Anatomy Quiz #2- Liver+GB

lectures 4-5

Transverse view of liver

Anterior view of liver

GI and Billiary system

The liver overview

• Largest internal organ

• Occupies right hypochondriac epigastric region and part of the left hypochondrium

• Lies inferior to the diaphragm

• Lies in contact with diaphragm, esophagus, duodenum, right kidney, right adrenal, gallbladder right and the colic flexure

Glisson’s capsule

The fibrous layer covering entire liver

Reidels lobe

A tongue/finger like projection of right lobe more common in women

Appearance

• Contour and shape of liver vary according to patient’s body habitus

• Most of the liver is covered by the peritoneum except Bare area

• The margins of the bare area of the liver are formed by the coronary ligaments

  • Area that rests directly on the diaphragm

  • IVC fossae

  • Porta Hepatis

  • Gallbladder fossae

Porta Hepatis

• Hilum of liver where different structures enter/exit

• On posterior inferior surface of organ

Portal Triad

• Portal vein

• bile duct

• hepatic artery

Liver lobes LABELED

Right lobe

• Exceeds left lobe by ratio of 6:1

• Occupies right hypochondrial region

• Inferior surface marked by three fossae (porta hepatis, gallbladder, IVC)

Left lobe

• Smaller than RLL and varies considerably in size and shape

Caudate lobe

• Small lobe on posteroSUPERIOR surface of LEFT lobe

• Bounded by porta hepatitis, fossa for IVC, and ligamentum venosum.

Quadrate lobe-known as medium segment of left lobe

• Small lobe on posterior INFERIOR surface of LEFT lobe

• Lies between gallbladder and fossa by ligamentum teres

Microscopic

Under microscope, the functional cells of the liver are known as hepatocytes

Liver fissures

• Main lobar fissure

  • Separates right and left lobes

• Right intersegmental fissure

  • Divides right lobe into anterior and posterior segments

• left intersegmental fissure

  • Divides left lobe into medial and lateral segments

Cauinaud’s liver anatomy

• Claude couinad- a french surgeon and anatomist was the first to describe segmental liver anatomy

Liver ligaments

• Connected to the diaphragm and abdominal wall by falciform ligament, ligamentum teres, coronary ligament (left/right), and triangular ligament (left/right)

Falciform ligament

• Attaches anterior surface of liver to anterior abdominal wall

• Divides right/left lobes as a peritoneal fold

• Free margin of the ligament contains ligamentum teres

Ligamentum teres

• Obliterated fetal remnant of the umbilical vein in the fissure

• Divides left lobe into medial and lateral segments

Coronary ligament

Attach superior surface of the liver to the diaphragm

Triangular ligament

• Attach superior sides of surface of liver sides to diapham

Ligamentum venosum

• Fibrous remnant of ductus venosus of fetal circulation

• Sits between caudate lobe and main parts of left lobe

Hepatic Recesses

• Spaces between liver and surrounding structure

• Clinical importance due to infected fluids that can collect in three areas forming an abscess

  • Subphrenic spaces

  • Subhepatic space

  • Morrisons pouch

Subphrenic spaces (left right)

Located between diaphragm and liver on either side of the falciform ligament

Subhepatic space

Between inferior surface of liver and stomach

Morrisons pouch

• Space posterior to right liver lobe and anterior to right kidney

• Right subhepatic space

Liver blood supply

• Recieves dual blood supply from the portal vein and the hepatic arteries

• Portal vein supplies 75% of blood to liver while hepatic arties supply 25%

Transverse view of liver segments (slide 43)

Biliary system

• The biliary system is composed of the gallbloadder and bile ducts (intra/extrahepatic)

• Serves to drain the liver of bile and store it until it is transported to the duodenum to aid in digestion

• Together with the liver and pancreas the biliary system plays a role in the digestive process

Bile ducts

• The intrahepatic ductal system begins at a microscopic level in the liver lobule

• The intrahepatic ducts merge into larger ducts as they follow a course from the periphery to the central portion of the liver eventually forming the RIGHT and LEFT hepatic duct

• The ducts run beside the hepatic arteries and protal veins throughout the liver parenchyma

The RIGHT and LEFT hepatic duct into the COMMON hepatic duct

• unite at approximately the level of the porta hepatis and together they form the COMMON HEPATIC DUCT which marks the beginning of the EXTRAherpatic biliary system

• the COMMON hepatic duct is located anterior to the portal vein and lateral to the hepatic artery in its caudal descent from the porta hepatis

• the COMMON hepatic duct runs PARALLEL with the PORTAL VEIN, travels medially in the body and is joined by the CYSTIC DUCT to form the COMMON BILE DUCT

Common Bile Duct

• role is to transport bile from the gallbladder to the duodenum

• continues caudal descent along hepatic artery and portal vein

• curves slightly to the right away from the portal vein and then posterior and medium to the first part of the duodenum behind pancreas head

• distal portion lies in a groove on the posterior surface of the head of the pancreas where it joins the main PANCREATIC duct

ampulla of vater

• common bile duct and main pancreatic duct form the apmulla of vater which empties its contents through the major papilla (opening of duodenum)

• the opening of the duodenum is controlled by the SPHINCTER OF ODDI

cystic duct

• 4cm in length

• connects gallbladder to biliary tree by joining the common hepatic duct

• cystic duct+common hepatic duct= common bile duct

• contains tiny projections (spiral valves) which serve to keep lumen of the duct open

gallbladder

• reservoir for storign and concentrating bile before going to duodenum

• intraperitoneal organ

• pear shaped

• fundus/body/neck

fundus

• common for gallstones to collect

body

• lies to the right of the porta hepatis and continues as the cystic duct before meeting with the hepatic to the COMMON BILE DUCT

Gallbladder layers

• serosal (OUTER)

• fibromuscular (middle) controls contractions

  • stimulated by cholecystokinin to force bile into the duodenum in response to fat/protein ingestion

• mucosal (inner) ruage is found

bile

• alkaline fluid formed in the liver

• stored in gallbladder

• discharged into duodenum

• used to assist digestion and absorption of fat and eliminate cholesterol/bilirubin

rugae

folds of the wall in an expandable organ

gb blood supply

• cystic artery supplies from the right hepatic artery

• drainage is via cystic vein into the portal vein

major impression in the right lobe

• right kidney and COLONIC FLEXURE

what separates the right and left lobe of the liver?

middle hepatic vein (falciform cannot be seen in scan)

in coronal view what would you see first from the right to left?

you would see the gallbladder first (coronal u get a slice of tje back half of body)

the bare area of the liver is formed by the?

coronary ligaments