Elastography for Liver Lesion Characterization

Guideline-Based Limitations

The American Gastroenterological Association (AGA) recommends elastography for assessing diffuse liver fibrosis and cirrhosis, but not for focal lesion characterization, with specific guidelines for diagnosing cirrhosis in chronic hepatitis C, hepatitis B, and nonalcoholic fatty liver disease 1, 2, 3, 4
The AGA guidelines provide recommendations for ruling out high-risk esophageal varices and assessing liver stiffness thresholds for portal hypertension 1, 5, 6

The American College of Radiology (ACR) recommends dynamic contrast-enhanced MRI as the most accurate modality for detecting and characterizing hepatocellular carcinoma (HCC), with sensitivity of 47-95% even for lesions <2 cm 7
The ACR also recommends multiphase contrast-enhanced CT, which shows sensitivity up to 98% for lesions >2 cm, though lower (40-68%) for smaller lesions 7
Contrast-enhanced ultrasound (CEUS) is an established characterization tool, while MR elastography has limited utility for screening and surveillance due to modest success and limited spatial resolution and coverage 7

Elastography should be used to assess the background liver parenchyma for fibrosis/cirrhosis staging, which informs the clinical context for interpreting detected focal lesions, with vibration-controlled transient elastography (VCTE) >11.0 kPa in hepatitis B suggesting cirrhosis and raising suspicion that a detected lesion could be HCC requiring 6-month surveillance 1, 2, 6, 10
Magnetic resonance elastography (MRE) can evaluate nearly the entire liver volume and maintains excellent applicability in obese patients where ultrasound-based methods fail 9
Normal elastography values (<6.8 kPa) indicate low risk for cirrhosis-related complications, making HCC less likely in detected lesions 8, 11