New imaging assisted methods for liver fibrosis quantification: Is it really favorable to classical transient elastography?
Non-invasive evaluation of liver fibrosis is now an inescapable tool for patient assessment and follow-up in fibrotic diseases such as hepatitis B or C, but also in alcoholic liver disease (ALD) or non-alcoholic fatty liver disease (NAFLD). The gold standard liver biopsy carries risks and could be considered as an aggressive method compared to non-invasive investigations. Liver biopsy has been challenged by low reproducibility in blinded histological comparison studies and a larger liver parenchyma analysis compared to the limited microscopic analysis of a liver fragment is potentially attractive. Taken together, these data support the utilization and the development of non-invasive techniques for liver fibrosis quantification replacing or in addition to liver biopsy. Transient elastography (Fibroscan), one of the first in vivo methods directly evaluating liver stiffness, presents an acceptable profile with cut-offs being validated principally in the setting of liver fibrosis due to chronic hepatitis C but also for liver cirrhosis of other various etiologies. New imaging techniques were further developed, including acoustic radiation force impulse (ARFI) and more recently supersonic shear wave imaging (SSI). Both techniques allow the selection of the surface of interest (through a coupled standard 2D ultrasound image) to perform fibrosis quantification. In a recent paper published in the Journal of Hepatology, Cassinotto et al. compared SSI to histological fibrosis score, ARFI and FibroScan. In this letter, we comment on data interpretation and conclusions.