Articles
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73 results found
Article
Triangular cord sign (biliary atresia)
The triangular cord sign is a triangular or tubular echogenic cord of fibrous tissue, representing the ductal remnant of the extrahepatic bile duct, seen in the porta hepatis at ultrasonography, and is relatively specific for the diagnosis of biliary atresia 1,2.
This sign is useful in the eval...
Article
Atoll sign (liver MRI)
The atoll sign in hepatic imaging has been described when a liver lesion shows a peripheral rim of high T2 signal intensity with the center of the lesion appearing isointense to the background of non-cirrhotic liver on T2WI mimicking an atoll. The peripheral rim shows hyperenhancement in the por...
Article
Serpent sign
The serpent sign, (also knowns as the snake sign), is a sign described in hydatid disease. The WHO classification (2001) or Gharbi classification (1985) of hydatid disease describe several stages on ultrasound 1.
During the active stage, the cyst is composed of three layers: the outer (pericyst...
Article
Porcelain gallbladder
Porcelain gallbladder refers to extensive calcium encrustation of the gallbladder wall. The term has been used to emphasize the blue discolouration and brittle consistency of the gallbladder wall at surgery but is often an incidental finding on multiple different imaging modalities.
Clinical p...
Article
Spoke wheel sign (focal nodular hyperplasia)
The spoke wheel sign is described in focal nodular hyperplasia (FNH) and describes the pattern of internal vasculature of FNHs seen on color Doppler ultrasound when multiple arteries radiate peripherally from the center of the lesion.
This sign was classically applied to the color/power Doppler...
Article
Wall-echo-shadow sign (ultrasound)
The wall-echo-shadow sign (also known as WES sign) is an ultrasonographic finding within the gallbladder fossa referring to the appearance of a "wall-echo-shadow":
a curvilinear hyperechogenic line representing the gallbladder wall
a thin hypoechoic space representing a small amount of bile
a...
Article
Nutmeg liver
A nutmeg liver appearance is due to a perfusion abnormality of the liver usually as result of hepatic venous congestion. When hepatic veins are congested, contrast is prevented from diffusing through the liver in a normal manner. This results in a mottled pattern of contrast enhancement in the a...
Article
Intrabiliary rupture of hepatic hydatid cyst
Intrabiliary rupture of hepatic hydatid cyst is a common complication associated with hepatic hydatid cysts. It is important to appreciate the direct and indirect signs of this condition.
Radiographic features
The radiological features of intrabiliary rupture of a hepatic hydatid cyst can be c...
Article
Rim sign (choledocholithiasis)
The rim sign of choledocholithiasis is a finding seen on contrast-enhanced CT and comprises a faint rim of increased density along the margin of a low-density area of calculus 1.
Article
Sonographic halo sign (disambiguation)
Sonographic halo sign can be useful in a number of situations:
hypoechoic halo sign (also known as target or bull's eye sign) in liver metastases: used in hepatobiliary imaging, is a concerning feature for malignant lesion if the lesion is a hyperechoic liver lesion 1,2
ultrasound halo in angi...
Article
Intrahepatic arterioportal shunt
Intrahepatic arterioportal shunts, also known as arterioportal fistulas, represent abnormal flow between the portal venous system and a hepatic arterial system within the liver. They can be a reversible cause of portal hypertension.
Clinical presentation
Clinical features will depend on the si...
Article
Starry sky appearance (ultrasound)
A starry sky appearance, also known as a centrilobular pattern 7, refers to a sonographic appearance of the liver parenchyma with bright echogenic dots throughout a background of decreased liver parenchymal echogenicity. Although usually associated with acute hepatitis, this sign has been found ...
Article
Phrygian cap
Phrygian caps are the most common congenital anatomic variant of the gallbladder. It denotes folding of the fundus back upon the gallbladder body and is asymptomatic with no pathological significance.
Radiographic findings
A Phrygian cap may be identified on ultrasound, multiphase CT/MRI, or c...
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