Contrast-enhanced ultrasound uses an intravenous agent that contains microbubbles. The contrast helps providers see the flow of blood through your organs and blood vessels. It can help detect a variety of diseases and conditions.
Ultrasound is a medical imaging test that healthcare providers use to see inside your body. Contrast is a substance that helps providers see the details of your internal structures more clearly during an ultrasound. Contrast is injected into one of your veins through an intravenous (IV) tube.
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Providers use CEUS most often to diagnose conditions of the liver and kidneys, such as:
CEUS can also help providers evaluate the functioning of certain organs and structures, including:
Providers may use CEUS along with or in place of other medical imaging tests, such as CT scans and MRI. The contrast agent in CEUS isn’t harmful to your kidneys unlike the contrast used CT scans. For people with kidney conditions or allergies to CT or MR contrast, CEUS may be a safer option.
For children, CEUS may also be safer than CT scans since it does not involve the use of X-rays.
A licensed provider such as a doctor, nurse practitioner or physician assistant and an ultrasound technician performs the test. A radiologist reviews the images and interprets the results.
An ultrasound uses a hand-held instrument called a transducer to send out high-frequency sound waves into your body’s tissue. You can’t hear the sound waves. Sound waves bounce off structures inside your body and back to the probe, which converts the waves into electrical signals. A computer then converts the pattern of electrical signals into real-time images or videos, which are displayed on a computer screen nearby.
The contrast agent in CEUS contains tiny, gas-filled microbubbles. The bubbles are smaller than the size of your blood cells. When sound waves from the ultrasound meet the contrast bubbles the bubbles vibrate and strongly reflect the sound waves. This creates a very light area in the image.
Because the contrast enters your body through your vein, CEUS shows how blood is flowing in your organs and blood vessels. Cancerous or diseased tissues usually have higher blood flow and look lighter on the ultrasound image.
The technician will perform a routine ultrasound first to locate the area of concern and gather baseline images. Afterward, you’ll receive the contrast agent and the technician will perform a second ultrasound.
The ultrasound technician will apply a small amount of clear gel onto your skin and place the transducer in the gel.
The technician will move the transducer around and angle it in different directions to capture the images. They may also ask you to roll onto your side, turn over or hold your breath for short periods of time. You will feel slight pressure from the transducer. This usually doesn’t cause pain unless you have some tenderness in that area.
A healthcare professional will insert a thin needle with a tube attached to it (IV) into a vein in your arm or hand to deliver the contrast solution. You may feel some slight discomfort from the needle and a cold feeling when the fluid enters your hand or arm. The technician will capture another set of images as the contrast moves through your organ or tissues. The process may be repeated if your provider determines it’s necessary or if there’s more than one area to evaluate.
The microbubbles in the contrast last only a short time. As the bubbles pop, the harmless gas dissolves in your blood and then exits your body when you breathe.
When the study is over, the technician will wipe off the gel and your IV will be removed. You will be able to go home immediately after the test is complete.
Usually, the only thing you need to do to prepare is to wear loose, comfortable clothing or change into a gown. Some tests for certain areas of the body may require additional preparation, such as:
Ultrasound technology is safe and has no harmful side effects. The contrast agent can cause side effects that range from mild to severe:
These are usually minor and get better on their own relatively quickly:
These may be similar to the mild side effects but require treatment, such as severe hives or vomiting. They may also include:
Anaphylaxis is an extremely rare and life-threatening side effect.
Mild physiologic side effects are uncommon, occurring in about 5% of people. Severe reactions are extremely uncommon, occurring in less than 0.01% of people.
The ultrasound images go to a radiologist for review and then to your healthcare provider. Your healthcare provider will let you know the test results.
A note from Cleveland Clinic
Healthcare providers use contrast-enhanced ultrasound most often to help diagnose conditions of the liver and kidneys. Aside from a slight needle prick of the IV, the procedure should not cause you any discomfort. Side effects from the contrast are rare. Make sure to follow any special instructions your provider gives you to prepare for the test. This will help the technician capture clear images and the radiologist make an accurate diagnosis.
Last reviewed by a Cleveland Clinic medical professional on 04/15/2022.
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Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy