Image Guided Liver Biopsy

Authors: Dr Ramon Pathi*
                            Dr James Burnes *

What are the prerequisites for having an image guided liver biopsy done?

Image guided liver biopsy can be targeted to a specific lesion (such as a suspected tumour) or be non-targeted in patients with suspected parenchymal liver disease, such as chronic hepatitis or cirrhosis. Non-targeted biopsies are carried out to make the diagnosis, assess the severity of disease and monitor treatment.

Almost all referrals for image guided liver biopsy come from specialists, usually from gastroenterologists, surgeons and oncologists. As a biopsy is an invasive procedure with some inherent risk, the decision to refer for biopsy should only be made after considering patient factors and diagnostic yield against risks.

Important investigations are required before an image guided liver biopsy.

• If a specific lesion is to be the subject of biopsy, recent cross-sectional imaging of the liver must be carried out and available to the radiologist on the day of the procedure (preferably in advance, so the best modality for imaging can be booked).
• Recent complete blood picture and INR. Any anticoagulant or antiplatelet therapy must be stopped for the appropriate period of time (usually 7-10 days for aspirin and clopidogrel) before INR. An INR of less than 1.3 is desirable.
• The timing of testing will be dictated by the patient’s clinical situation, but should be carried out as close to the procedure as possible. Acutely ill hospital inpatients should ideally have coagulation screening on the day of, or night before, the procedure.

The radiologists will weigh the risk of the procedure versus benefit of the biopsy if the patient has an elevated INR, and this risk should be discussed with the patient if possible.

Thrombocytopenia can also increase the risk of post-procedural haemorrhage. If the patient is thrombocytopenic (i.e. platelets less than approximately 140 x 10⁹/L), the radiologist should be made aware of this and steps will be taken to correct this as much as possible around the time of the procedure.

What are the absolute contraindications for an image guided liver biopsy?

There are no absolute contraindications (a diagnosis may be imperative). An uncontrolled bleeding tendency (i.e., uncorrectable INR, inability to cease clopidogrel due to drug-eluting coronary stents etc.) may warrant alteration or delay of the procedure. Alteration of the procedure may involve biopsy with gelfoam embolisation of the track, transjugular liver biopsy or open surgical biopsy.

What are the relative contraindications for an image guided liver biopsy?

Various bleeding tendencies are relative contraindications. Medication related bleeding tendency should warrant cessation of the particular drug, with sufficient time allowed for the effect of the drug to cease. For most antiplatelet and anticoagulant medication, 7–10 days is sufficient. However, in some patients, warfarin will need to be replaced by heparin, which is then ceased for a short time periprocedurally. This will require coordination between the referrer and radiology practice.

This will vary with the drug, and advice from the radiology practice undertaking the procedure is advised. Ascites increases the chance of bleeding, and consideration of draining the ascites a few days before liver biopsy is prudent. Patient obesity makes the biopsy more technically difficult, with increased risk profile. Ultrasound guidance is also impaired by obesity. The location of deep lesions, especially in segments 7 and 8, and those closer to the diaphragm are more difficult to biopsy, occasionally the increased difficulty and risk makes biopsy untenable.

What are the adverse effects of an image guided liver biopsy?

Bleeding is the main risk, usually manifesting only as increased discomfort and local pain (5% of biopsies). If the patient is haemodynamically stable, this can be treated with simple analgesia and the patient discharged after several hours of observation.

Any evidence of haemodynamic change may warrant intravenous fluids and haemoglobin check (1% of biopsies). Haemodynamic instability is very rare (0.1% of biopsies), and would require blood and fluid resuscitation, and may need US, CT or angiographic imaging in the event that embolisation or surgery are required. Tertiary institution management or transfer may be required. An absolute definition of clinically important ‘haemodynamic instability’ in this context is difficult and involves alteration from the patient’s previous measurements of heart rate and blood pressure that are unlikely to be accounted for by other drugs that may have been administered; for example, opiate analgesia, sedation, antihypertensive medication or comorbidities, such as the development of cardiac failure from other causes.

Inadvertent organ damage is rare, much less than 1%. This may include pneumothorax, bowel or gall bladder injury. These are most often self-limiting. It would be extremely rare for chest drain or abdominal surgery to be required for these respective complications.

Are there alternative imaging tests, interventions or surgical procedures to an image guided liver biopsy?

Some hepatic lesions have characteristic imaging appearances. Serial imaging (using ultrasound, multiphase CT, MRI +/- gadolinium or nuclear medicine red cell/sulphur colloid scans), rather than biopsy, can confirm the stability of probably benign lesions in individuals at low risk of primary or secondary malignancy or other serious pathology, such as an abscess. Taking this approach, which avoids the risks of biopsy, needs to be balanced against the possibility of delaying diagnosis of a malignancy.

A transjugular liver biopsy is an option for patients with a high risk of bleeding, such as those with liver failure and large amounts of ascites. In theory, any bleeding occurs back into the hepatic venous system and is therefore contained. It can only be used for parenchymal sampling (a specific lesion cannot be targeted). Any patient considered for transjugular biopsy should be discussed beforehand directly between the referrer and the interventional radiologist. In very rare circumstances, a lesion considered to be inaccessible might be amenable to transpleural or open surgical (+/- imaging) access, but this should be a multidisciplinary approach in a tertiary hospital setting.

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

Page last modified on 26/7/2017.