How is a Fibroscan (Fibrosis Scan) result interpreted in patients with suspected liver disease?

Interpreting FibroScan Results in Suspected Liver Disease

FibroScan results should be interpreted using disease-specific cutoff values, with values >7.0 kPa indicating significant fibrosis (≥F2) and values >12.5 kPa indicating cirrhosis (F4) in chronic hepatitis B patients, while in NAFLD/MASH patients, values <8.0 kPa rule out significant fibrosis and values >12.0 kPa suggest advanced fibrosis. 1, 2

Disease-Specific Interpretation Guidelines

Chronic Hepatitis B

• <7.0 kPa: Minimal to no significant fibrosis
• >7.0 kPa: Significant fibrosis (≥F2) - consider antiviral therapy regardless of viral load or ALT levels 1, 2
• >12.5 kPa: Cirrhosis (F4) - priority for antiviral treatment 1

NAFLD/MASH

• <8.0 kPa: Low risk for clinically significant fibrosis (F2-F4) - repeat surveillance in 2-3 years 1, 2
• 8.0-12.0 kPa: Indeterminate risk - consider additional testing or specialist referral
• >12.0 kPa: High risk for advanced fibrosis - refer to hepatologist 1

Alcoholic Liver Disease

• <11.0 kPa: Likely rules out significant fibrosis 3
• ≥11.7 kPa: Significant fibrosis (≥F2)
• ≥15.2 kPa: Severe fibrosis (≥F3)
• ≥21.2 kPa: Cirrhosis (F4)
• >30.6 kPa: Clinically significant portal hypertension (HVPG >10 mmHg) 3

Diagnostic Accuracy and Reliability

FibroScan demonstrates excellent diagnostic accuracy with:

• Area under ROC curve of 0.95 for significant fibrosis and 0.98 for cirrhosis in HBV patients 4
• High negative predictive values (>90%) for ruling out advanced fibrosis 1, 3
• Superior performance compared to serum biomarkers like APRI and FIB-4 4

Factors Affecting Measurement Reliability

For valid liver stiffness evaluation (LSE), ensure:

1. ≥10 successful measurements
2. IQR/median ratio <0.30
3. ≥60% measurement success rate 5

Factors that can affect measurement accuracy:

• Operator experience: Validity rates improve significantly after the first 10 scans 5
• Acute inflammation: Avoid during acute hepatitis or flares
• Recent alcohol consumption: Ensure at least 1 week of abstinence before testing 2
• Elevated transaminases: Can falsely elevate readings 6
• Obesity: May limit technical success

Clinical Decision-Making Algorithm

1. Obtain FibroScan measurement ensuring validity criteria are met
2. Interpret based on underlying liver disease etiology using appropriate cutoffs
3. For low values: Schedule follow-up monitoring (every 2-3 years)
4. For indeterminate values: Consider additional testing (APRI, FIB-4, MR elastography)
5. For high values: Refer to hepatologist for consideration of:
   • Disease-specific treatment (antivirals for viral hepatitis)
   • Additional testing (liver biopsy if discordant results)
   • Screening for complications (varices, hepatocellular carcinoma)

Common Pitfalls to Avoid

• Don't rely solely on FibroScan: Integrate with clinical, laboratory, and other imaging findings
• Don't ignore technical validity criteria: Invalid measurements significantly reduce diagnostic accuracy 5
• Don't use generic cutoffs: Apply disease-specific thresholds for accurate interpretation 1, 2
• Don't scan during acute inflammation: Wait until resolution to avoid falsely elevated readings 2, 6
• Don't ignore significant variations: Short-term variations of >20% occur in nearly half of paired measurements 6

Sequential Testing Approach

For optimal accuracy, consider a two-tier approach:

1. First tier: Blood-based markers (FIB-4, APRI)
2. Second tier: FibroScan for patients with indeterminate or high scores on blood tests 1, 2

This sequential approach improves diagnostic accuracy compared to using individual tests alone, particularly in patients with metabolic risk factors or diabetes 1.