PRACTICAL APPROACHES TO BILIARY TRACT IMAGING

Richard Baron, M.D., University of Chicago

PRACTICAL APPROACHES TO BILIARY TRACT IMAGING

• Differentiating complicated gallbladder inflammation from neoplasm

• Detecting and staging cholangiocarcinoma

GB Carcinoma

Metastatic Melanoma

Staging GB Carcinoma

• Liver Involvement– Direct Invasion

• Regional Lymph Nodes– Pancreatico-duodenal– Node to the foramen of

Winslow• Peritoneal spread

• Distant hematogenousspread (liver, lung) uncommon

Gallbladder Adenomyomatosis

smooth muscle proliferationRokitansky-Aschoff sinusesSegmental, may be diffuse

can be difficult to differentiate from carcinoma

• Cholecystitis(often normal appearance)

Gallstoneswall thickeningpericholecystic halopericholecystic fluidpainful percussiongallbladder distension

• Complicated Cholecystitis

Marked wall thickeningLarger fluid collections

(assymetric)Gas in gallbladder lumen

or wallSloughed mucosa

GB Carcinoma vs. Complicated Cholecystitis?

Complicated Cholecystitis: sloughed mucosa

Complicated Cholecystitis: emphysematous

Complicated Cholecystitis vs. GB Carcinoma

• Symmetric wall thickening

• Halo around GB• Excessive fluid• Striated GB wall

• Assymetric wall thickening

• Replacement of GB lumen

• Liver invasion

Cholangiocarcinoma• Gross pathologic structure

– Annular, constricting– Infiltrative and expanding– Intraluminal, polypoid

• Underlying histologic stroma– Fibrous versus glandular stroma

• Locations– Intrahepatic, Proximal CBD, Distal

• Associations: PSC, Choledochal cysts; infections, chemical toxins

Key Clinical Settings for Chol-Ca:PSC (sclerosing cholangitis

Choledochal Cysts Fluke infestationTHICK SLAB THIN SLAB

Cholangiocarcinoma: Enhancement Characteristics

• Unenhanced CT: hypoattenuating• Arterial Phase CT/MR: minimally

enhancing (often peripheral rim enhancement )

• Portal Venous Phase CT/MR: continued enhancement (towards center)

• Equilibrium Phase: Delayed retention throughout if fibrous dominant stroma

Cholangiocarcinoma

Cholangiocarcinoma: Fibrous Stroma

Cholangiocarcinoma: Glandular Stroma

Spectrum of CholangiocarcinomaPathology

Fibrous Stroma Glandular Stroma

Mixed Stroma

Value of Delay Equilibrium Phase

Delay (mins)

6-10 11-15 16-20 21-25 26-30 31-36

Tumor enhancement 5 12 9 6 2 1No tumor enhancement 1 5 2 2 1 1

Total 6 17 11 8 3 2

CCA: Delay Contrast FindingsLacomis, Baron, Oliver, et al. Radiology 1997;203:998-104

Cholangiocarcinoma: duct wall thickening

Cholangiocarcinoma

Intraductal Papillary Tumor : Morphology

Lim JH , Baron R. ECR 2009

a. Polypoid tumor

b. Mucosal spreading growth

c. Castlike intraductal tumor

d. Cystic tumor

Clinical significance

• Treatment planning: resection

• Prediction of Prognosis: excellent

Papillary Cholangiocarcinoma

Cholangiocarcinoma:Superficial Spreading

Cholangiocarcinoma:Cast-Like

Mucin Producing Cholangiocarcinomawith cystic change

one two three four

Practical Biliary Tract Imaging: Converting Subtle to Obvious

• Optimize imaging techniques to optimize underlying pathologic features

• Understanding arterial, portal, and delay enhancement characteristics of biliarytumors

• Putting images in perspective with clinical setting