Ductus choledochus – function, structure & symptoms

Anatomy

Several small bile ducts can be found in the area of ​​the liver lobes. They join together with the right and left hepatic bile ducts (Ductus hepaticus). Together they form a short bile duct called the common hepatic duct. From the gallbladder, a duct opens into the common hepatic duct. Doctors refer to the further course of the combined bile duct as the ductus choledochus.The large bile duct is located above the duodenum. It leads to the pancreas , which in turn produces digestive juices . The transport of the juices from the pancreas takes place via the ductus pancreaticus, an excretory duct. The ductus choledochus runs behind the head of the pancreas. In addition, there is a close interdependence between it and the tissues of the gland.

The further course of the main bile duct leads past the duodenum in the direction of the intestinal wall. Since the ductus choledochus integrates into the intestinal wall , the mucosa folds up . This is called Plica longitudinalis duodeni. In its end area, it normally joins with the pancreatic duct. However, this union does not exist in every human being. If present, a bulge forms at the junction of the ducts, called the ampulla hepatopancreatica.

Together, the ductus choledochus and the pancreatic duct open into the intestinal tube of the duodenum. The large bile duct is equipped with smooth muscles . In addition, there is a layer of connective tissue composed of elastic and collagen fibers. The inner wall of the ductus choledochus is covered with mucous membrane. The glands in it release a secretion that ensures the lubricating properties inside the main bile duct. In this way, the outflow of bile works smoothly.

Function

The function of the large bile duct is to transport bile. This is how it gets from the liver or the gallbladder through the ductus choledochus towards the duodenum. There the bile is used for the process of digestion.

Just before entering the duodenum, the common bile duct is composed of smooth muscle. These are arranged like a ring. In addition, in the structure there are turns that resemble a spiral. This area is called Sphincter oddhi. His duties include opening and closing the entry point when the need arises.

If an active digestive process takes place in the duodenum, the sphincter oddhi opens. This allows the bile and digestive secretions to flow from the pancreas into the intestines. On the other hand, when there is a resting phase, the digestive juices collect within the main bile duct. Flow into the intestinal tube is prevented by the annular sphincter.

Diseases

• gallstones

• Choledocholithiasis

• jaundice

• Cholangitis

• autoimmune disease

• Bile duct atresia

The main bile duct can be affected by various diseases. This includes the formation of gallstones, which usually build up in the gallbladder. In some cases, however, these stones also migrate into the common bile duct.

If the large bile duct is blocked as a result, this is called choledocholithiasis. If the closure persists for a long time, there is a serious health problem. As the disease progresses, jaundice (icterus) and liver failure are possible.

In addition to the accumulation of gallstones, a tumor can also be responsible for the blockage of the main bile duct. External compression is also a possible cause. In the course of a gallbladder operation, a clamping or injury is conceivable, which results in a complete closure of the duct.Other possible diseases of the ductus choledochus are bacterial cholangitis or autoimmune diseases. A congenital malformation can appear in the form of atresia.