Liver Doppler, TIPS Evaluation, and Liver Transplant Assessment

normal flow within the portal veins should be

hepatopetal, continuous, monophasic, and have low velocity

velocity of the normal portal vein

between 20 and 40 cm per second

because of their close association with the left atrium, the hepatic veins typically demonstrate

a triphasic flow pattern

deep inspiration may result in — of hepatic vein pulsatility

blunting or complete loss

the hepatic artery should demonstrate

a continuous, low resistance wave form pattern, with a quick upstroke, and a gradual deceleration with diastole

the normal resistive index of the hepatic artery is

between 0.5 and 0.8

in patients with advanced cirrhosis and portal hypertension, a TIPS stent may be inserted via the

jugular vein

a TIPS stent is usually placed between

a hepatic vein and intrahepatic portion of the portal vein

most often, the shunt is created between the

right portal vein and the right hepatic vein, and a bridging stent is left in place

a stent reduces the amount of

blood flow to the liver by rerouting the blood coming from the portal vein to the hepatic vein, ultimately sending the blood back to the heart

the primary goal of TIPS

is to prevent the rupture and hemorrhage of gastroesophageal and other varices, an occurrence that is often fatal

on sonography, TIPS appears as a

highly echogenic tube within the liver

it may be noted that flow within the right and left portal veins typically

reversed after stent placement

the normal flow velocity within the shunt ranges between

90 and 190 cm per second

the signs of TIPS failure include

signs of clot within the shunt, stenosis of the shunt, stenosis of the hepatic vein, reversal of intrahepatic flow, flow void next to the stent, reversal of hepatic venous flow, drop in shunt velocity between examinations, and abnormally high or low shunt velocity

TIPS sonographic appearance. the wall of the TIPS appears highly echogenic. TIPS, transjugular intrahepatic portosystemic shunt

color image of a normal TIPS

— is the most common liver disease requiring a liver transplant, closely followed by alcoholic liver disease and cirrhosis

hepatitis C

the transplanted liver is attatched end to end to the native — & — termed — and a “—” attachment is made between the donor and recipient IVC

portal vein & hepatic vein; piggy back

a liver transplant should appear similar to

a normal native liver

although often with acute rejection the liver appears normal, suspicion should arise when the liver appears

diffusely heterogeneous

is the most common vascular complication of a liver transplant

hepatic artery thrombosis

when hepatic artery thrombosis is suspected, the sonographer should closely evaluate the liver for signs of

infarction

infarction appears as

hypoechoic wedge-shaped area scattered throughout the periphery of the liver

other complications of liver transplants include

biliary strictures, cholangitis, biliary sludge and stones, hepatic artery stenosis, hepatic artery pseudoaneurysms, celiac artery stenosis, portal vein stenosis and thrombosis, and fluid collections, including ascites, hematomas, bilomas, and abscesses

if present, stenoses, strictures, adn pseudoaneurysms are often discovered at

anastomotic site

TIPS failure. this occluded TIPS lacks color flow filling and echogenic material (clot) can be noted within the shunt

liver transplant. diagram demonstrating the most common surgical anatomy following liver transplantation with an interposition IVC graft. IVC, inferior vena cava