Diagnostic Ultrasound - Abdomen and Pelvis

Recurrent Pyogenic Cholangitis
TERMINOLOGY
Abbreviations
• Recurrent pyogenic cholangitis (RPC)
Synonyms
• Hepatolithiasis, oriental cholangiohepatitis
Definitions
• Recurrent episodes of acute pyogenic cholangitis with
intra- and extrahepatic biliary pigment stones
IMAGING
General Features
• Best diagnostic clue
○ Intra- and extrahepatic biliary pigmented stones within
dilated biliary ducts
• Location
○ Lateral segment of left lobe and posterior segment of
right lobe are more commonly involved
Ultrasonographic Findings
• Grayscale ultrasound
○ Commonly used for screening and monitoring disease
○ Findings depend on stage of disease and presence of any
associated complication
○ Early disease without biliary sepsis
– Dilated intrahepatic and extrahepatic bile ducts
– Presence of echogenic sludge/stones ±posterior
acoustic shadowing
– May appear as multiple echogenic masses in
serpiginous configuration along portal triads if
stones/sludge fills dilated ducts
○ Early disease with active biliary sepsis
– Periportal hypo-/hyperechogenicity due to periductal
inflammation
– Biliary ductal thickening related to edematous
inflammation
– Floating echoes within dilated ducts due to
inflammatory debris
– Multiple cholangitic abscesses appear as small cystic
cavities with internal debris
○ Late-stage disease
– Severe atrophy of affected lobe/segment
– Crowded, stone-filled ducts may appear as single
heterogeneous mass
– Development of biliary cirrhosis with portal
hypertension
• Color Doppler
○ No flow within dilated bile ducts
Radiographic Findings
• Cholangiography
○ Intrahepatic or extrahepatic duct stones as filling defects
○ Dilatation of extrahepatic and central intrahepatic ducts
○ Ductal rigidity and straightening,right-angle branching
pattern
○ Decreased arborization and rapid tapering of peripheral
intrahepatic duct
○ Ductal luminal irregularity and focal strictures
CT Findings
• CECT
○ Dilated intra- and extrahepatic biliary ducts within
involved segments
○ Biliary stones may be high attenuation or isodense to
liver
○ May be associated with low-attenuation pyogenic liver
abscesses, fatty liver atrophy of segments with chronic
biliary obstruction
MR Findings
• T1WI
○ Intrahepatic stones may be hyperintense
• T2WI
○ Hyperintense bile within obstructed ducts and
hypointense ductal stones
• MRCP
○ Dilated intra- and extrahepatic ducts with filling defects
representing stones
○ Ductal rigidity and straightening,rapid tapering of
peripheral intrahepatic duct
○ Findings similar to direct cholangiography but
advantageous in case of missing duct by severe stricture
Nuclear Medicine Findings
• Hepatobiliary scintigraphy
○ Delay in tracer excretion and drainage into biliary tree
○ Tracer retention within dilated intrahepatic ducts of
affected lobe/segment
Imaging Recommendations
• Best imaging tool
○ Ultrasound is best initial imaging modality for disease
detection, assessment of complication, and as guidance
for percutaneous drainage
○ CECT/MRCP may help anatomical delineation in
– Patients with small, atrophic liver, which is
suboptimally assessed by US
– Patients contemplating surgical treatment
• Protocol advice
○ Scan patient in different positions & imaging planes to
detect subtle ductal changes & small, intrahepatic stones
in early disease
○ Assessment of small atrophic liver may be technically
difficult; CT/MRCP may allow better delineation
DIFFERENTIAL DIAGNOSIS
Ascending Cholangitis
• Obstruction of common bile duct (CBD) with proportional
dilatation of intra- and extrahepatic ducts
• Enhanced wall thickening of inflamed bile ducts
• Periportal hypo- or hyperechogenicity due to periductal
inflammation
Primary Sclerosing Cholangitis
• Multiple areas of intrahepatic strictures alternating with
biliary dilatation resulting in beaded appearance
• Ductal dilatation is usually mild due to periductal fibrosis
• Associated with inflammatory bowel disease (particularly
ulcerative colitis)
Diagnoses: Biliary System
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