What is a liver biopsy?
A liver biopsy is a procedure performed to remove a portion of the liver, which will be examined under a microscope for signs of damage or disease. As such, there are three main types of biopsy: laparoscopic, percutaneous and transvenous.
- Percutaneous liver biopsy: this is the most common technique for obtaining a liver sample. In this method, an incision is made in the abdomen, and a needle is inserted through the incision and into the liver to take a sample. Ultrasound, CT scans and other imaging techniques are often used to locate the liver. Some specialists omit the use of imaging techniques and locate the liver by palming the abdomen. Once the biopsy is completed, the patient should lie on his or her left side for up to two hours to reduce the risk of bleeding.
- Transvenous liver biopsy: This technique is used when the patient’s blood clots slowly or when there is excess fluid in the abdomen, a condition known as ascites. In transvenous biopsy, the patient lies face up on an X-ray table, a small incision is made in the neck and a tube is inserted into the jugular vein, into which a contrast liquid is injected to observe the veins. This liquid will illuminate when X-rays are used. The needle is inserted through the tube and the liver tissue samples are extracted. The patient must remain under observation for at least four to five hours to avoid the risk of bleeding.
- Laparoscopic liver biopsy: This type of biopsy is used to obtain a tissue sample from one or more specific areas of the organ or when there is a risk of infection or cancer spreading. During the test, the patient lies on his or her back, after which a sedative is administered. During laparoscopy, an incision is made in the abdomen under the rib cage, a tube called a cannula is inserted which is inflated with a gas, allowing the physician room to work in the abdominal cavity. The biopsy needle is inserted through the cannula. Any bleeding is easily captured with the camera and closed with electrical probes. The patient will need to be observed for several hours.
The liver is a vital organ that has several basic functions, including the following:
- Removes harmful products from the blood
- Fights infections
- Involved in the process of food digestion
- Stores energy
- Stores nutrients
Why is a liver biopsy performed?
A liver biopsy is performed at a time when it is difficult to make a diagnosis of whether or not there is a problem in the liver through blood tests or the use of ultrasound or x-rays with radiographs.
It is common for the biopsy to be done to estimate the level of existing liver damage, a process known as staging. Staging helps guide treatment.
In turn, the biopsy helps diagnose or detect:
- Liver cancer
- Cause of abnormal levels of liver enzymes detected in the blood.
- Cause of unexplained thickening of the liver organ
Snapshot of a liver biopsy, in which a sample of liver tissue is obtained and analyzed in the laboratory for a possible liver disease or problem.
Preparation for liver biopsy
The specialist should be fully informed about all medications the patient is taking, and may even be asked to stop taking any medications that affect blood clotting or that may interact with sedatives.
Some medications that may be prohibited both before and after a liver biopsy are non-steroidal anti-inflammatory drugs, anticoagulants, high blood pressure medications, diabetes medications, antidepressants, antibiotics, dietary supplements or asthma medications.
The patient may not eat or drink for at least eight hours before the biopsy, and will need to make arrangements for how he or she will return home, as driving will be prohibited for at least twelve hours. Prior to the procedure the patient will also have a complete blood test, to check, among other things, the ability to clot blood.
What does a liver biopsy feel like?
At the moment the needle is inserted to sedate the patient, the patient will feel a stabbing pain. Sometimes the patient may feel the biopsy needle as a deep pain that sometimes manifests itself in the shoulder.
With sedation, patients are helped to remain calm for the duration of the process. It is important to differentiate the process of sedation from anesthesia, because while with anesthesia the patient is unconscious, with sedation the patient can communicate with the medical team while sedated, but usually has no memory of the process.
Significance of abnormal results
Once the liver biopsy has been performed, there are two options. On the one hand, that the results are completely normal, a fact that will mean that the liver tissue is in a normal state.
On the other hand, liver biopsy can reveal the presence of various liver diseases, such as hepatitis or cirrhosis, as well as the presence of cancer cells or infections such as tuberculosis.
Some of the problems that can be identified by a liver biopsy are:
- Hepatocellular carcinoma
- Hodkin’s lymphoma
- Primary biliary cirrhosis
- Fatty liver
- Liver cancer
Advances in liver biopsy
The use and advancement of technology have brought about a series of changes in general medicine and in the liver biopsy process in general. On the one hand, it is worth highlighting the important progress that has been made in imaging techniques, which are sometimes sufficient to determine the state of the organ.
On the other hand, advances in treatments such as FibroScan, which measures the speed at which elastic waves propagate through the liver, thus assessing the degree of health of the liver.