Benign Biliary Strictures

Abstract

Differentiating benign and malignant biliary strictures is a challenging and important clinical scenario. The typical presentation is indolent and involves elevation of liver enzymes, constitutional symptoms, and obstructive jaundice with or without superimposed or recurrent cholangitis. While overall the most common causes of biliary strictures are malignant, including cholangiocarcinoma and pancreatic adenocarcinoma, benign strictures encompass a wide spectrum of etiologies including iatrogenic, autoimmune, infectious, inflammatory, and congenital. Imaging plays a crucial role in evaluating strictures, characterizing their extent, and providing clues to the ultimate source of biliary obstruction. While ultrasound is a good screening tool for biliary ductal dilatation, it is limited by a poor negative predictive value. Magnetic resonance cholangiopancreatography is more than 95% sensitive and specific for detecting biliary strictures with the benefit of precise anatomic localization. Other commonly employed imaging modalities include endoscopic retrograde cholangiopancreatography with endoscopic ultrasound, contrast-enhanced CT, and cholangiography. First-line treatment of benign biliary strictures is endoscopic dilation and stenting. In patients with anatomy that precludes endoscopic cannulation, percutaneous biliary drain insertion and balloon dilation is preferred.

Keywords: benign stricture; biliary strictures; interventional radiology; percutaneous biliary drainage; percutaneous transhepatic cholangiogram.

Fig. 1

Patient with a history of liver transplant. (a) Endoscopic retrograde cholangiopancreatography image shows a stricture of the common bile duct at the surgical anastomosis (arrow) with mild proximal ductal dilatation. A 10F 15-cm stent was placed across the stricture. (b) Coronal T2-weighted magnetic resonance cholangiopancreatography image shows a linear band at the level of the anastomosis (arrow) suspicious for stricture with mild intrahepatic and extrahepatic biliary dilatation.

Fig. 2

Patient with primary sclerosing cholangitis. (a) Ultrasound with color Doppler shows mild intrahepatic biliary ductal dilatation (arrow). (b) Image obtained during endoscopic retrograde cholangiopancreatography shows a short-segment stricture of the common bile duct near the hilum with alternating segments of mild biliary dilatation and intrahepatic strictures. (c and d) Coronal T2-weighted magnetic resonance cholangiopancreatography images show a “bead on a string” appearance of the intrahepatic bile ducts.

Fig. 3

A second patient with primary sclerosing cholangitis. (a) Coronal T2-weighted magnetic resonance cholangiopancreatography image reveals the “pruned tree” appearance of abruptly tapering distal intrahepatic bile ducts and mild intrahepatic biliary dilatation. (b) Image obtained during endoscopic retrograde cholangiopancreatography shows multifocal short-segment stenoses at the biliary bifurcation with a dominant hilar stricture and mild upstream dilatation. The patient was treated with sphincterotomy and balloon dilation.

Fig. 4

Patient with autoimmune sclerosing cholangitis and pancreatitis. (a) Image obtained during endoscopic retrograde cholangiopancreatography shows a 10-mm segmental narrowing of the distal common bile duct (arrow) with mild upstream dilatation. Multifocal strictures of the pancreatic duct with evidence of pancreatitis were also noted. (b) T2-weighted coronal magnetic resonance cholangiopancreatography image shows a dilated common bile duct which smoothly tapers distally (arrow) with a focal short-segment stricture of the intrapancreatic bile duct.

Fig. 5

Patient with IgG4-related autoimmune sclerosing cholangitis and pancreatitis. (a) T1-weighted axial postcontrast magnetic resonance cholangiopancreatography (MRCP) image shows subtle linear peripheral enhancement of the pancreatic body (arrow). (b) Coronal T2-weighted MRCP image shows intrahepatic and extrahepatic biliary ductal dilatation with an abrupt stenosis of the common bile duct at the level of the pancreatic head (arrow).

Fig. 6

Patient with pathology-proven recurrent pyogenic cholangitis and periportal fibrosis status posthepatic lobectomy. (a) Coronal T2-weighted magnetic resonance cholangiopancreatography (MRCP) image shows marked left lobar intrahepatic biliary ductal dilatation with multifocal short-segment strictures and stones (arrow). (b) Axial T2-weighted MRCP image shows multiple intrahepatic stones (arrow).