PERCUTANEOUS LIVER BIOPSY PROCEDURE

percutaneous liver biopsy procedure :
The most common reason for ultrasound-guided biopsy is for suspected metastatic disease. The liver is one of the most common sites for metastases and histology is often required to confirm the diagnosis, or to identify the origin of an unknown primary lesion. Biopsy of other focal lesions in patients with chronic liver disease (for example, cirrhosis, hepatitis B or C) in whom there may be suspected hepatocellular carcinoma and occasionally in patients with benign disease (for example, capillary haemangiomas or focal nodular hyperplasia) can also be performed, although MRI and contrast ultrasound are increasingly used to characterize lesions, without recourse to biopsy.

Focal lesion biopsy is generally safely and accurately performed with an 18G Tru-Cut needle which yields reliable tissue for histological analysis. In general an accuracy of 96% should be achievable. In addition to focal lesion biopsy another common reason for liver biopsy is to assess the presence/absence of parenchymal liver disease, severity of disease and, where appropriate, the aetiology of the disease process. This is often performed in patients with abnormal liver function tests with no evidence of biliary obstruction.

The clinical history and serological analysis can be helpful in determining aetiology; however biopsy is often required. This is normally performed with a 14G or 16G Tru-Cut needle. Very often the liver is simply identified with ultrasound and a suitable mark made on the skin, often in the mid-axillary line, and the biopsy performed through the right lobe.

Although this is acceptable for this type of biopsy, as no guidance is required towards a specific focal lesion, ultrasound guidance during the procedure is still preferable to the ‘blind’ technique in order to avoid large vessels and reduce the subsequent risk of haematoma. Biopsy may also be performed for patients with suspected rejection following hepatic transplantation. Where coagulation profiles are not correctable (and most generally are), liver biopsy can be performed using a ‘plugged’ technique or, more commonly, by the transjugular route.