COMMON BILE DUCT EXPLORATIONS
The common bile duct is a tubular structure extending from the liver to the duodenum. Immediately before passing into the duodenum the common bile duct joins the main pancreatic duct in a short common channel known as the ampulla of Vater, which enters the second part of duodenum through the papilla, which is controlled by a complex muscle known as the sphincter of Oddi. The papilla and ampulla opens when the sphincter of Oddi relaxes, in response to secretion of two hormones, secretin and cholecystokinin (CCK) by cells in the duodenum when food is present in the duodenal lumen. Relaxation of sphincter of Oddi allows secretion of bile, together with pancreatic juice, into the duodenum to allow chemical digestion of constituents of the food in the duodenum. While the sphincter 0f Oddi is contracted and closed, bile, which is produced and secreted continuously by the liver into the bile ducts, diverts into the gallbladder where it is stored and concentrated between meals.
Most gallstones are formed in the gallbladder.
If gallstones move from the gallbladder into the bile duct, they can obstruct the common bile duct and cause jaundice, characterised by darkening of the urine, lightening of the colour of the faeces and yellowing of the skin and whites of the eyes. If biliary obstruction is associated with infection of the bile, a condition known as acute cholangitis, develops and can be associated with septicaemia, a severe, life-threatening blood infection.
If gallstones move from the gallbladder into the bile duct, they may also lodge in the ampulla of Vater and provoke another potentially life-threatening complication, acute pancreatitis.
What is common bile duct exploration?
Common bile duct exploration is a procedure done to remove stones from the common bile duct, whether or not they are obstructing the flow of bile to the duodenum.
In most cases, stones in the common bile duct are removed endoscopically by way of a relatively non-invasive procedure, endoscopic retrograde choledochoscopy with sphicterotomy (incision of the sphincter muscle to render it incompetent.
In certain circumstances, when endoscopic retrograde choledocoscopy and endoscopic sphincterotomy fails or for other reasons cannot be done, it may be necessary to surgically remove stones from the common bile duct.
One option to surgically remove stones from the common bile duct is as an extension to cholecystectomy, where a very fine choledochoscope is passed through the cystic duct into the common bile duct and a retrieval device is then passed to retrieve stones and extract them via the incision in the cystic duct.
If the surgeon cannot remove the stones via the cystic duct and the main bile duct is dilated, the surgeon may have to make an incision in the common bile duct, examine it with a choledochoscope and retrieve the stones and then close the incision in the duct with fine sutures. If there are numerous, large stones and the surgeon cannot be certain that all stones have been removed, it might be advisable to anastomose a loop of the small intestine to the opening in the bile duct.
Common Bile Duct Injury During Cholecystectomy
The most serious complication of cholecystectomy is a bile duct injury. This can result in leakage of bile into the abdomen or obstructive jaundice or both, and may be complicated by serious sepsis. If a bile duct injury is suspected the patient should be urgently referred to a specialist hepatobiliary surgeon.
A Primovist-enhanced abdominal MRI is required to establish whether there is an injury or not, and if there is, to delineate the anatomy of the injury and whether there are associated injuries to an hepatic artery and / or portal vein.
Less serious bile duct injuries are due to the cystic duct clip slipping off or damage to a small superficial duct in the bed of the gallbladder. These can usually be managed by endoscopic insertion of a biliary stent or by repeat laparoscopy to address the problem.
Injuries that involve transection or ligation of the common hepatic or right hepatic duct, with or without associated vascular injury require complex reconstruction, which can be extremely challenging surgery, usually involving isolating a segment of jejunum (proximal small intestine) and anastomosing this to the injured duct where it emerges from the liver.
