Diagnostic Ultrasound - Abdomen and Pelvis

Caroli Disease
Diagnoses: Liver
• Bile duct wall thickening and enhancement
• Extrahepatic bile duct dilatationdue to obstructing stones
or tumor
Biliary Hamartoma
• Variant of fibropolycystic disease
• Ductal plate malformation: Involves small-sized IHBDs
• Innumerable subcentimeter cysts/nodules in liver
• Do not communicate with biliary tree
• Variable enhancement
○ Completely cystic: No enhancement
○ Solid elements in walls: Enhance and become isodense
with liver
PATHOLOGY
General Features
• Etiology
○ Incomplete remodeling of ductal plate leading to
persistence of embryonic biliary ductal structures
○ Varying spectrum of adult and juvenile manifestations of
ductal malformations
– Caroli disease: Malformation of large-sized ducts
(more common in adults)
– Caroli syndrome: Malformation of large- and smallsized
ducts (more common in children)
□ Ductal plate anomaly of small-sized ducts leads to
hepatic fibrosis
• Genetics
○ Inherited as an autosomal recessive pattern
• Associated abnormalities
○ Medullary sponge kidney (renal tubular ectasia)
○ Autosomal recessive polycystic kidney disease (ARPKD);
rarely autosomal dominant polycystic kidney disease
(ADPKD)
○ Hepatic fibrosis, biliary hamartoma, choledochal cysts
Gross Pathologic & Surgical Features
• Saccular dilatations of large intrahepatic bile ducts
• Diffuse, lobar or segmental distribution
Microscopic Features
• Caroli disease
○ Segmental saccular dilatation of large IHBDs
○ Dilated ducts lined by hyperplastic or ulcerated biliary
epithelium
○ Normal hepatic parenchyma
• Caroli syndrome
○ Segmental saccular dilatation of IHBDs
○ Proliferation of bile ductules and fibrosis
○ Hypoplastic portal vein branches
CLINICAL ISSUES
Presentation
• Most common signs/symptoms
○ Usually asymptomatic in early state
○ Symptoms/signs related to cholangitis
– Fever, abdominal pain, jaundice
○ Symptoms/signs related to hepatic fibrosis
– Hepatomegaly
– Portal hypertension and its sequelae (splenomegaly,
varices, etc.)
• Other signs/symptoms
○ Enlarged kidneys due to associated ARPKD
• Lab data:May show elevated liver enzymes & bilirubin levels
• Diagnosis based on imaging; biopsy is rarely indicated
Demographics
• Age
○ Condition present at birth, but can be asymptomatic for
years
– 80% become symptomatic before age of 30
○ Caroli disease
– Symptoms usually present in 2nd & 3rd decades
○ Caroli syndrome
– Symptoms can present earlier during infancy or
childhood
• Gender: M:F = 1:1
• Epidemiology: Rare disease
Natural History & Prognosis
• Complications
○ Recurrent cholangitis,biliary stone formation,hepatic
abscesses
○ Secondary biliary cirrhosis;portal hypertension and its
sequelae
○ Cholangiocarcinoma in 7% of patients
• Prognosis
○ Depends on severity of disease and coexisting renal
disease
○ Long-term prognosis for Caroli disease is usually poor
Treatment
• Supportive therapy for cholangitis
• Decompression of biliary tract: External drainage or biliaryenteric
anastomoses
• Surgery
○ Localized to lobe or segment: Hepatic lobectomy or
segmentectomy
○ Diffuse disease: Liver transplantation
DIAGNOSTIC CHECKLIST
Consider
• Rule out other liver diseases, which have hepatic cysts
±dilated bile ducts
Image Interpretation Pearls
• US/CT/MR: "Central dot" sign
• ERCP/MRCP: Saccular dilatations show communication with
IHBD, which differentiates Caroli from other variants of
fibropolycystic disease
SELECTED REFERENCES
1. Venkatanarasimha N et al: Imaging features of ductal plate malformations in
adults. Clin Radiol. 66(11):1086-93, 2011
2. Levy AD et al: Caroli's disease: radiologic spectrum with pathologic
correlation. AJR Am J Roentgenol. 179(4):1053-7, 2002
3. Gorka W et al: Value of Doppler sonography in the assessment of patients
with Caroli's disease. J Clin Ultrasound. 26(6):283-7, 1998
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