Diagnostic Ultrasound - Abdomen and Pelvis

Transjugular Intrahepatic Portosystemic Shunt (TIPS)
Diagnoses: Liver
TERMINOLOGY
• Shunt between main portal vein and hepatic vein created
with balloon-expandable covered metallic stent
IMAGING
• Goal of US: Detection of stenosis before shunt occludes or
symptoms recur
• Best imaging tool
○ US as primary TIPS surveillance tool
○ CTA/MRA indicated if US technically compromised or
equivocal
• Doppler US findings of TIPS malfunction
○ PV
– Hepatofugal flow
– Peak velocity < 35 cm/sec
○ Within shunt
– Peak velocity < 90 cm/sec or > 200 cm/sec at any point
– Temporal change in peak velocity > 50 cm/sec
KEY FACTS
TOP DIFFERENTIAL DIAGNOSES
• Portal vein occlusion
• Hepatic vein occlusion
• Inferior vena cava occlusion
PATHOLOGY
• Stenosis usually secondary to intimal hyperplasia from
hepatic venous side
• Hepatic encephalopathy if portal flow bypasses liver
CLINICAL ISSUES
• Most common symptoms/signs of stent malfunction
○ Variceal hemorrhage
○ Signs of worsening portal hypertension with increasing
ascites
DIAGNOSTIC CHECKLIST
• Low flow may be difficult to detect with US
○ Confirm angiographically (CTA, MRA, shunt venography)
(Left) Graphic shows TIPS
shunt creation. The hepatic
vein is punctured within 2 cm
of the inferior vena cava (IVC).
A covered stent is placed
between the hepatic venous
end and the right portal vein,
adjacent to its junction with
the main portal vein. (Right)
Spectral Doppler ultrasound of
a TIPS with interrogation at
the proximal (portal venous)
portion of the shunt shows
appropriate flow direction and
velocity of 139 cm/sec.
(Left) Spectral Doppler
ultrasound (same patient) in
the mid TIPS shows slight
increase in velocity to 178
cm/sec, which is still within
normal limits. Angle correction
should always be used when
evaluating TIPS for accurate
velocity measurement. (Right)
Anteroposterior supine portal
angiogram in a 66-year-old
man with a suspected TIPS
stenosis based on Doppler
ultrasound reveals multiple
areas of intimal hyperplasia
within the parenchymal
portion of the shunt ,
consistent with stenosis.
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