Normal Gallbladder Appearance

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Key features:

• Pear-shaped, anechoic lumen (fluid filled) with clearly defined wall. 

• Wall thickness ≤ 3 mm when fully distended and in a fasted state. 

• Normal dimensions: about 7-10 cm in length, ~3-4 cm in transverse diameter in a fasted adult. 

• No intraluminal echogenic foci with shadowing, no wall irregularity or surrounding fluid.

Technique tips:

• Have the patient fast (often 6-12 h) so the gallbladder is distended and easily imaged. 

• Use the liver as an acoustic window (right upper quadrant, subcostal or intercostal) to reduce bowel gas interference. 

• Scan both long axis and short axis, and fan through to cover fundus, body, and neck.

🚨 Abnormal Appearances & Common Pathologies

Below are key abnormal findings, what they look like on ultrasound, and what they may represent.

1. Gallstones (Cholelithiasis)

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USG appearance:

• Hyperechoic (bright) foci within the lumen with posterior acoustic shadowing (regardless of stone composition). 

• Mobility of stones when patient position changes (if not impacted).

• A classic sign: the “WES sign” (Wall-Echo-Shadow) when gallbladder is packed with stones. 

Clinical note: Stones are a common finding in gallbladder ultrasound and may warrant further management depending on symptoms.

2. Gallbladder Sludge

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USG appearance:

• Low-level, non-shadowing echoes layering in dependent portion of lumen.

• May change with patient position but slower than free fluid.

• No significant posterior shadowing (distinguishing from stones).

Clinical note: Sludge may represent biliary stasis; may predispose to stones or cholecystitis.

3. Acute Cholecystitis

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USG appearance:

• Wall thickening > 3 mm. 

• Distended gallbladder (often > 10 cm length) with gallstones impacted in neck or cystic duct.

• Pericholecystic (surrounding) fluid or edema. 

• Positive sonographic Murphy’s sign: maximal pain when ultrasound probe presses over gallbladder. 

Clinical note: Combined with clinical findings (RUQ pain, fever, WBC), these features support acute cholecystitis diagnosis.

4. Chronic Cholecystitis / Gallbladder Wall Thickening

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USG appearance:

• Diffuse or focal wall thickening (may mimic inflammation). 

• Features of Adenomyomatosis of gallbladder: Rokitansky-Aschoff sinuses (small intramural cystic spaces) and “comet tail” artefact. 

Clinical note: Wall thickening may have multiple causes (inflammation, edema from systemic disease, neoplastic), so context is key.

5. Gallbladder Cancer / Mass-forming Lesions

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USG appearance:

• Focal intraluminal mass or thickened wall, often heterogeneous echotexture. 

• Irregular margins, possible calcifications, and may show invasion into liver parenchyma or adjacent structures.

• Large gallbladder polyps (>10 mm) may raise suspicion for malignancy. 

Clinical note: Suspicious features on ultrasound warrant further imaging (CT/MRI) and surgical consultation.

📝 Summary Table: Normal vs Abnormal Features