KEY FACTS
Imaging
- •
Highly reflective, mobile and gravity-dependent intraluminal structures with posterior clean shadowing
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Variable size; stones < 5 mm may not shadow
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Contracted gallbladder (GB) full of stones may not exhibit mobility and may be mistaken for duodenal bulb
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Wall-echo-shadow (WES) sign: 2 echogenic, curvilinear lines separated by sonolucent line
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Always evaluate for biliary dilatation and signs of cholecystitis, cholangitis, or pancreatitis
Top Differential Diagnoses
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GB polyp
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GB sludge
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Focal adenomyomatosis
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GB carcinoma
Pathology
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80% are cholesterol stones, containing > 50% cholesterol
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20% are pigmented stones, containing cholesterol and calcium carbonate/bilirubinate
Clinical Issues
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10-15% of population; peak: 5th-6th decade, increasing with age; M:F = 1:3
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Right upper quadrant pain/discomfort after fatty meal
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Asymptomatic, incidental finding on imaging
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Complications including acute or chronic cholecystitis, choledocholithiasis, cholangitis, pancreatitis, gallstone ileus, or cancer of GB
Scanning Tips
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Patients should fast 6-8 hours
- •
Optimize parameters to maximize visualization of posterior acoustic shadowing from small stones
- •
Examine patient in supine and left decubitus/oblique position to demonstrate mobility of gallstone; consider erect or semiprone positions
- •
Twinkling artifact should not be mistaken for flow
and distal bile duct 
.
in the GB neck. Note acoustic shadowing 
and mild GB wall thickening 
.
with a layer of dependent sludge 
.
, echo 
, and shadow 
, which together form the WES sign.
in the GB. Mild wall thickening 
and pericholecystic 
fluid were secondary to pancreatitis.
with acoustic shadowing 
. Note the sludge level 
but no wall thickening.
. The GB wall was normal.
in the neck with an edematous, thick wall 
. The Murphy sign was positive.
