RAD ANA LEC MIDTERM

• Bile is manufactured in the liver
• Bile is stored in the gallbladder
• The liver is the largest solid organ in the human body
• The liver weighs 3-4 lbs (1.5-2 kg)
• The liver occupies most of the right upper quadrant
• Of the nine abdominal regions, the liver occupies almost all of the right hypochondrium, a major part of the epigastrium, and a significant part of the left hypochondrium.
• The superior border of the liver is the widest portion, approximately 8-9 inches (20-30cm)
• The right border of the liver is its greatest vertical dimension, approximately 6-7 inches (15-17.5 cm)
• In the average person, the right border extends from the diaphragm to just below the body of the tenth rib
• THe liver is protected by the lower right rib cage
• The gallbladder is typically nestled centrally in the posterior inferior region of the liver
• Only the two major lobes of the liver can be seen
• A much larger right lobe is separated from the smaller left lobe by the falciform ligament
• The two minor lobes of the liver (caudate and quadrate) can be found on the posterior aspect of the right lobe
• The quadrate lobe is located on the inferior surface of the right lobe between the gallbladder and the falciform ligament.
• The caudate lobe extends superiorly to the diaphragmatic surface and the large inferior vena cava contours over the surface of this lobe.
• The liver performs more than 100 different functions, but the function most applicable to radiographic study is the production of large amounts of bile
• The liver secretes 800 to 1000 mL or about 1 quart of bile per day
• The major functions of bile are to aid in the digestion of fats by emulsifying fat globules and the absorption of fat following its digestion.
• Bile is formed in small lobules of the liver and travels by small ducts to the right or left hepatic ducts.
• The right and left hepatic ducts join to continue as the common hepatic duct
• Bile is carried to the gallbladder via the cystic duct for temporary storage, or it may be secreted directly into the duodenum via the common bile duct
• The common bile duct is joined by the pancreatic duct at the hepatopancreatic sphincter, which empties into the duodenum via the duodenal papilla
• THe gallbladder is a pear-shaped sac composed of three parts: fundus, body and neck
• The cystic duct is 3-4 cm long
• The folds of the cystic duct are called the spiral valve, which functions to prevent distention or collapse of the cystic duct
• The normal gallbladder is 7-10 cm long and approximately 3 cm wide
• THe normal gallbladder generally holds 30-40 mL of bile
• The three primary functions of the gallbladder are:

  1. Store bile
  2. Concentrate bile
  3. Contract when stimulated
• Bile is concentrated within the gallbladder as a result of hydrolysis
• In abnormal situation, when too much water is absorbed or the cholesterol becomes too concentrated, gallstones may form in the gallbladder.
• The gallbladder normally contracts when foods, such as fats or fatty acids, are in the duodenum. These foods stimulate the duodenal mucosa to secrete the hormone cholecystokinin (CCK).
• The common bile duct averages approximately 7.5 cm in length and has an internal diameter about the size of a drinking straw.
• The terminal end of the common bile duct is closely associated with the terminal end of the pancreatic duct
• The pancreatic duct is also known as the duct of Wirsung
• In about 40%, the common bile and pancreatic ducts pass into the duodenum as two separate ducts with separate openings.
• In about 60%, the common bile duct joins the pancreatic duct to form the hepatopancreatic ampulla.
• In 60% of the individuals, the hepatopancreatic ampulla becomes narrower as it passes into the duodenum and is a common site for impaction of gallstones
• Near the terminal end of the hepatopancreatic ampulla, the duct walls contain circular muscle fiber termed the hepatopancreatic sphincter
• The hepatopancreatic ampulla is also termed ampulla of Vater