Anatomy of the biliary tract and spleen

Question 1

Gut associated organs

Answer 1

Liver

Spleen

Gall bladder

Pancreas

Question 2

Bile

Answer 2

Secreted by hepatocytes into bile canaliculi

Question 3

Biliary course

Answer 3

Depicts travel of bile from intrahepatic ducts to entering duodenum

Question 4

Biliary tree

Answer 4

Sectoral ducts of right/ left liver

Right/ left hepatic duct

Common hepatic duct (cystic duct)

Common bile duct (pancreatic duct)

Duodenum

Question 5

Intrahepatic bile duct

Answer 5

Runs parallel to portal vein and hepatic artery

Smaller bile ducts (ductules)- much thinner wall and cuboidal epithelium

Larger bile ducts have a loose connective tissue (flexible) and single layer of columnar epithelium

Question 6

Extrahepatic bile duct

Answer 6

7cms

Runs in free edge lesser omentum

Joined by cytic duct near porta hepatis

Meets with right end of pancreatic duct0 ampulla vater

Enters 2nd part of duodenum at sphincter of oddi

Question 7

Structure of exxtrahepatic bile duct

Answer 7

Duct wall- dense fibrous connective tissue

Wall also contains smooth muscle cells

Lumen- highly columnar epithelium

Blood: cystic vessels (from coeliac and into portal)

Question 8

Gall bladder anatomy

Answer 8

Lodged in a fossa on the visceral surface, right lobe of liver

Between inferior border of liver (ant) and duodenum (post)

Conical, pear shaped

About 10cm in length and 3 in diameter

Held by peritoneum (forms outer wall)

Divided into fundus (lower aspect), body and neck

Wall: simple columnar epithelium, smooth muscle

Question 9

Functions of gall bladder

Answer 9

Concentrate and store bile

Selectively absorb bile salts

Excrete cholesterol

Excrete mucous

Question 10

Mechanisms

Answer 10

1. Contraction/ emptying of stomach
2. Fatty foods in duodenum
3. Cholecystokinin release
4. Sphincter of odd relaxed
5. Emulsification of fat

Question 11

Gall stones

Answer 11

Physical changes in bile e.g. low bile salts, excessive cholesterol

Stones can partially or fully obstruct flow of bile

Question 12

Biliary colic

Answer 12

Gall stone blocks duct

Crampy right upper abdominal pain that comes and goes repeatedly

Question 13

Acute cholecystitis

Answer 13

Inflammation gall bladder that also causes pain on right upper quadrant

Question 14

Visceral pain

Answer 14

Most pain signals from organs within abdomen is carried alongside sympathetic fibres

Question 15

Pancreas anatomy

Answer 15

Oblong in shape (comma shaped)

12-15cm long

3cm in width

Divided in (broad) head, (tapering) body and (sharp) tail

Exocrine secretions are collected into small ducts

Small ducts unit to form the pancreatic duct

Ducts of Wirsung joins common bile duct to become the hepatopancreatic ampulla

Ampulla of vater enters duodenum about 10cm post-pyloric sphincter

Secondary duct (of santori) enters duodenum about 2cm superior to major duodenal papilla

Question 16

Pancreas location

Answer 16

Head at the level of the descending duodenum

Body behind stomach and extends towards spleen

Just below L1

Epigastric region

Question 17

Pancreas arteries

Answer 17

Pancreatic, branches from the coeliac

Join forming an arc (gastroduodenal and pancreaticoduodenal)

Question 18

Pancreas veins

Answer 18

Portal

originally from splenic and superior mesenteric

Question 19

Pancreas nerves

Answer 19

Coeliac ganglia and vagus

Question 20

Pancreas histology/ function

Answer 20

Both an exocrine and endocrine gland

Exocrine portion: clusters aka acini cells- pyramidal epithelium (98-99%)

Exocrine: secretion of digestive enzymes, the pancreatic juice

Endocrine portion: centreacinar cells aka islets of langerhans- cuboidal epithelium (1-2%)

Endocrine: secretion of hormones, e.g. insulin

Question 21

Inflammation (pancreatitis)

Answer 21

Gallstones

Heavy alcohol intake

Cystic fibrosis

High levels of calcium of blood fats

Question 22

Pancreatic cancer

Answer 22

Obstructive jaundice (gallstones)

Heavy alcohol intake

Smoking

Genetics

Question 23

Spleen

Answer 23

Part of lymphatic system

Largest single mass of lymphoid tissue

Regarded as a blood gland

Underlies 9/10/11th rib on LHS

At the let hypochondriac region of the abdomen

Oval in shape

Question 24

Spleen anatomy

Answer 24

12cm in length but can vary- age, disease

Outer surface shows indentations, caused by neighbouring organs (stomach, left kidney, left flexure of colon)

Parenchyma (inner part of spleen): contain the lymphatic tissue and blood vessels

Nerve supply: branches of coeliac nerve plexus

Question 25

Spleen function

Answer 25

Parenchyma: two pulps- red and white

Red pulp: blood filled venous sinuses

White pulp: lymphatic tissue (lymphocytes, macrophages)

Functions:

• immune (like in lymph nodes)
• removal by macrophages of old blood cells
• storage of platelets
• production of blood cells (foetal life)