Wiley-Blackwell, 2015

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