Imaging Based Methods of Liver Fibrosis Assessment in Viral Hepatitis: A Practical Approach

Table 1

Salient features of technical aspects of liver elastography modalities.

Technique	TE	ARFI	SWE	RTE	MRE
Liver morphologic examination/image	Unable because of; lack of visualization	Available as; integrated with ultrasound	Available as; integrated with ultrasound	Available as; integrated with ultrasound	Best as; integrated with MRI
Type of force	Dynamic	Dynamic	Dynamic	Static	Dynamic
Applied Force	External mechanical impulse	Internal acoustic beam	Multiple internal acoustic beams	Heart beat	External driver device
Region of Interest (ROI)	Monodimensional ROI: 1 × 4 cm area	Monodimensional ROI: 1 × 0.5 cm	Multiple real-time color-coded elasticity imaging: 2D images; ROI: up to 5 cm × 5 cm	Not a quantitative approach: “Relative Elasticity”	Evaluates the entire liver with 2D-3D images
Measurement results (LSM)	Quantitative results displayed in kPa	Quantitative results displayed often in m/s	Quantitative results displayed in kPa or m/s at a wide range of values	Qualitative	Quantitative results displayed in kPa