Recent applicationS for ERCP in the management of Biliary Fistula

Abstract

Understanding the anatomy of the gallbladder and the extra hepatic biliary system is essential to all clinicians caring for patients with hepatobiliary disorders. Biliary anomalies are not uncommon and over 50% of all patients undergoing a biliary tract procedure will have either a ductal or an arterial anomaly. The failure to recognize such a congenital problem can result in significant per operative morbidity.

The extra hepatic biliary tract consists of the three hepatic ducts (right, left and common), the gallbladder and cystic duct and the common bile duct.

The biliary apparatus is a convergent system of canals that begins in the canaliculi, followed by the bile ducts, and ending with the common bile duct (coledochus).Bile secretion depends on the function of membrane transport systems in hepatocytes and cholangiocytes and on the structural and functional integrity of thebiliary tree. The hepatocytes, constituting the most abundant liver cell population (65%), generate the socalled primary bile in their canaliculi.

In the fasting state, approximately 80% of the bile secreted by the liver is stored in the gallbladder. This storage is made possible because of the remarkable absorptive capacity of the gallbladder, as the gallbladder mucosa has the greatest absorptive power per unit area of any structure in the body. It rapidly absorbs sodium, chloride, and water against significant concentration gradients, concentrating the bile as much as 10-fold and leading to a marked change in bile composition. This rapid absorption is one of the mechanisms that prevent a rise in pressure within the biliary system under normal circumstances. Gradual relaxation as well as emptying of the gallbladder during the fasting period also plays a role in maintaining a relatively low intraluminal pressure in the biliary tree.

Whether occurring as a consequence of calculous biliary tractdisease, trauma, neoplasm, or congenital anomalies, internalbiliary fistulae are uncommon. Estimates of incidence arecrude, gleaned only from many small series, usually with fewerthan 50 patients. If all types of internal biliary fistula areincluded, calculous biliary tract disease accounts for 90%;peptic ulcer disease, 6%; and neoplasm, trauma, parasitic infection,and congenital anomalies make up the remaining 4%.

External biliary fistulae are best considered according to thetype of previous intervention performed. The following are themore commonly associated surgical antecedents of fistulae. Fistulae After Cholecystostomy Biliary Fistulae After Invasive Radiologic Procedures Fistulae After Abdominal Operations: - Laparoscopic cholecystectomy. - Common duct exploration - Biliary-intestinal anastomosis - Surgery for hydatid disease.

ERCP is a direct contrast study of the pancreatico-biliary system. It is useful in the diagnosis and treatment of diseases involving the pancreas and bile ducts,such as stones, benign and malignant strictures, and developmental anomalies. It is superior to indirect cholangiography (oral or IV), especially in cases with obstructive jaundice, which leads to raised intrabiliary pressure and impaired biliary excretion of contrast. Moreover, intrahepatic bile duct pathologies can be demonstrated by ERCP using occlusion cholangiography. Pathology in the gallbladder and cystic duct abnormalities can also be visualized, although ERCP is not the best imaging study for gallbladder disease.

Endoscopic cannulation of the papilla of Vater was first reported in 1968 . However, it was really put on the map shortly afterwards by several Japanese groups, working with instrument manufacturers to develop appropriate Long side-viewing instruments . The technique (initially called ECPGa endoscopic Cholangiopancreatographyain Japan) spread throughout Europe in the early 1970s. Early efforts were much helped by a multinational workshop at the European Congress in Paris in 1972, organized by the Olympus company. ERCP rapidly became established worldwide as a valuable diagnostic technique, although doubts were expressed in the USA about its feasibility and role , and the potential for serious complications soon became clear . ERCP was given a tremendous boost by the development of its therapeutic applications, notably biliary sphincterotomy in the mid-1970s and biliary stenting 5 years later.