Image Guided Liver Biopsy

Authors: Dr Ramon Pathi*
                            Dr James Burnes *

What is an image guided liver biopsy?

Image guided liver biopsy is a procedure where liver cells are obtained by a needle inserted directly into the liver through the abdominal wall, in the stomach area, and examined. The reason for requesting this test is that your referring doctor seeks an assessment of the liver tissue to look for any abnormality or disease that may be present. Imaging or pictures of the stomach area are used to guide accurate needle placement to make the procedure safer and avoid complications.

The two main imaging methods used for guiding the needle into the liver are ultrasound and computed tomography (CT).

There are two types of liver biopsy – core biopsy and fine needle aspiration (FNA). Either technique may need a ‘guide needle’, a slightly wider needle through which the sampling needle can be placed by the radiologist (specialist doctor) carrying out the biopsy. This is especially beneficial when multiple samples of liver tissue are needed. The radiologist carrying out the procedure will decide if a guide needle is necessary at the beginning of the procedure and will insert it before taking the samples with a smaller needle inserted through the guide needle.

Core biopsy

A core biopsy is used to assess the liver tissues when general liver disease, such as cirrhosis, is thought to exist. Core biopsies are now virtually never carried out in Australia without the use of imaging guidance, as it is recognised that it is safer for the doctor to be able to see the needle inside the patient throughout the procedure. This requires medical imaging. A core biopsy uses a large gauge needle (between 1–3 mm in diameter) and retrieves a thin cylinder of liver tissue.

Fine needle aspiration (FNA)

An image guided FNA is carried out with a much thinner needle and is used for taking a biopsy of a specific lesion (abnormality) or area within the liver. These too are nearly always carried out in Australia with image guidance.

How do I prepare for an image guided liver biopsy?

You will be required to fast (go without food and water) for 4–6 hours before a liver biopsy. This reduces the chance of stomach and bowel gas/contents interfering with the images of the liver during the procedure. Fasting also reduces any side-effects if you need to be given analgesics (pain killers) after the procedure.

Your referring doctor will have arranged for you to have any blood testing required as close as possible to when the liver biopsy is being carried out. Your doctor will also discuss with you the need to stop taking any anticoagulant or antiplatelet medication; that is, aspirin, clopidogrel and warfarin, usually 7–10 days before having the biopsy.

There is no other specific preparation.

What happens during an image guided liver biopsy?

You will be taken into the ultrasound or CT scanning room, and you will lie on the scanning bed. The radiologist will discuss the reasons for the biopsy, give a description of what will happen and discuss the risks. You will usually be asked to sign a consent form at this time.

A preliminary ultrasound or CT scan is carried out to plan the best way to perform the biopsy in your case. A nurse and radiographer will be present during the preliminary scanning, and the radiologist may also be present. Once the plan is decided, the nurse or radiologist will clean the surface of the skin where the needle will be inserted, and dress themselves in sterile gloves and possibly a gown.

The radiologist will first give a local anaesthetic into the abdominal wall, either below the right lower ribs or in between the lower ribs, to numb the area where the biopsy needle will be inserted.

This will sting sharply, but settles quickly.

The radiologist will make a small cut in the skin through which the biopsy needle is inserted and guided to the liver tissue or specific lesion or area. The needle causes a sharp sting when penetrating the outer surface of the liver (called the liver capsule), but pain is minimal after this. The biopsy is usually carried out with you holding your breath from time to time, under the radiologist’s instruction.

A core biopsy needle makes a ‘click’ noise when obtaining the sample; the FNA involves a ‘jiggling’ motion of the needle while you hold your breath.

After sufficient samples are obtained, firm pressure is applied with a gauze bandage to the entry site on the skin where the biopsy needle was inserted. You will then be taken to a recovery room, where you will be monitored for a number of hours. On rare occasions, you may be required to remain in hospital overnight.

Are there any after effects of an image guided liver biopsy?

The vast majority of patients find the procedure bearable, usually experiencing some discomfort, but not excessive pain. The most common side-effect is discomfort in the area of the biopsy. This may develop during or after the biopsy, or once the local anaesthetic has worn off. Any pain is normally controlled with analgesics (pain killers). Sometimes, this is given intravenously (directly into a vein in your arm).

