Magnetic resonance imaging MRI uses a magnetic field and radio waves to produce detailed pictures of the liver. MRI is the most sensitive imaging test for steatosis, highly accurate even in mild steatosis. When a special technique is used, MRI can calculate the percentage of fat in the liver. Ultrasound elastography is a special ultrasound technique to test for liver fibrosis.
The movement of the liver caused by ultrasound wave is measured in the middle of the liver, and its stiffness or elasticity is calculated. Fibrotic livers are stiffer and moves to a greater degree compared to normal livers. The movement of fine vibration waves in the liver is imaged to create a visual map, or elastogram, that shows the stiffness or elasticity across the liver.
Both ultrasound and MR elastography can detect increased stiffness of the liver caused by liver fibrosis earlier than other imaging tests and may eliminate the need for an invasive liver biopsy. Liver biopsy is an image-guided procedure that removes a small sample of liver tissue using a needle. The sample is then examined under a microscope for signs of steatosis, inflammation and damage, and fibrosis.
For example, therapies for NAFLD may include: dietary changes anti-inflammatory medications and medications for insulin resistance cholesterol and diabetes management exercise and weight loss eliminating alcohol use. Send us your feedback Did you find the information you were looking for? Yes No. Area Code:. Phone no:. Radiologist prepping patient for abdominal ultrasound exam. View full size with caption. Sponsored By. Please note RadiologyInfo. Two terms used to describe this are fibrosis and cirrhosis.
Fibrosis means that healthy liver tissue is starting to be replaced by scar tissue, hardening the liver and interfering with its functions.
Fibrosis progresses over time in people with hepatitis B or hepatitis C, and this tends to happen faster in people who also have HIV. Fibrosis can be partially reversed if the cause is identified and dealt with early enough. Cirrhosis is severe scarring of the liver. Scar tissue replaces the cells that carry out the liver's normal functions and can block the flow of blood through the liver.
Unlike healthy liver cells, scar tissue cells cannot self-repair or otherwise function. Scar tissue from fibrosis can also block or limit the flow of blood within the liver. This can starve and eventually kill healthy liver cells, creating more scar tissue in the process. Treatment tends to involve clearing infections, making lifestyle changes, and taking certain medications.
This can often reverse the damage of mild to moderate liver fibrosis. If inflammation continues, possibly because a person has not received treatment, liver fibrosis can develop into more serious liver conditions. In this article, we will discuss the causes of liver fibrosis, how doctors measure the extent of damage, how symptoms change over time, and the treatments available.
If a doctor believes that someone has liver fibrosis, they will carefully collect a small tissue sample, or biopsy, from the liver using a large needle. A pathologist, which is a doctor who specializes in finding the root cause of disease, will then examine the sample under a microscope. They do this to assess the extent and type of damage.
Determining the degree of fibrosis is difficult because pathologists only have a small sample to work with. Other doctors can also assess the same sample in different ways. Healthcare providers can use several scales to define the stages of fibrosis. These include the Metavir, Ishak, and Batts—Ludwig scales. These and similar scoring systems take into account the effect that the fibrosis has had on the portal vein, which delivers blood from the intestines to the liver.
Many scales also measure the extent of fibrosis and the location or number of septa, which are fibrous bands of tissue in the biopsy sample.
The Metavir scoring system rates the progression of fibrosis on a scale from A0 to A The Metavir system also scores the level of fibrosis from F0 to F Cirrhosis is scar tissue building up in the liver.
This can occur due to unchecked fibrosis. Learn more about cirrhosis here. The most advanced type of fibrosis someone can have before developing cirrhosis, according to the Metavir system, is stage A3F3. Using the Ishak scale, the most advanced stage of fibrosis a person can have before developing cirrhosis is stage 5. The Batts—Ludwig scale , common in the United States, is slightly simpler.
This scale runs from 0 to Using the Batts—Ludwig scale, the most advanced stage of fibrosis a person can have before developing cirrhosis is stage 3.
People with fibrosis are usually unaware that they have it. This is because it rarely causes any obvious symptoms.
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