Diagnostic Ultrasound - Abdomen and Pelvis

Choledocholithiasis
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Diagnoses: Biliary System
DIFFERENTIAL DIAGNOSIS
Cholangiocarcinoma
• Intrahepatic or extrahepatic infiltrative or irregular mass
• Soft tissue growth within ductal lumen
• Obstruction and dilatation of CBD and IHBD
• Regional nodal and liver metastases
Biliary Parasitic Infestation
• Most common infestation: Ascaris, Clonorchis
• Parallel echogenic tubular structures with sonolucent
center within bile duct
• Active movement of parasite
• Lack of posterior acoustic shadowing
Ampullary Mass
• Hypodense mass in head of pancreas or ampulla
• Ill-defined infiltrative margin
• "Double duct" sign
○ Obstruction and dilatation of pancreatic duct and CBD
• Vascular encasement
• Contiguous organ invasion/regional nodal metastases may
be seen
Ascending Cholangitis
• Clinical information suggesting biliary sepsis
• Ductal wall thickening is hallmark in appropriate clinical
setting
• Usually due to superinfection of biliary obstruction by CBD
stone, less likely from strictures
• Can be associated with echogenic biliary sludge within
ducts
Recurrent Pyogenic Cholangitis
• Historically in patients of East Asian demographic
• Recurrent bouts of cholangitis
• Strong association with parasites, such as Ascaris
lumbricoides and Clonorchis sinensis
• Pigmented stones &/or sludge within dilated intrahepatic
and extrahepatic bile ducts
• Disproportionate increased dilation of central and
extrahepatic bile ducts with stricturing and stenosis of
peripheral ducts
PATHOLOGY
General Features
• Etiology
○ Primary choledocholithiasis: De novo formation of
stones within bile ducts, precipitated by bile stasis and
infection
○ Secondary choledocholithiasis: Gallstones migrate into
CBD, most common
• Associated abnormalities
○ Gallstones
– 5-20% of patients with gallstones will have
choledocholithiasis at time of cholecystectomy
○ Dilated ducts
CLINICAL ISSUES
Presentation
• Most common signs/symptoms
○ RUQ pain, pruritus, jaundice
○ May be asymptomatic
• Other signs/symptoms
○ May present with complication: Acute cholangitis, acute
pancreatitis
• Clinical profile
○ "Fat, fertile, 40, female": Overweight, middle-aged
female with history of acute or intermittent RUQ pain
and jaundice
• Lab data
○ Increased alkaline phosphatase and direct bilirubin
Demographics
• Age
○ Usually adults; can be seen in any age group
• Gender
○ F > M
Natural History & Prognosis
• Small stones may pass spontaneously without causing any
symptoms
• Complications: Cholangitis, obstructive jaundice,
pancreatitis, secondary biliary cirrhosis
Treatment
• ERCP: Preoperative, intraoperative, or postoperative
• Intraoperative common bile duct exploration: Open versus
laparoscopic
• Other lithotripsy: Extracorporeal shock wave,
electrohydraulic, laser
DIAGNOSTIC CHECKLIST
Consider
• Rule out other causes of "CBD obstruction"
Image Interpretation Pearls
• Echogenic filling defects casting posterior acoustic
shadowing associated with dilatation of CBD/intrahepatic
bile ducts
SELECTED REFERENCES
1. Costi R et al: Diagnosis and management of choledocholithiasis in the
golden age of imaging, endoscopy and laparoscopy. World J Gastroenterol.
20(37):13382-401, 2014
2. Stinton LM et al: Epidemiology of gallbladder disease: cholelithiasis and
cancer. Gut Liver. 6(2):172-87, 2012
3. O'Connor OJ et al: Imaging of biliary tract disease. AJR Am J Roentgenol.
197(4):W551-8, 2011
4. Yeh BM et al: MR imaging and CT of the biliary tract. Radiographics.
29(6):1669-88, 2009
5. Rubens DJ. Ultrasound imaging of the biliary tract. Ultrasound Clinics.
2(3):391–413, 2007
6. Caddy GR et al: Gallstone disease: Symptoms, diagnosis and endoscopic
management of common bile duct stones. Best Pract Res Clin
Gastroenterol. 20(6):1085-101, 2006
7. Freitas ML et al: Choledocholithiasis: evolving standards for diagnosis and
management. World J Gastroenterol. 12(20):3162-7, 2006
8. Tazuma S: Gallstone disease: Epidemiology, pathogenesis, and classification
of biliary stones (common bile duct and intrahepatic). Best Pract Res Clin
Gastroenterol. 20(6):1075-83, 2006
9. Hanbidge AE et al: From the RSNA refresher courses: imaging evaluation for
acute pain in the right upper quadrant. Radiographics. 24(4):1117-35, 2004