Gallbladder Polyps

This ultrasound demonstrates multiple non-shadowing, non-mobile, polypoid lesions measuring less than 7mm diameter. This appearance is typical of cholesterol polyps, representing the focal form of gallbladder cholesterolosis.
Cholesterolosis is a common idiopathic non-neoplastic condition, which may be focal (polyps) or diffuse (strawberry gallbladder). The diffuse form is not visible on imaging. Cholesterol polyps are typically 2-10mm in diameter, and are multiple in 80% of cases. Lesions larger than 10mm, with a broad base, or with irregular margins should raise the possibility of an alternative diagnosis.
Differential diagnoses include inflammatory polyps, adenoma (less than 5% of gallbladder polyps), focal adenomyomatosis, gallbladder adenocarcinoma, or metastases (especially melanoma).
Reference: Rumack CM, et al. Diagnostic Ultrasound Elsevier Mosby, 3rd edition, 2005.
Credit: Rocco Pozzolungo
Credit: Dr Laughlin Dawes
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