Diagnostic Ultrasound - Abdomen and Pelvis

Portal Vein Abnormality
Differential Diagnoses: Liver
DIFFERENTIAL DIAGNOSIS
Common
• Portal Hypertension
• Portosystemic Collaterals
• Bland Portal Vein Thrombosis
• Portal Vein Tumor Thrombus
• Pulsatile Portal Vein
Less Common
• Portal Vein Gas
ESSENTIAL INFORMATION
Helpful Clues for Common Diagnoses
• Portal Hypertension
○ Decreased portal vein mean velocity (< 16 cm/s)
○ Portal venous pressure ≥ 10 mm Hg more than inferior
vena cava pressure
○ Hepatofugal portal vein flow in severe portal
hypertension
○ Absent (aphasic) portal venous flow due to stagnation
– Lack of respiratory phasicity
– Severe portal hypertension
○ Development of portosystemic shunts
○ Background cirrhosis, splenomegaly, ascites, thickened
bowel wall
• Portosystemic Collaterals
○ Common locations
– Inferior hepatic margin via gastroepiploic vein
– Gastroesophageal junction via left gastric vein
– Anterior abdominal wall via ligamentum teres
(recanalized paraumbilical vein)
– Lienorenal ligament via lienorenal collaterals
○ Color Doppler shows low velocity hepatofugal flow
• Bland Portal Vein Thrombosis
○ Echogenic material within portal vein (acute thrombosis)
○ Poor visualization of portal vein (chronic thrombosis)
○ Cavernous transformation of portal vein in chronic
thrombosis
○ Color Doppler: Interrupted/irregular flow in portal vein
○ Signs of liver dysfunction or portal hypertension
– Cirrhosis, ascites, splenomegaly, portosystemic
collaterals
• Portal Vein Tumor Thrombus
○ Majority arise from hepatocellular carcinoma
○ Echogenic material within portal vein
○ Suspect tumor thrombus in case of adjacent hepatic
malignancy
○ Color Doppler may show tumor neovascularity within
thrombus
• Pulsatile Portal Vein
○ Normal portal vein waveform
– Hepatopetal and mildly phasic (gentle undulation)
○ Increased pulsatility (pulsatile waveform)
– When there is large difference between peak systolic
velocity and end diastolic velocity
□ Tricuspid regurgitation
□ Right-sided congestive heart failure
□ Arterioportal shunting in cirrhosis
□ Arteriovenous fistula in hereditary hemorrhagic
telangiectasia
Helpful Clues for Less Common Diagnoses
• Portal Vein Gas
○ Highly reflective foci (gas) travels within portal vein
○ Poorly defined, highly reflective parenchymal foci
○ Gas moves to periphery of liver (as opposed to biliary
gas, which moves towards liver hilum)
○ High intensity transient signals (HITS) with spectral
Doppler
– Strong transient spikes superimposed on portal
venous flow pattern
SELECTED REFERENCES
1. Manzano-Robleda Mdel C et al: Portal vein thrombosis: What is new? Ann
Hepatol. 14(1):20-7, 2015
2. McNaughton DA et al: Doppler US of the liver made simple. Radiographics.
31(1):161-88, 2011
3. Abboud B et al: Hepatic portal venous gas: physiopathology, etiology,
prognosis and treatment. World J Gastroenterol. 15(29):3585-90, 2009
(Left) Spectral Doppler
ultrasound of the liver in a
patient with portal
hypertension shows
retrograde (hepatofugal) flow
in the portal vein ſt, a finding
that appears blue on the color
Doppler US and is displayed
below the baseline on the
spectral waveform . (Right)
Transverse abdominal color
Doppler US in a patient with
hepatic cirrhosis shows a
recanalized paraumbilical vein
ſt arising from the left portal
vein and traveling
anteriorly along the falciform
ligament towards the inferior
epigastric vein.
Portal Hypertension
Portosystemic Collaterals
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