Imaging of Benign Biliary Tract Disease

Abstract

This review article discusses the most common benign biliary disorders and the various radiological findings on multiple modalities. A broad spectrum of diseases including various congenital disorders, infective and parasitic etiologies, immunological pathologies such as primary sclerosing cholangitis, and immunoglobulin G4-related sclerosing cholangitis are discussed along with obstructive diseases and ischemic cholangitis. The article emphasized the imaging differential diagnosis of the above lesions as well as clinical correlates those that are most relevant to radiologists. The article briefly touched upon management and intervention where relevant.

Keywords: IgG4-related sclerosing cholangitis; PSC; cholangiopathy; cholangitis.

Fig. 1

A 49-year-old male with jaundice. Ultrasonography (USG) images showing linear hypoechoic tubular structures (arrows) converging toward the hilum in the right ( A ) and left ( B ) lobes—dilated intrahepatic biliary radicles (IHBRs). ( C ) Minimum intensity projection (MinIP) computed tomography (CT) images clearly showing asymmetrically dilated IHBR.(arrows). Thick ( D ) and thin ( E , F ) slab magnetic resonance cholangiopancreatography (MRCP) showing aberrant IHBR drainage (arrows). Right posterior duct is clearly seen to drain into the cystic duct insertion on the thin three-dimensional (3D) MRCP sequence.

Fig. 2

Infant presented with clay colored stools and jaundice. Ultrasonography (USG) showing increased echogenicity anterior to portal vein division (arrow in A and calipers in B ). Abnormal gallbladder shape calipers in ( C ) and increased diameter of hepatic artery 2.2 mm (calipers) in ( D ). Findings suggestive of biliary atresia. Ultrasound cases and figures : Courtesy of Dr. Deeksha Rastogi, Department of Ultrasound, Sir Ganga Ram Hospital, Delhi, India.

Fig. 3

Young child presented with abdominal pain. Ultrasonography (USG) showed dilatation of common bile duct (CBD). Magnetic resonance cholangiopancreatography (MRCP) was performed for further evaluation. Coronal MRCP images ( A ) showing fusiform dilatation of the CBD suggestive of choledochal cyst with narrowing at lower end (arrowhead) and pancreaticobiliary maljunction with long common channel (arrow). ( B ) Excretion of hepatobiliary contrast into the choledochal cyst (arrow).

Fig. 4

A 16-year-old female with recurrent pain abdomen. Coronal thick slab magnetic resonance cholangiopancreatography (MRCP) ( A ) and axial T2-weighted (T2W) ( B ) images showing communicating dilated cysts (black arrowheads) consistent with findings of Caroli disease with multiple hypointense filling defects suggestive of calculi within (white arrows).

Fig. 5

A 55-year-old male with right hypochondrium pain and fever with chills. Coronal ( A ) and axial ( B ) computed tomography (CT) images showing dilated common bile duct (CBD) with tiny calculus at lower end (arrow in A ) with asymmetrically dilated intrahepatic biliary radicle (IHBR) showing periductal hypodensity at places and ductal thickening (arrowhead in B ). Axial CT images in arterial ( C ) phase showing dilated IHBR (arrowhead) with area of increased enhancement (arrow). Portal phase images show reduced attenuation around dilated IHBR in left lobe (arrowhead in D ) consistent with findings of cholangitis.

Fig. 6

Coronal magnetic resonance cholangiopancreatography (MRCP) images in a 45-year-old patient with extrahepatic portal vein obstruction (EHPVO) showing multiple extrinsic indentations on the right and left hepatic duct and the common bile duct (CBD), consistent with portal cavernoma cholangiopathy.

Fig. 7

A 45-year-old male, a known case of ulcerative colitis, presenting with fatigue and pruritus. Coronal magnetic resonance cholangiopancreatography (MRCP) images ( A , B ) showing cholangiographic findings of primary sclerosing cholangitis (PSC) with short segment strictures and irregularities shown by small white arrows. White arrowhead in ( A ) showing tiny diverticulae. Yellow arrowhead in ( B ) showing loss of acute angle at biliary branching. Note irregular outline of the biliary radicles and visualization of biliary radicles up to the periphery of liver. ( C ) Computed tomography (CT) with minimum intensity projection (MinIP) showing irregular dilatation of the bile ducts with small focal band-like strictures.

