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Liver Biopsy
Anne Larson, MD
University of Washington
What is a liver biopsy?
Liver biopsy is a diagnostic procedure used to obtain a small
amount of liver tissue. This tissue can then be examined under a
microscope to help identify the cause or stage of liver disease.
What are the different ways liver biopsy can be performed?
Percutaneous Liver Biopsy. The most
common way this liver sample is obtained is by inserting
a needle into the liver for a fraction of a second.
This can be done in the hospital and the patient may be
set home within 6 hours if there are no complications.
The physician determines the best location, depth, and
angle of the needle puncture by physical examination or
ultrasound. The skin and the area under the skin
is anesthetized. A needle is then passed quickly
into and out of the liver. Approximately half of
individuals have no pain afterwards, while another half
will experience brief localized pain that may spread to
the right shoulder. This usually lasts no longer
than 24 hours and is easily controlled by mild pain
medications.
Guided Liver
Biopsy. Another technique used is to guide the needle to the liver through
the abdomen or chest using images. This approach is used when there are
localized tumors identified by images created by ultrasound or computed
tomography (CT or “CAT” scan). Either ultrasound or CT scanning is used to
pinpoint the site of the tumor and guide the needle to this specific area
through the abdomen or chest. After this procedure, the patient is usually
allowed to go home the same day.
Less commonly used are laparoscopy, transvenous or transjugular
liver biopsy, and surgical liver biopsy. With laparoscopy, a lighted,
narrow tubular instrument is inserted through a small incision in the abdominal
wall. The internal organs are moved away from abdominal wall by gas that
is introduced into the abdomen. Instruments may be passed through
this lighted instrument or through separate puncture sites to obtain tissue
samples from several different areas of the liver. Patients who undergo
this procedure may be discharged several hours later. Transvenous or
transjugular liver biopsy may be performed by a radiologist in special
circumstances, e.g., when the patient has a significant problem with blood
clotting (coagulopathy) or a large amount of fluid within the abdomen (ascites).
With this procedure, a small tube is inserted into the internal jugular vein in
the neck and radiologically guided into the hepatic vein (which drains the
liver). A small biopsy needle is then inserted through the tube and
directly into the liver to obtain a sample of tissue. Finally, surgical
liver biopsy may be done at the time a patient undergoes an open abdominal
operation, enabling the surgeon to inspect the liver and take one or more tissue
samples as needed.
When is a liver biopsy used?
Liver biopsy is often used to diagnose the cause of chronic liver
disease that results in elevated liver tests or an enlarged liver. It is
also used to diagnose liver tumors identified by imaging tests (such as
ultrasound or CT scan). In many cases, the specific cause of the chronic
liver disease is highly suspected on the basis of blood tests, but a liver
biopsy is used to both confirm the diagnosis as well as the amount of damage to
the liver. Liver biopsy is also used after liver transplantation to
determine the cause of elevated liver tests and to determine if rejection is
present.
What are the dangers of liver biopsy?
The primary risk of liver biopsy is bleeding from the site of
needle entry into the liver, although this occurs in less than 1% of patients.
As noted above, about a third to a half of patients will experience some pain
after the biopsy. Other possible complications include the puncture of
other organs, such as the kidney, lung, or colon. Puncture of the
gallbladder may be associated with leakage of bile into the abdominal cavity,
causing peritonitis. Fortunately, the risk of death from liver biopsy is
extremely low, ranging from 0.1% to 0.01%.
Are there alternatives to liver biopsy? The primary alternative to a liver biopsy is to make the
diagnosis of a liver disease based on the physical examination of the patient,
medical history, and blood testing. In some cases, blood testing is quite
accurate in giving the doctor the information to diagnose chronic liver disease,
while in other circumstances a liver biopsy is needed to assure an accurate
diagnosis. Biopsy may also be needed to determine the severity of the
disease.
Do liver biopsies ever need to be repeated?
In most circumstances, a liver biopsy is performed only once to
confirm a suspected diagnosis of chronic liver disease. Occasionally,
liver biopsy is repeated if the clinical condition changes, or to assess the
results of medical therapy, such as interferon treatment of chronic viral
hepatitis, or the use of the drug prednisone to treat autoimmune hepatitis.
Patients who have undergone liver transplantation often require numerous liver
biopsies in the early weeks to months following the surgery to allow accurate
diagnoses of whether the new liver is being rejected or whether other problems
have developed.
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