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What Is A Liver Biopsy?
Liver biopsy is a diagnostic procedure used to obtain a small amount of liver
tissue, which can 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?
The most common way a 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 sent home within 3-6 hours if there are no complications.
The physician determines the best site, depth, and angle of the needle puncture
by physical examination or ultrasound. The skin and area under the skin is anesthetized,
and a needle is 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.
Another technique used for liver biopsy is guiding the needle into the liver
through the abdomen or chest using various imaging techniques. This approach
is used when there are localized tumors identified by ultrasound or computed
tomography (CT). 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 biopsy techniques 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 the 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, 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 biopsy
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. 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 confirm the diagnosis as well
as determine the amount of damage to the liver. Liver biopsy is also used after
liver transplantation to determine the cause of elevated liver tests and 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. Other possible
complications include the puncture of other organs, such as the kidney, lung
or colon. Biopsy, by mistake, of the gallbladder rather than the liver 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.
Do Liver Biopsies Ever Need To Be Repeated?
In most circumstances, a liver biopsy is only performed 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 drug treatment of chronic viral hepatitis with interferon or prednisone
therapy of 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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