Worldwide, it is estimated that 360 million are infected with viral hepatitis B and 180 million with viral hepatitis C. Between 500,000 and 700,000 people die annually as a result of Hepatitis B virus infection. More than 350,000 people are estimated to die each year from Hepatitis C-related liver disease.
Chronic liver damage results in hepatic fibrosis, characterized by an increase in extracellular matrix material produced by fibroblast-like cells. This process results in liver fibrosis that can progress to cirrhosis with distortion of normal liver architecture and portal hypertension.
The gold standard for diagnosis and staging of liver fibrosis has been liver biopsy. However, in addition to being an invasive procedure with potential complications such as bleeding and severe pain, biopsy sampling error is a problem due to the small sample size in a diverse process.
In select patients, ultrasound elastography may eliminate the need for liver biopsy for staging fibrosis. Ultrasound imaging uses a small probe, called a transducer, and gel placed directly on the skin. High-frequency sound waves travel from the probe, through the gel, into the body. The probe collects the sounds that bounce back. A computer uses those sound waves to create the images for the exam.
Ultrasound elastography of the liver is painless and non-invasive.
When would I get an Ultrasound of the Liver?
Diffuse liver disease can result from many causes, including viral hepatitis (Hepatitis B or Hepatitis C), non-alcoholic or alcoholic fatty liver disease, autoimmune hepatitis, drug-induced liver injury, primary biliary cirrhosis and several other less frequent causes.
Your medical provider may recommend ultrasound elastography of the liver to stage the fibrosis of chronic liver disease such as:
- chronic viral hepatitis
- screening patients with Non-Alcoholic Fatty Liver Disease (NAFLD) to rule out nonalcoholic steatohepatitis, which is liver inflammation and damage caused by a buildup of fat in the liver
- determining the presence or absence of advanced fibrosis.
Accurately staging the degree of liver fibrosis is extremely important to determine if antiviral therapy is appropriate, and to predict treatment outcome and malignant potential. With current drug therapy, early stage fibrosis may be reversible.
What Will I Experience?
For most ultrasound exams, you will lie on your back on an exam table. You may have your position adjusted to either side in order to improve the quality of the images captured during the exam.
An ultrasound technologist will apply a warm water-based gel to the area of the body being studied. The gel will help the transducer make secure contact with the body and eliminate air pockets between the transducer and the skin that can block the sound waves from passing into your body. The transducer is placed on the body and moved back and forth over the area of interest until the desired images are captured.
There is usually no discomfort from pressure as the transducer is pressed against the area being examined. However, if scanning is performed over an area that is tender or sensitive, you may feel some pressure or minor discomfort from the transducer.
Once the exam is complete, the clear ultrasound gel will be wiped off your skin. Any portions that are not wiped off will dry quickly. The ultrasound gel does not usually stain or discolor clothing.
Typically, ultrasound elastography of the liver takes approximately 45 to 60 minutes to complete.