Diagnostic Ultrasound - Abdomen and Pelvis

Echogenic Bile
Diagnoses: Biliary System
Gallbladder Carcinoma
• Infiltrative mass with early invasion of adjacent liver
parenchyma
• Increased internal vascularity
• Regional nodal metastases
• Presence of gallstones
Parasitic Infection
• Ascariasis: Tubular or echogenic parallel lines within bile
duct or gallbladder; sonolucent center; active movement of
worm
• Hydatid: Daughter hydatid cysts are round and anechoic
within bile duct/gallbladder; mother cyst seen in liver
PATHOLOGY
General Features
• Etiology
○ Altered composition of bile
○ Decreased gallbladder motility and bile stasis
○ Predisposing factors
– Prolonged fasting/on total parenteral nutrition
– Pregnancy
– Rapid weight loss, post bariatric surgery
– Presence of critical illness
– Ceftriaxone or prolonged octreotide therapy
– Post bone marrow transplantation
– Liver transplantation
Gross Pathologic & Surgical Features
• Thick, crystallized bile sediment within normal-looking GB
• If longstanding disease ±superimposed inflammation
○ GB wall thickening with variable extent of chronic
inflammatory infiltrate
CLINICAL ISSUES
Presentation
• Most common signs/symptoms
○ Mostly asymptomatic
○ May have clinical symptoms when complications occur
– Stone formation
– Biliary colic
– Acute acalculous/calculous cholecystitis
– Pancreatitis
Demographics
• Epidemiology
○ Biliary sludge
– Similar epidemiology to cholelithiasis
– M < F
– More common in middle-aged, obese women
Natural History & Prognosis
• Biliary sludge
○ Approximately 50% of cases resolve spontaneously over
3-year period
○ 20% persist and remain asymptomatic
○ 5-15% develop gallstones
○ 10-15% become symptomatic
Treatment
• None required in vast majority of cases
• Elective cholecystectomy for complications
DIAGNOSTIC CHECKLIST
Consider
• Consider biliary sludge when mobile mid-/high-level echoes
without acoustic shadowing are seen in GB
Image Interpretation Pearls
• Sludge is precursor to stones
○ May cause acute pancreatitis
SELECTED REFERENCES
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87, ix, 2010
4. Stinton LM et al: Epidemiology of gallstones. Gastroenterol Clin North Am.
39(2):157-69, vii, 2010
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Am. 39(2):171-83, vii, 2010
6. Smith EA et al: Cross-sectional imaging of acute and chronic gallbladder
inflammatory disease. AJR Am J Roentgenol. 192(1):188-96, 2009
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therapy: role of CT in its diagnosis. Abdom Imaging. 33(6):652-3, 2008
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with liver cirrhosis. J Gastroenterol. 34(2):282-5, 1999
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ascariasis. Abdom Imaging. 23(1):60-6, 1998
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