Presentation
Hepatitis B diagnosed 2000. No previous liver imaging. Family history HCC ?cirrhosis ?portal hypertension ?hepatoma.
Patient Data
No focal liver lesion. Liver echotexture is normal. Smooth liver surfaces. Main portal vein measures 9 mm and demonstrates antegrade flow. No flow within ligamentum teres. Spleen measures 5.5 centimeters.
ARFI results:
- operator 1: median 1.13 m/s
- operator 2: median 1.11 m/s
Conclusion:
No sonographic evidence of cirrhosis or portal hypertension. No focal liver lesion. The two ARFI measurement sets are concordant in the <F2 range.
ARFI reference values:
- 1.35 - absent or mild fibrosis (F0 or F1)
- 1.35-1.55 - significant fibrosis (F2)
- 1.55- 1.80 - severe fibrosis (F3)
- >1.80 - cirrhosis (F4)
Based on meta-analysis of pooled data which included a predominance of HCV patients - Friedrich-Rust et al J Viral hepatitis 2012, 19 e212-1219.
These threshold values are not absolute and results should be interpreted in clinical context. Such things as inflammatory activity and venous congestion can elevate the ARFI value.
Case Discussion
Acoustic radiation force impulse (ARFI) is a type of shear wave elastography. In many institutions it is replacing the need (and the risk) of liver biopsies for the diagnosis of cirrhosis.