Biliary system

Biliary System

The biliary system is a complex network of organs and ducts that are responsible for the production, storage, and transportation of bile. Bile is a digestive fluid that is essential for the digestion and absorption of fats in the small intestine. The biliary system includes the liver, gallbladder, and bile ducts.

Anatomy of the Biliary System

Liver

The liver is the largest internal organ and plays a crucial role in the production of bile. Hepatocytes, the liver cells, secrete bile into small channels called bile canaliculi. These canaliculi merge to form larger bile ducts within the liver, eventually forming the right and left hepatic ducts.

Gallbladder

The gallbladder is a small, pear-shaped organ located beneath the liver. It stores and concentrates bile produced by the liver. When food, especially fatty food, enters the small intestine, the gallbladder contracts and releases bile into the duodenum through the bile ducts.

Bile Ducts

The bile ducts are a series of channels that transport bile from the liver and gallbladder to the duodenum. The right and left hepatic ducts join to form the common hepatic duct. The cystic duct from the gallbladder joins the common hepatic duct to form the common bile duct. The common bile duct then joins the pancreatic duct to form the ampulla of Vater, which opens into the duodenum.

Function of the Biliary System

The primary function of the biliary system is to facilitate the digestion and absorption of lipids. Bile contains bile acids, cholesterol, phospholipids, and bilirubin. Bile acids are critical for emulsifying fats, making them accessible to digestive enzymes.

Clinical Significance

Gallstones

Gallstones are solid particles that form from bile cholesterol and bilirubin in the gallbladder. They can cause blockages in the bile ducts, leading to pain, infection, or inflammation known as cholecystitis.

Biliary Atresia

Biliary atresia is a congenital condition in which the bile ducts are abnormally narrow, blocked, or absent. It can lead to liver damage and requires surgical intervention.

Cholangiocarcinoma

Cholangiocarcinoma is a cancer of the bile duct system. It is a rare but aggressive form of cancer that requires early detection and treatment.

Diagnostic and Therapeutic Procedures

Endoscopic Retrograde Cholangiopancreatography (ERCP)

Endoscopic retrograde cholangiopancreatography (ERCP) is a procedure used to diagnose and treat conditions of the bile ducts. It combines endoscopy and fluoroscopy to visualize the bile and pancreatic ducts.

Magnetic Resonance Cholangiopancreatography (MRCP)

Magnetic resonance cholangiopancreatography (MRCP) is a non-invasive imaging technique that uses magnetic resonance imaging (MRI) to visualize the biliary and pancreatic ducts.

See Also

• Digestive system
• Liver function tests
• Pancreas

References

• "Biliary System Anatomy and Function." Medical Journal of Gastroenterology, vol. 12, no. 3, 2023, pp. 123-130.
• Smith, J. "Gallstones and Biliary Disorders." Clinical Gastroenterology, 2022.