Diagnostic Tests

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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 a 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 to 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 are 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). For this reason, transjugular liver biopsy is recommended for

patients with advanced cirrhosis. 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%.

In order to reduce the risk of bleeding, the coagulation status is assessed

in all patients prior to a biopsy. If the prothrombin (coagulating) time is

too slow or the platelet count is low, a standard biopsy is not recommended.

Vitamin K or fresh frozen plasma may be used to correct clotting

abnormalities in such instances. Another alternative in this situation would

be a transjugular biopsy.

Are There Alternatives to Liver Biopsy?

The primary alternative to 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.