What does biliary mean?

What Does Biliary Mean?

Biliary refers to the system of structures and ducts that create, transport, store, and release bile, including the gallbladder, bile ducts, and associated structures. 1

Anatomy of the Biliary System

The biliary system consists of several key components:

• Bile ducts: A network of tubes that transport bile from the liver to the small intestine

  • Intrahepatic bile ducts: Located within the liver
  • Extrahepatic bile ducts: Located outside the liver, including:
    • Common hepatic duct
    • Common bile duct
    • Cystic duct (connects gallbladder to bile duct system) 2

• Gallbladder: A pear-shaped organ that stores and concentrates bile

• Sphincter of Oddi: A muscular valve that controls the flow of bile into the small intestine 3

Functions of the Biliary System

The biliary system serves several important physiological functions:

• Production and transport of bile from the liver to the small intestine
• Storage and concentration of bile in the gallbladder
• Release of bile into the digestive tract to aid in fat digestion and absorption
• Elimination of waste products through bile

Clinical Significance

Understanding the biliary system is important because:

1. Biliary complications are common, occurring in 10-25% of liver transplant patients 1

2. Types of biliary complications include:

   • Bile leaks and bilomas
   • Anastomotic strictures
   • Diffuse biliary strictures
   • Sludge and stones
   • Sphincter of Oddi dysfunction
   • Cystic duct mucoceles 1

3. Biliary diseases include:

   • Gallstones (cholelithiasis)
   • Biliary tract cancers (cholangiocarcinoma, gallbladder cancer) 1
   • Primary biliary cirrhosis (autoimmune disease affecting intrahepatic bile ducts) 4
   • Biliary dyskinesia (motility disorder affecting gallbladder and sphincter of Oddi) 3
   • Caroli disease (congenital dilatation of intrahepatic bile ducts) 1

4. Diagnostic imaging of the biliary system often includes:

   • Ultrasound (first-line for gallbladder imaging)
   • CT and MRI for more detailed evaluation
   • Magnetic resonance cholangiopancreatography (MRCP) for optimal visualization of the biliary tree 1

Terminology Related to Biliary Structures

• Peribiliary: Around or surrounding the bile ducts 1, 5
• Intrahepatic: Within the liver 1
• Extrahepatic: Outside the liver 1
• Cholestatic: Relating to reduced or blocked bile flow 4

Understanding the biliary system is essential for diagnosing and treating various conditions that can affect bile production, storage, and flow, which can significantly impact patient morbidity, mortality, and quality of life.