What role does ultrasound play in the diagnosis of liver fibrosis?
In the past, the diagnosis of liver fibrosis was dependent on liver biopsy. The patient’s resistance to liver biopsies has driven the ongoing development of various methods of detecting liver fibrosis, such as through the use of ultrasound.
In general, ultrasound examinations of the liver use B-mode real-time ultrasound (commonly known as “black-and-white ultrasound”), and this type of examination can aid in the understanding of morphological changes affecting the liver as a whole.
In addition, ultrasound evaluation of the liver can detect liver calculus, liver cirrhosis, hepatic cysts, liver abscess, and liver nodules or tumors.
Liver stiffness depends on numerous factors, and fibrosis is an important factor influencing liver stiffness.
However, additional factors that may affect liver stiffness include:
(1) acute or chronic hepatitis (inflammation),
(2) blood volume,
(3) liver perfusion,
(4) fatty infiltration,
(6) heart failure/central venous pressure, and
(7) whether the patient is fasting.
A meta-analysis of 1163 cases of chronic liver disease compared the accuracies of ARFI and TE. ARFI had a relatively low measurement failure rate compared with TE (2.1% vs. 6.6%) . ARFI and TE had similar sensitivities of 74% and 78%, respectively, when used to diagnose significant fibrosis, and 87% and 89%, respectively, when used to diagnose liver cirrhosis. Specificity was also similar, at 83% and 84%, respectively, in the case of significant fibrosis, and 87% and 87%, respectively, in the case of liver cirrhosis.
The limitations of ARFI are similar to those of conventional ultrasound and include high operator dependence. In addition, ARFI has a narrow range of values (0.5–4.4 m/s), which may restrict optimal cutoff values.
To overcome these problems, alternative methods of assessing liver fibrosis, such as those based on ultrasound, have been developed in recent years. Current clinical evidence indicates that TE and ARFI are able to not only assess liver fibrosis, but can also be used to predict prognosis.In practical, ULTRASOUND can also be used on a regular basis to evaluate the degree of liver fibrosis for chronic hepatitis B and C, nonalcoholic fatty liver disease, and alcoholic liver disease.
- Berzigotti, A., De Gottardi, A., Vukotic, R. et al.Effect of meal ingestion on liver stiffness in patients with cirrhosis and portal hypertension. PLoS One. 2013
- Talwalkar, J.A., Kurtz, D.M., Schoenleber, S.J. et al.Ultrasound-based transient elastography for the detection of hepatic fibrosis: systematic review and meta-analysis.
- Palmeri, M.L., Wang, M.H., Dahl, J.J. et al.Quantifying hepatic shear modulus in vivo using acoustic radiation force. Ultrasound Med Biol. 2008