Technique using short-duration acoustic pulses to assess tissue stiffness
Expansion
Acoustic Radiation Force Impulse
Purpose
Quantifies liver fibrosis non-invasively; less operator-dependent than standard elastography
Clinical Context
ARFI generates localised shear waves; velocity correlates with elasticity. Units metres per second. Normal liver less than 1.3 metres per second; cirrhosis greater than 1.8 metres per second.
Related Terms
- SWE
- Elastography
- Fibroscan
Key Points
- ARFI measures shear wave velocity reflecting tissue stiffness; high velocity equals fibrosis or cirrhosis