Contrast enhanced ultrasound

Your doctor has requested that you undergo an ultrasound examination with contrast. This examination is usually performed to provide more information about a lesion or blood flow in part of your body.

The procedure involves using an ultrasound machine to view images of the inside of your body. Contrast enhanced ultrasound is like a regular ultrasound, with the addition of the use of small, gas filled bubbles, that are slightly smaller than a cell in the blood. These “microbubbles” are non-toxic and help us to see cavities in the body, large vessels and blood flow to organs. The microbubbles dissolve rapidly and harmlessly in your blood stream.

This type of procedures is safe and easy to perform with no radiation and no risk to the kidneys.

There is a very low risk of minor side effects, including:

• Headache (less than 5%).
• Nausea (0.5%).
• Feeling hot (0.3%).
• Injection site pain (0.3%).

These side effects should settle on the same day as your scan. 

Rarely there have been reactions to the contrast with certain heart diseases such as shunts. We will check your allergies before the procedure to minimise this risk. The doctor may give you medicine if you do have an allergy and we will monitor you after the procedure. 

The only severe side effects have occurred in patients with pulmonary hypertension or serious heart and lungs conditions. You should let us know if you have a severe heart condition, are pregnant or have had a severe allergic reaction in the past.

No special preparation is needed in most cases. However, if you need to starve or fill your bladder, we will inform you of this on your appointment letter.

Yes, you may bring a friend or relative with you. It may not always be possible for them to accompany you into the scanning room but if it is necessary, please do ask and we will try to accommodate your request.

Please go to the Gate 18 reception desk and follow the check-in process in your appointment letter. You will be shown where to wait until a member of staff comes to collect you.

You will be seen by a radiologist (a doctor who specialises in X-rays) or a sonographer (a radiographer who specialises in ultrasound). 

North Bristol NHS Trust is a teaching hospital; there may be a trainee present for some examinations. They will be introduced at the beginning of the examination. If you would prefer them not to be present, please feel free to say to the radiologist or sonographer.

We will tell you if you need to remove any clothes covering the area being examined before your examination. Private cubicles are available if you need to take off your outer garments or put on a hospital gown.

• A member of the team will place an intravenous (IV) catheter for microbubble contrast in one of your arm veins before the scan. A small plastic tube (cannula) may be put into a vein in your arm to allow us to administer during the procedure.
• After this, we will dim the lights so that the images on the screen can be seen more clearly.
• You may be asked to take deep breaths and to hold your breath for a few moments.
• The radiologist or sonographer will move the ultrasound probe over your skin while viewing the images on a screen.
• Ultrasound images will be taken before and after the injection, so that they can be viewed later.
• Occasionally a patient might experience a bitter taste in the mouth or burning or cold sensation in the arm after the injection. The cold sensation is usually the result of the saline (salted water) used to flush the cannula, not the contrast itself.
• After the scan we might ask you to stay in the department for 10-20 minutes to ensure you are well before you leave the department. Before you leave, a member of the team will remove the cannula.

The contrast agent used with ultrasound is approved for use in the UK, Europe and North America.

In the UK, it has been approved for use in the heart and liver lesions. We would like to make you aware however, that it is not specifically approved for examinations of the other organs. This may seem unusual as we will be injecting the same material in the same amount that would be used to examine your heart and liver but scanning over your kidney or other organs. This is known as an “off label use of an approved drug” and is a common practice since often drugs are not specifically approved for every possible use. 

Should you have further questions please feel free to ask the radiologist who, along with the experienced sonographer, will be performing the study.

The process of carrying out a scan usually takes around 20-30 minutes. Unless emergency patients delay you, your total time should be less than an hour.

No. You can drive afterwards and return to work as necessary.

Provided no other investigations are needed, you can eat and drink normally after your scan.

After the scan, we will examine the images further and prepare a report on our findings. This may take some time to reach your referring doctor but is normally less than 14 days. You could ask the radiologist/sonographer how long it might take to get the results. 

This leaflet is based on the NHS England website for Ultrasound scans. Ultrasound scan - NHS (accessed 05.05.2022)

NHS Constitution for England. Information on your rights and responsibilities. NHS Constitution for England - GOV.UK (accessed 05.05.2022)

Guidelines for Professional Ultrasound Practice (2021) Society of Radiographers and British Medical Ultrasound Society, (accessed 05.05.2022)

Sidhu PS, Cantisani V, Dietrich CF, et al (2018) The EFSUMB Guidelines and Recommendations for the Clinical Practice of Contrast-Enhanced Ultrasound (CEUS) in Non-Hepatic Applications: Update 2017 (Long Version). Ultraschall Med 39:e2-e44.

The EFSUMB Guidelines and Recommendations for the Clinical Practice of Contrast-Enhanced Ultrasound (CEUS) in Non-Hepatic Applications: Update 2017 (Long Version) (accessed 05.05.2022)

S.Weinstein et al.; How to set up a contrast enhanced ultrasound service. Abdom Radiol NY (2018) 43:808-818