Budd-Chiari syndrome: Hepatic venous outflow obstruction

Global or segmental obstruction of hepatic venous outflow or inferior vena cava (IVC)

Ultrasound acute phase

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  Absent or restricted flow, possible thrombosis in hepatic veins (HVs)/IVC

  
  
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  Intrahepatic collateralization, bicolored HVs: Flow in opposite direction in HV branches with common trunk

  
  
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  Reduced velocity, continuous flow in portal vein, possibly hepatofugal flow

Ultrasound chronic phase

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  Hypertrophy of caudate lobe and unaffected segments, atrophy of involved segments, large regenerative nodules

  
  
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  Stenotic or occluded HVs/IVC

  
  
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  Intrahepatic &/or extrahepatic collateralization

CECT: Flip-flop enhancement pattern

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  Early enhancement of caudate lobe and central portion around IVC, decreased peripheral liver enhancement

  
  
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  Later decreased enhancement centrally and increased enhancement peripherally

  
  
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  Large regenerated nodules, hypertrophic caudate lobe

Liver cirrhosis

Portal vein thrombosis

Acute, severe passive venous congestion

Acute hepatitis

Imaging interpretation pearls

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  Narrowed or obliterated HVs/IVC

  
  
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  Bicolored HVs due to intrahepatic collateralization on color Doppler ultrasound

Use slow flow settings or B-flow imaging to show lack of flow in thrombosed hepatic veins

May see bicolored HVs due to intrahepatic collateralization on color Doppler ultrasound

Cine hepatic vein with grayscale (without moving transducer) to demonstrate flow (or confirm lack of flow) that is not detectable with color Doppler

Thrombosed HVs may be barely discernible or cord-like, requiring extra attention to locate on grayscale