Fig. 8

A 55-year-old male with case of primary sclerosing cholangitis (PSC) on follow-up. Axial T2-weighted (T2W) images ( A ) showing increased signal (black arrowhead) in the hepatic parenchyma with a prominent caudate lobe. Note dilated biliary radicles (white arrowhead). Postcontrast images ( B ) in a different patient who presented with altered liver function tests (LFTs) reveal increased periductal enhancement (arrows) around the dilated biliary radicles.

Fig. 9

A 45-year-old male with pain abdomen and altered liver function test (LFT). Axial T2-weighted (T2W) ( A ) and T1W ( B ) images show typical fusiform enlargement of the pancreas (arrows) which shows increased T2 and decreased T1 signal. Coronal magnetic resonance cholangiopancreatography (MRCP) ( C ) images show narrowing at lower end of common bile duct (CBD) (arrowhead), with mildly dilated irregular main pancreatic duct (MPD). Findings are suggestive of autoimmune pancreatitis, confirmed on biopsy.

Fig. 10

Classification of immunoglobulin G4-related sclerosing cholangitis (IgG4SC) based on pattern of biliary tree involvement: ( A ) type 1 - lower common bile duct (CBD); ( B ) type 2A - intrahepatic with prestenotic dilatation; ( C ) type 2B - intrahepatic without prestenotic dilatation; ( D ) type 3 - Hilar and lower CBD involvement; ( E ) type 4 - Hilar involvement. Illustrations modified from Nakazawa et al. Digital Artwork by Dr. Varun Holla, Department of Radio Diagnosis, Sir Ganga Ram Hospital, Delhi, India.

Fig. 11

A 37-year-old female patient with immunoglobulin G4-related sclerosing cholangitis (IgG4SC). Axial ( A ) contrast-enhanced computed tomography (CECT) showing dilated intrahepatic biliary radicle (IHBR) (arrows) with thickened, enhancing walls. Coronal ( B ) CECT images showing thickened enhancing common bile duct (CBD) walls (arrows) with lumen seen despite the thickened walls.

Fig. 12

Coronal magnetic resonance cholangiopancreatography (MRCP) images ( A , B ) and T2-weighted (T2W) axial images ( C , D ) in a 38-year-old patient with jaundice showing markedly dilated biliary radicles showing hypointense filling defects suggestive of calculi in the dilated biliary radicles (white arrows) and in the dilated common bile duct (CBD) (white arrowheads). Findings are suggestive of recurrent pyogenic cholangitis.

Fig. 13

A young female with fever and eosinophilia. Outside computed tomography (CT) report of liver abscesses. Follow-up CT was done followed by ultrasonography (USG). Transverse USG ( A ) image showing irregular heteroechoic track with echogenic central and marginal areas. Axial CT ( B ) showing irregular branching tracks in the right lobe of liver extending up to the hepatic margins (tunnels and caves sign). Findings are suggestive of hepatic Fascioliasis. Partial resolution was seen on anti-helminthic treatment.

Fig. 14

Young male with jaundice, known human immunodeficiency virus (HIV) positive. Coronal three-dimensional (3D) magnetic resonance cholangiopancreatography (MRCP) thin slab image ( A ) showing narrowing at the lower end of the common bile duct (CBD) (arrow) with dilatation of the intrahepatic biliary radicle dilatation consistent with HIV cholangiopathy. Axial T2-weighted (T2W) images ( B ) showing circumferential thickening of lower end of the CBD.

Fig. 15

Coronal magnetic resonance cholangiopancreatography (MRCP) images in a 4-year-old male child with hepatic artery thrombosis showing multiple irregular nonanastomotic strictures on follow-up (arrows). Findings consistent with ischemic cholangiopathy.