From the Guidelines
The ideal liver biopsy material is a specimen obtained with a 16 G needle, measuring >20 mm in length, for percutaneous medical liver biopsy.
Key Considerations
- For percutaneous medical liver biopsy, a 16 G needle is recommended, with a specimen length of >20 mm to provide adequate tissue for examination 1.
- If a smaller specimen is obtained, a second pass should be considered, especially for investigation of fibrosis stage or possible biliary disease 1.
- For targeted biopsy from a focal lesion, an 18 G needle is recommended, with an additional biopsy obtained from non-lesional tissue to evaluate background liver disease 1.
- For transjugular biopsies, at least two biopsies are recommended to be taken 1.
Biopsy Techniques
- Percutaneous liver biopsy is the most common type of biopsy, involving insertion of a thin needle through the skin into the liver and removing a small piece of tissue 1.
- Transjugular liver biopsy is a transvenous approach, favored when percutaneous liver biopsy is contraindicated or when additional investigations are required 1.
- Plugged liver biopsy is a modification of the percutaneous approach, advocated for patients with impaired coagulation or ascites where transjugular liver biopsy is not feasible 1.
From the Research
Ideal Liver Biopsy Material
The ideal liver biopsy material is a topic of ongoing discussion in the medical field. Several studies have investigated the optimal methods for obtaining liver tissue, including the type of biopsy and the characteristics of the specimen.
- Specimen characteristics: According to 2, the diagnostic value of liver biopsy is influenced by technical factors such as specimen number and size, with preferably ≥3 nonfragmented specimens of >20 mm in length.
- Biopsy methods: Different biopsy methods have been compared in terms of their diagnostic yield and complications. For example, 3 suggests that endoscopic ultrasound guided liver biopsy (EUS-LB) may have a greater diagnostic yield of tissue and be superior for a targeted approach of focal lesions compared to percutaneous and transjugular routes.
- Needle diameter and number of passes: The study by 2 also found that the needle diameter (1.6 mm Menghini) and number of passes (mean 2.5) can influence the diagnostic value of liver biopsy.
- Imaging guidance and operator experience: Imaging guidance and operator experience are also important factors in obtaining high-quality liver biopsy specimens, as noted in 4 and 2.
- Comparison of biopsy techniques: The study by 5 discusses the advantages and disadvantages of fine-needle aspiration (FNA) and core needle biopsy (CNB) in obtaining liver biopsy specimens, highlighting the importance of considering the specific clinical context and the expertise of the cytopathologist or surgical pathologist.
Complications and Risks
The risks and complications associated with liver biopsy are also important considerations.
- Bleeding risk: The study by 6 reports that complications, including bleeding, are relatively rare (0.06-0.32% of patients) but can be minimized with good technique and proper patient selection.
- Pain and other complications: Pain appears to be more common with percutaneous liver biopsy (PLB) compared to transjugular liver biopsy, as noted in 2.