Elastography

What is elastography?

Elastography is a test that uses painless, low-frequency vibrations to check the elasticity of your body’s organs. When tissues lack elasticity and are stiff, it may signal disease, especially in the liver.

What are the types of elastography?

There are two main types of elastography:

• Elastography ultrasound: Also called transient elastography (FibroScan®), this noninvasive test uses a handheld wand (transducer) and sound waves to produce an image of your organs. The ultrasound is painless and fast.
• MRE (magnetic resonance elastography): This test combines sound waves from an ultrasound with magnet and radio waves from an MRI to produce images of your organs. It doesn’t use any radiation. While an MRE is its own test, your provider may choose to combine the MRE with a full MRI.

What is shear wave elastography?

Shear wave elastography is a newer ultrasound technology used to check tissue stiffness. A transducer delivers high-intensity pulses that produce shear waves, which create a higher-quality image. While still in development, shear wave elastography is used in ultrasounds of the:

• Breast.
• Liver.
• Musculoskeletal system.
• Prostate.
• Thyroid nodule.

What is the purpose of elastography?

The most common reason for elastography is to check your liver for fibrosis, which happens in the early stages and may advance to late stage or cirrhosis of your liver. Your provider may order elastography if you have risk factors, signs or symptoms of cirrhosis.

Fibrosis can lower the amount of blood flow that goes through your liver, causing the blood to back up behind your liver over time. If left untreated, liver fibrosis can result in serious health problems like:

• Cirrhosis.
• Liver cancer.
• Liver failure.
• Gastrointestinal bleeding.

Liver elastography can help healthcare providers make treatment recommendations for liver fibrosis. They can also use this test to monitor your liver’s response to treatment and predict liver disease complications like fatty buildup.

Who performs elastography?

A radiologist performs elastography ultrasounds and MREs. These physicians are experts in using medical imaging technology. They often work closely with other healthcare professionals such as primary care providers, oncologists and hepatologists (liver specialists).

How accurate is liver elastography?

While research varies, most healthcare providers agree that elastography can accurately diagnose liver fibrosis. Many providers use elastography to diagnose this condition. More importantly, it’s used to monitor the disease progression over time.

How is elastography performed?

The way elastography is performed depends on the type:

Steps for transient elastography, which takes only a few minutes, include:

1. The radiologist applies clear, water-based gel to your skin to help reduce friction.
2. The radiologist moves the handheld wand (transducer) around your skin to find the proper organ.
3. The wand sends painless, low-frequency vibrations into the body.
4. The vibrations strike the organ and bounce back, sending information to a computer.
5. The computer turns the information into an image of the organ.
6. The radiologist can see the organ’s size, shape and consistency — including stiffness or whether it’s filled with fluid.

An MRE usually takes five minutes, but if you’re having a full MRI, it will take longer — about 45 minutes. During an MRE, your provider:

1. Helps you lay on a table, which might have straps to help you keep still.
2. Places a small device (driver) on the right side of your lower chest (for a liver MRE).
3. Places devices that send and receive radio waves near the driver on the skin.
4. Injects the contrast (gadolinium) into an IV line that’s inserted in your hand (if you are having an MRI with contrast).
5. Helps you enter the MRI unit, a tube-like machine.
6. Stays near a computer outside of the MRI unit.
7. Asks you to hold your breath for a few moments as the driver directs small vibrations toward your liver to capture images of it.

How do I prepare for the elastography?

Preparations for elastography may include:

• Food: Don’t eat or drink anything high in sugar before the test. Sugary products can affect liver stiffness. Fasting instructions may vary, so ask your provider if you should stop eating and drinking before the test (and for how long).
• Clothing: On the day of the exam, leave your jewelry and accessories at home. This includes wedding rings, watches, hairpins, hearing aids and removable dental work. Wear loose-fitting clothes. You may have to change into a medical gown for the procedure.
• Metal: Tell the radiologist if you have any metal in your body, including shrapnel, bullets, older cardiac defibrillators or pacemakers. Metal can interfere with the magnetic field from the MRI unit.
• Pregnancy: Make sure to tell your provider and the radiologist if you’re pregnant. Elastography is generally safe during pregnancy, but pregnant women should avoid MRI in the first trimester unless the benefits outweigh the risks.

What should I expect during the elastography?

During the procedure, your radiologist will walk you through everything that will happen. Both ultrasound elastography and MRE are painless, noninvasive procedures, so you won’t feel any pain or discomfort.

If you’re having an MRE, you will spend a few minutes in a tube-like space. If you’re having a full MRI, it will take longer — about 45 minutes. Talk to your provider and the radiologist beforehand if you have claustrophobia. Also, be prepared to hold your breath for 10 to 15 seconds at a time during the MRE.

What are the risks of elastography?

There are no known risks associated with an elastography ultrasound.

When proper safety guidelines are followed, an MRE has no risks for the average patient. The magnetic field is not harmful. If you receive sedation, there are risks associated with too much sedative. There’s also a small risk of allergic reaction to the gadolinium contrast solution, which is only used for some MRI procedures.

What type of results will I get from elastography, and what do the results mean?

Your elastography produces an image of your liver. The image shows the radiologist the level of stiffness, which indicates scarring. The level of scarring ranges from mild to advanced:

• F0 to F1: None or mild scarring.
• F2: Moderate scarring.
• F3: Severe scarring.
• F4: Advanced scarring (cirrhosis).

When will I know the results of the elastography?

The radiologist determines your elastography results within a few days of the scan. They’ll share the results with other referring providers as needed. One of the providers notifies you to review the results and answer your questions.

A note from Cleveland Clinic

Elastography is a noninvasive test used to check the stiffness of the organs. It’s mostly used to look at the liver for signs of fibrosis. Your provider may order elastography if you’ve had inflammation or damage to the liver or have symptoms of cirrhosis. The test is usually quick and painless. Talk to your provider if you have any questions or concerns.