Ampulla of vater

General Information
Latin	ampulla hepatopancreatica
Greek
TA98
TA2
FMA
Details
System	Digestive system
Artery	Pancreaticoduodenal artery
Vein	Pancreaticoduodenal vein
Nerve	Vagus nerve
Lymphatic drainage
Precursor	Common bile duct, Pancreatic duct
Function
Identifiers
Clinical significance
Notes

The ampulla of Vater, also known as the hepatopancreatic ampulla, is an important anatomical structure in the digestive system. It is the confluence where the common bile duct and the pancreatic duct merge and empty their contents into the duodenum, which is the first section of the small intestine.

Anatomy

The ampulla of Vater is located in the second part of the duodenum, specifically at the major duodenal papilla. It is a small, flask-like structure that serves as a critical junction for the delivery of bile and pancreatic juices into the intestinal tract. The ampulla is surrounded by the sphincter of Oddi, a muscular valve that regulates the flow of digestive juices and prevents the backflow of intestinal contents.

Structure

The ampulla of Vater is formed by the union of the common bile duct and the pancreatic duct. The common bile duct carries bile from the liver and gallbladder, while the pancreatic duct carries digestive enzymes from the pancreas. The ampulla is approximately 2-3 cm in length and is located on the medial wall of the duodenum.

Sphincter of Oddi

The sphincter of Oddi is a complex of smooth muscle fibers that surrounds the ampulla of Vater. It controls the flow of bile and pancreatic juice into the duodenum and prevents the reflux of duodenal contents into the ducts. The sphincter is innervated by the vagus nerve and is influenced by hormonal signals such as cholecystokinin.

Function

The primary function of the ampulla of Vater is to facilitate the entry of bile and pancreatic enzymes into the duodenum. Bile is essential for the emulsification and absorption of dietary fats, while pancreatic enzymes are crucial for the digestion of carbohydrates, proteins, and fats. The coordinated release of these substances is vital for efficient digestion and nutrient absorption.

Bile Secretion

Bile is produced by the liver and stored in the gallbladder. Upon ingestion of a meal, especially one containing fats, the hormone cholecystokinin is released, stimulating the contraction of the gallbladder and the relaxation of the sphincter of Oddi, allowing bile to flow into the duodenum.

Pancreatic Enzyme Secretion

The pancreas secretes a variety of digestive enzymes, including amylase, lipase, and proteases. These enzymes are released into the pancreatic duct and subsequently into the ampulla of Vater, where they enter the duodenum to aid in digestion.

Clinical Significance

The ampulla of Vater is a site of clinical importance due to its role in digestive processes and its potential involvement in various diseases.

Diseases and Disorders

Ampullary Cancer

Ampullary cancer is a rare malignancy that arises from the ampulla of Vater. It can cause obstruction of the bile duct, leading to jaundice, and may also obstruct the pancreatic duct, causing pancreatitis. Diagnosis is typically made via endoscopic retrograde cholangiopancreatography (ERCP) and biopsy.

Gallstones

Gallstones can obstruct the common bile duct at the level of the ampulla, leading to a condition known as choledocholithiasis. This can result in jaundice, biliary colic, and pancreatitis.

Pancreatitis

Obstruction or dysfunction of the ampulla of Vater can lead to pancreatitis, an inflammation of the pancreas. This can occur due to gallstones, tumors, or sphincter of Oddi dysfunction.

Procedures

Endoscopic Retrograde Cholangiopancreatography (ERCP)

ERCP is a diagnostic and therapeutic procedure used to examine and treat conditions of the bile ducts and pancreatic duct. It involves the insertion of an endoscope through the mouth into the duodenum, where the ampulla of Vater can be accessed and cannulated.

Sphincterotomy

Sphincterotomy is a procedure in which the sphincter of Oddi is cut to relieve obstruction and facilitate the flow of bile and pancreatic juice. It is often performed during ERCP.

See Also

• Common bile duct
• Pancreatic duct
• Duodenum
• Sphincter of Oddi
• Pancreatitis