Rarely, there are other more serious after effects associated with image guided liver biopsies. These are fully discussed in the question relating to the risks of image guided liver biopsies below.

How long does an image guided liver biopsy take?

It normally takes approximately 10 minutes for the preliminary ultrasound or CT scan, cleaning and dressing, and giving the local anaesthetic. The actual biopsy can take between a few seconds up to a minute. Depending on the reason for the biopsy and quality of the tissue sample obtained, it may be necessary to carry out several biopsies. The whole procedure is generally completed within 20–30 minutes.

Most patients are observed and have their blood pressure, pulse, comfort and so on checked over the next 4 hours. In some cases, patients may be required to remain in hospital longer and very rarely they may need to be kept in hospital overnight for observation.

What are the risks of an image guided liver biopsy?

Major effects are generally rare (less than 1% of cases). The potential risks of the biopsy include:

• Bleeding in the liver or abdominal wall and, on very rare occasions. Bleeding is usually mild and only results in pain/discomfort in less than 5% of cases. If bleeding is more severe, the patient may require having additional intravenous fluids or a blood transfusion, or in extreme cases, may require surgery or an interventional radiology embolisation procedure (where bleeding can be stopped using an angiogram procedure).
• Patient death as a result of bleeding after liver biopsy is an extremely rare event (perhaps 1/5000 chance).
• Damage of adjacent structures, such as the bowel, gallbladder or lung/pleura (the lining layer around the lung).
• A very small risk of spreading or ‘seeding’ of cancer cells along the needle track exists when a malignant lesion (cancerous tissue) is biopsied. Although this is recognised, the benefits of achieving a diagnosis are generally considered to outweigh this small risk.

What are the benefits of an image guided liver biopsy?

Image guided liver biopsy maximises the chances of obtaining a good sample of liver tissue in order to answer your doctor’s questions about potential liver abnormality or disease. Imaging also reduces (but does not entirely eliminate) the risks of complications. Image guided liver biopsy is normally required if a specific region or lesion in the liver is being investigated.

Who does the image guided liver biopsy?

A radiologist (specialist doctor) carries out the image guided liver biopsy. A radiology nurse may be involved in the set up of equipment and cleaning/preparation of the patient. If ultrasound is used for guidance, a sonographer may be involved in the preliminary scan or assist with imaging the biopsy. If CT is used, a radiographer will position the patient and assist with movement. If FNA is used, the radiologist will often have a pathologist in attendance to examine the tissue samples and ensure sampling is adequate. Pathologists are specialist doctors who examine tissue for the presence of abnormalities or disease.

Where is an image guided liver biopsy done?

Image guided liver biopsy can be carried out in any facility with the necessary imaging equipment and suitably trained health professionals, and facilities to monitor a patient afterwards. These would generally, but not always, be in larger radiology clinics or hospitals.

When can I expect the results of my image guided liver biopsy?

Your referring doctor will receive a report on the biopsy normally within a day or two. This is a notification and description of the results of the biopsy procedure.

In the event of any unexpected problem (such as bleeding during or shortly after the procedure), your doctor may be notified more promptly.

The time of availability of the liver biopsy result is determined by the pathology service, the type and number of tests that need to be carried out on the tissue samples, and the complexity of their interpretation. On average, this would be 2–3 days, but may be longer.

The time that it takes your doctor to receive a written report on the test or procedure you have had will vary, depending on:

• The urgency with which the result is needed;
• The complexity of the examination;
• Whether more information is needed from your doctor;
• Whether you have had previous X-rays or other medical imaging that needs to be compared with this new test or procedure (this is commonly the case if you have a disease or condition that is being followed to assess your progress);
• How the report is conveyed from the practice or hospital to your doctor (i.e. phone, email, fax or mail).

Please ask the radiology practice, clinic or hospital where you are having your test or procedure when your doctor is likely to have the written report.

It is important that you discuss the results with the doctor who referred you, either in person or on the telephone, so that they can explain what the results mean for you.

*The author has no conflict of interest with this topic.

Page last modified on 26/7/2017.