Bile duct injury during cholecystectomy is a serious surgical complication that can have devastating consequences, including a significant risk of early death. Bile duct injury also has a major effect on healthcare costs, since injured patients frequently need prolonged and repeated hospital stay, multiple re-interventions, and long sick leave. In anatomically difficult cholecystectomies, which probably carry a high risk of bile duct injury, it is difficult to perform a successful intraoperative cholangiogram, thus reducing the cholangiography rate in cholecystectomies prone to bile duct injury. Törnqvist et al. recently reported a cumulative incidence of bile duct injury during laparoscopic cholecystectomy of 1.5 %. A majority of bile duct injuries detected postoperatively were discovered as bile leakage, either from the cystic duct (46 %) or from small ducts in the liver bed (18 %), whereas only a small number (2 %) of the injuries with delayed detection were classified as severe.

Biliary complications are more common after laparoscopic than after open cholecystectomy and include bile duct damage, biliary obstruction, and dropped stones. Injury to the bile ducts often goes unrecognized at the time of surgery. There should be a high level of suspicion when patients are referred with symptoms of abdominal pain, sepsis, or jaundice soon after laparoscopic cholecystectomy.

Initial assessment in patients with suspected bile duct injury is usually with ultrasound or CT, which may show free fluid or fluid collection in the right upper quadrant. Hepatobiliary scintigraphy (HIDA scan) is a less commonly used noninvasive method of evaluating patients with suspected bile duct injury. Major disadvantage is that HIDA scan is a functional exam and another imaging study may be needed to further evaluate the findings. ERCP is invasive and useful in patients in whom there is a strong suspicion of bile duct injury, with the possibility to treat the leak using internal stent. Open surgery is the main alternative to ERCP in cases of persistent large leaks.

MR imaging and MR cholangiopancreatography (MRCP) either using gadobenate or gadoxetate can be used to assess any suspected bile leakage. The accuracy of liver-specific gadolinium-based contrast agent for the detection of bile leak varies approximately 80 %. Typically, MRI and MRCP images will show nonspecific findings of ascites, which could be traced into the gallbladder fossa in most cases. Specific finding includes the increased signal intensity of the ascites on the hepatobiliary phase (HBP) fat-suppressed 3D gradient-echo T1-weighted images (20 min after gadoxetate and 1–2 h after gadobenate injection). These images should be compared with the pre-contrast fat-suppressed T1-weighted images. The increased T1 signal intensity is due to the contrast that leaks from the injured bile duct into the peritoneal cavity (Figs. 142.1 and 142.2). Normally, the liver-specific contrast agents show uptake in the liver and are excreted via the bile ducts into the bowel. Although gadobenate can be used, gadoxetate is favorable to assess suspected bile leakage due to its shorter 20-min HBP and larger amount (50 %) of biliary excretion.

Caroli’s disease is an autosomal recessive disorder comprised of communicating cavernous ectasia of the intrahepatic bile ducts. The disease is considered among the ductal plate abnormalities that occur at different levels in the developing biliary tree, leading to several clinicopathologic entities. The abnormalities can be present at the level of the large ducts (Caroli’s disease), small ducts (congenital hepatic fibrosis), or both (congenital hepatic fibrosis with Caroli’s disease, also called Caroli’s syndrome). Clinically, the entity is divided as follows: type I (Caroli’s disease) that is rare and is characterized by recurrent episodes of cholangitis and type II (Caroli’s disease associated with fibrosis) that is more frequent and is characterized by fibrosis and portal hypertension. Ultrasound and CT can show the multiple intrahepatic cysts in close relation to the biliary system. They fail however to actually demonstrate the communication between the two, which is important in distinguishing Caroli’s disease from polycystic liver disease or multiple abscesses. Also at ERCP and cholangiography, it may be difficult to get an overview of the entire biliary tree. MR imaging provides a better view of the biliary system as well as the parenchyma noninvasively.

