Liver Imaging Findings in HHT
In a 53-year-old female with HHT, liver elastography would likely show normal or near-normal stiffness (since these patients do not have cirrhosis), while Doppler ultrasound would demonstrate characteristic findings of hepatic vascular malformations including an enlarged hepatic artery (>6 mm diameter), intrahepatic hypervascularization, elevated peak flow velocity (>80 cm/sec), and reduced resistivity index (<0.55). 1
Key Ultrasound Findings
The most critical and easily identifiable finding is hepatic artery enlargement, which serves as the simplest way to detect HHT-related hepatic abnormalities during routine ultrasound examination. 2
Doppler Ultrasound Characteristics
- Enlarged common hepatic artery is the hallmark finding, with diameter typically >6 mm (compared to normal <6 mm). 1, 3
- Intrahepatic hypervascularization appears as diffuse increased vascularity throughout the liver parenchyma. 1
- Elevated peak flow velocity >80 cm/sec in hepatic vessels (normal is lower). 4
- Reduced resistivity index <0.55, reflecting the low-resistance shunting through arteriovenous malformations. 4
- Heterogeneous hepatic enhancement pattern due to diffuse liver telangiectases and irregular blood flow. 1
Structural Liver Findings
- Nodular liver appearance is common, primarily due to nodular regenerative hyperplasia (NRH) from irregular hepatic blood flow—this is frequently misinterpreted as cirrhosis but is NOT cirrhosis. 1
- Focal nodular hyperplasia (FNH) occurs in 2.9% of HHT patients (100-fold higher than general population), which can be confused with hepatocellular carcinoma but is benign. 1
Elastography Interpretation
Liver stiffness measurements would be normal or only mildly elevated because HHT patients do not develop cirrhosis, and liver synthetic function remains preserved even when portal hypertension is present. 1 This is a critical distinguishing feature—the nodular appearance on imaging does NOT represent cirrhotic transformation.
Clinical Context at Age 53
At 53 years old, this patient falls within the typical age range for hepatic involvement in HHT (mean age 52 years). 5 However, only 8% of patients with hepatic vascular malformations are symptomatic, though longitudinal follow-up shows 25% will eventually develop morbidity. 6
Gender-Specific Considerations
Female patients with HHT have substantially higher prevalence and more symptomatic hepatic vascular malformations, particularly in HHT type 2 (ACVRL1 mutations). 5 Symptoms typically appear around age 30 years in females. 6
Critical Diagnostic Pitfalls to Avoid
- Never perform liver biopsy in any patient with proven or suspected HHT due to catastrophic hemorrhage risk from vascular malformations—biopsy is unnecessary, often misinterpreted, and dangerous. 1, 4
- Do not misinterpret nodular liver appearance as cirrhosis—the nodularity reflects NRH, not fibrotic transformation, and liver synthetic function remains normal. 1
- Do not mistake FNH for hepatocellular carcinoma—HCC has not been described in HHT, and any focal lesion should be characterized non-invasively using multiple imaging modalities. 1
When Hepatic Imaging Is Indicated
Routine screening for liver involvement in asymptomatic HHT patients is NOT recommended because prevalence is high (44-74%), most patients remain asymptomatic, and there is no effective treatment for asymptomatic vascular malformations. 1, 5
Screening should only be performed when:
- Establishing a definite HHT diagnosis in patients meeting only 1-2 Curaçao criteria. 1
- Evaluating symptomatic patients with suspected hepatic complications (high-output heart failure, portal hypertension, or biliary ischemia). 6, 3
Biochemical Correlation
If liver tests were obtained, the most common abnormalities would be elevated alkaline phosphatase and gamma-glutamyl-transpeptidase, though these are of little clinical significance when asymptomatic. 1 Notably, liver synthetic function and platelet count remain normal even in patients with portal hypertension, because there is no underlying cirrhosis. 1