Clinical anatomy and embryology of the pancreas

Question 1

what are the endocrine and exocrine functions of the pancreas

Answer 1

The pancreas has two main functions: an exocrine function that helps in digestion and an endocrine function that regulates blood sugar.

Question 2

what are the 3 primary embryonic germ layers

Answer 2

ectoderm
mesoderm
endoderm

Question 3

What embryonic developmental process leads to the formation of the three primary germ layers?

Answer 3

gastrulation

Question 4

What are the structures derived from the primary embryonic endodermal germ layer?

Answer 4

The main derivative of the endodermal germ layer is the epithelial lining of the Gastrointestinal Tract including the pharynx.

It also forms:
the epithelial lining of the respiratory tract, the urinary bladder and urethra, and the tympanic cavity and auditory tube.

the parenchyma (secretory tissues cells) of the thyroid, parathyroid, liver, and pancreas

Question 5

what are the walls of the GIT smooth muscles and other connective tissues are derived from the

Answer 5

mesoderm.

Question 6

the foregut Extends from the mouth to the point where the what enters the duodenum

Answer 6

hepatopancreatic ampulla enters the duodenum

Question 7

at the 2nd part of the duodenum what becomes what

Answer 7

foregut and midgut

Question 8

where does the midgut extend from

Answer 8

Extends from the point where the hepatopancreatic ampulla enters the duodenum to the junction between the proximal 2/3 and the distal 1/3 of the transverse colon.

Question 9

where does the midgut become hindgut

Answer 9

2/3 along transverse colon

Question 10

the hindgut extends from where to where

Answer 10

Extends from the junction between the proximal 2/3 and the distal 1/3 of the transverse colon to the anus.

Question 11

exocrine enzymes

Answer 11

chymotrypsin 
amylase 
trypsin 
lipase 
nuclease

Question 12

the pancreas if formed by two buds from the endodermal lining of the duodenum what are they

Answer 12

dorsal pancreatic bud

ventral pancreatic bud ( out pocket of th bile duct) - this also has the liver bud on It

Question 13

the gut rotates and the dorsal pancreatic bud moves to the right and ventral bud moves dorsally ( duodenum flops over)
the ventral pancreatic bud fuses with the lower part of the dorsal pancreatic bud and lies post-inf. The ventral pancreatic bud forms the what of the pancreas

Answer 13

uncinate process

Question 14

the rest of the pancreas is formed by what

as well as the the main pancreatic duct

Answer 14

dorsal pancreatic bud

Question 15

proximal part of the duct may persist as what

Answer 15

accessory pancreatic duct

Question 16

due to close proximity between the ventral pancreatic bud and duct with the proximal part of the bile duct the two duct fuse to together to from what

Answer 16

hepatopancreatic ampulla ( of vater) - gallstone here causing jaundice

Question 17

pancreatic islet of langerhans and the other secretory cells develop from the endodermal parenchymatoru tissue cell in the third month of fatal life. secretion of what begins at about the 5th month of fetal life.

Answer 17

insulin

Question 18

what is an annular pancreas

Answer 18

Formed as a result of improper rotation and migration of parts of the tissues of the ventral pancreatic bud with the rotation of the duodenum.

May constrict the duodenum

Question 19

accessory pancreatic tissue can form where

Answer 19

Ectopic pancreatic tissue may develop either in the oesophagus, stomach and duodenum or in the small intestine.

Question 20

where does the head of the pancreas sit

Answer 20

in the c of duodenum and tail at the spleen

IVC portal vein and SMA and aorta are behind it

Question 21

is the pancreas retro or intra peritoneal

Answer 21

retroperitoneal

Question 22

blood supply to pancreas

Answer 22

gastrodudodenal artery of the common hepatic
Ant nd post pancreaticoduodenal

splenic artery
SMA supplies vessels to

Question 23

venous drainage of pancreas

Answer 23

splenic and sup mesenteric vein and hepatic portal vein

Question 24

pancreatic cancer metastases early due to what

Answer 24

good blood supply

Question 25

lymphatic drainage too

Answer 25

pancreaticosplenic Los and pyloric nodes and SMln and colic lNs via hepatic nerves

Question 26

nerve supply of pancreas

Answer 26

vagus and abdominopelvic splenic nerves

Question 27

pancrea5ic secretion is primarily hormonally mediate by what hormones

Answer 27

secretin and cholecystokinin of the duodenal epithelium.

Question 28

centroacinar cells do what

Answer 28

Perform exocrine functions, synthesize and secrete the digestive enzymes, which include amylase, trypsin, chymotrypsin, lipase and nucleases.

Question 29

stellate cells do what

Answer 29

Perform functions relating to tissue repair and destruction of tumour cells.

in an islet - alpha cells inner ring, beta in middle with some L shaped delta cells , f cells in wall to

Question 30

Blockage of hepatopancreatic ampulla by …….. could lead to pancreatitis due to reflux of bile into the pancreatic duct.

Answer 30

gallstone- leads to obsturicve jaundice

hepatic caused by hepatitis and trans enzymes used

Question 31

what procedure using a fibre-optic endoscope passed through the mouth, oesophagus, stomach and duodenum and an injected radiographic contrast medium for the diagnosis of both pancreatic and biliary disease.

Answer 31

ERCP

endoscopic , retrograde cholangiopancreatogrpahy

Question 32

two types of pancreatic cancer

Answer 32

exocrine cancer -95% called adenocarcinoma originates mainly in the head of the pancreas

endocrine pancreatic cancer called pancreatic neuroendocrine tumours

Question 33

what is Courvoisier’s law;

Answer 33

if gallbladder is palpable in a jaundiced patient, it is unlikely to be due to gallstones, because stones would have given rise to chronic inflammation and subsequently fibrosis of gallbladder therefore, rendering it incapable of dilatation.

gallstones make the gallbladder shrink

Question 34

Cancer of the head of the pancreas often compresses and obstructs the bile duct, enlargement of the gallbladder and/or the hepatopancreatic ampulla because of its close relationships
this leads to what

head better than neck and body

Answer 34

obstructive jaundice

Cancer of the neck and body of the pancreas may cause hepatic portal or inferior vena cava obstruction.

The extensive lymphatic drainage of the pancreas into relatively inaccessible lymph nodes, and the fact that pancreatic cancer typically metastasizes to the liver early via the hepatic portal vein, make surgical resection of the cancerous pancreas a near futile exercise.

Question 35

what procedure involves removal of most of the pancreas for treatment of pancreatic cancer and pancreatitis

Answer 35

whipples procedure - pancreaticoduodenoctomy - tumours that haven’t spread

Question 36

steps in whipples procedure

Answer 36

surgeon removes head of pancreas and lower end of stomach.
the duodenum and gall bladder and some of the bile ducts are removed.
this includes lymph nodes

the remaining stomach and bile duct are joint to the small intestine and the pancreas is joined either to the small intestine and stomach too