Caroli’s disease is a form of congenital (likely, autosomal recessive inheritance) dilatation of intrahepatic bile ducts. It is usually manifested in childhood. The association of Caroli’s disease with extrahepatic bile duct dilatation may be present in up to 21 % of patients. Repeated bouts of cholangitis, stone formation, and stone passage may explain extrahepatic duct dilatation in some patients with Caroli’s disease or Caroli’s syndrome. Caroli’s disease may also occur in association with cysts in the kidneys. In such cases, Caroli’s disease should be distinguished from adult polycystic liver and kidney disease. Cholangiocarcinoma is a well-known complication of long-standing Caroli’s disease. Since the original description by Caroli et al. in 1958, a number of case reports and small series have appeared in the radiology literature describing the cholangiographic, sonographic, CT, and MR imaging features of the disease.

Cholelithiasis (gallstones) remains one of the most common medical problems leading to surgical intervention. Gallstones represent a polygenic disorder that affects more than 30,000,000 (10 %) Americans and results in more than 750,000 cholecystectomies in the USA annually. Risk factors include age, gender, race, parity, obesity, and diabetes. A family history of gallstones also has been identified as a risk factor suggesting that genetics play a role in gallstone formation. Genetic factors are responsible in at least 30 % of symptomatic gallstones. Approximately three-fourths of the patients with gallstones in the USA have stones that are composed primarily of cholesterol. The pathogenesis of cholesterol gallstones is known to be multifactorial. Approximately 35 % of patients with gallstones developed complications or recurrent symptoms leading to cholecystectomy. The sensitivity of abdominal US for cholelithiasis or gallstones is in excess of 95 %. Sensitivities of conventional CT in the setting of suspected choledocholithiasis range from 76 to 90 %. Because up to 15–25 % of patients with acute calculous cholecystitis have choledocholithiasis, MRCP may play a role in gallstone disease, particularly in patients with gallstone pancreatitis and cystic duct and gallbladder neck calculi.

Choledocholithiasis (bile duct stones) has been reported to occur in up to 15 % of patients with symptomatic gallstones. The sensitivities of ultrasound for common duct stones range from 18 to 74 %. This variable sensitivity is related in part to the operator-dependent nature of ultrasound and the obscuration of stones by bowel gas. Many centers still perform diagnostic endoscopic retrograde cholangiopancreatography (ERCP) in patients with suspected bile duct stones. Recent data shows that ERCP is associated with major complications in 4.0 % of the cases, including pancreatitis (1.3 %), cholangitis (0.87 %), hemorrhage (0.76 %), duodenal perforation (0.58 %), and others (0.51 %). Diagnostic ERCP shows major complication rate of 1.38 % and a death rate of 0.21 %, whereas therapeutic ERCP shows significantly higher rate for major complications (5.4 %) and deaths (0.49 %). Sensitivity and specificity of MRCP for choledocholithiasis exceed 90 %. Negative predictive values of MRCP are also quite high, ranging from 96 to 100 %. Thus, perhaps more important than the ability of MRCP to detect common bile duct stones is its ability to exclude stones because the absence of common bile duct stones at MRCP may result in avoidance of diagnostic ERCP along with its potential complications. Excellent performance of MRCP can result in the avoidance of ERCP in 52 and 80 % of patients with high and low risk for common bile duct stones, respectively.

Primary carcinoma of the gallbladder is the sixth most common gastrointestinal malignancy, following cancer of the colon, pancreas, stomach, liver, and esophagus. Annually, about 7,000 new cases are diagnosed. Risk factor may include chronic Salmonella typhi infection; exposure to chemicals used in the rubber, automobile, wood finishing, and metal fabricating industries; and cholelithiasis. The symptoms at presentation are vague and are most often related to adjacent organ invasion. Therefore, despite advances in cross-sectional imaging, early-stage tumors are not often encountered. The vast majority of gallbladder carcinomas are adenocarcinomas. Because most patients present with advanced disease, the prognosis is poor, with a reported 5-year survival rate of less than 5 % in most large series. Imaging studies may reveal a mass replacing the normal gallbladder (up to 65 %), diffuse or focal thickening of the gallbladder wall (up to 30 %), or a polypoid mass within the gallbladder lumen (up to 25 %). The liver may be involved by direct contiguous spread in up to 90 % of cases, followed by the colon, duodenum, and pancreas.