Pancreas Flashcards
Pancreas Anatomy
retroperitoneal organ
lies posterior to the stomach, duodenum, proximal jejunum of the small bowel, also the transverse colon run horizontallyh acraoss the ab
contained in the anterior pararenal space
drapes across the mid aspect of the ab, just under the xyphoid process
pancreas segments
4 primary
head
neck
body
tail
pancreas head
cradled in the C-loop of the duodenum,
IVC posterior
GDA anterolateral border
CBD posterior and lateral
Pancreas Uncinate process
located anterior to the IVC and posterior to the SMV
Pancreas vascular landmarks
aorta
IVC
SMA
SMV
splenic vein
portal vein
Main pancreatic duct
duct of Wirsung
courses entire lenght of pancreas
enters duodenum via the ampulla of vater
pancrease accessory duct
Duct of Santori
drains the anterior segment of the head
>2mm internal measurment is abnormal
Vascular structure pancreatic head
right lateral to SMV
anterior to IVC
inferior to portal vein
Vascular structure Uncinate process
posterior to SMV
may completely surround SMV
anterior to aorta
vascular structure neck
anterior to portal confluence
vascular structure body
anterior to SMV
splenic vein
SMA
vascular structure tail
splenic vein marks posterior border
Duct of Wirsung
Main pancreatic duct
primary duct extending entire length of pancreas
seen as 2 echogenic lines especially in neck/body
receives tributaries from the lobules
enters the duodenum with the common bile duct at the ampulla of vater
sphincter of Oddi-small muscle that guards the ampulla of vater
duct of santorini
secondary duct
drains the upper anterior head
endters the duodenum at the minor papilla
2cm proximal to the ampulla of vater
just draions the head
not normally seen on ultrasound
Common bile duct
CBD
runs inferior in the free edge of the lesser omentum to level of the duodenum
travels posterior to the first portion of duodenum where it forms a common trunk with the pancreatic duct and opens into the duodenum
ducts have smooth muscle surrounding them to make it easier to transport the pancreatic fluid
Pancrease body
longest segment
antrum of the stomach lies anterior
pancreas tail
most difficult to visualize
course left lateral aspect of the body, extending to the hillum of the spleen
splenic vein serves as the posterior border
left kidney is posterior to the tail
Pancrease vascular supply
supplied by the splenic artery and the pancreaticoduodenal arteries
veinous drainage is through tributaries of the splenic and SMV
Panreatic congential anomilies
Agenisis
pancreas divisum
ectopic
annular
Agenesis
missing body and tail with a large (hypertropic) head
pancreas divisum
lack of fusion of the dorsal and ventral pancreatic buds
ectopic
most common anomalie
pancreatic nodules are found throughout the GI tract
.5-2.0cm in size
acute pancreatitis and tumor may be found in these nodules
annular
head of the pancreas surrounds the second portion of the duodenum
male prevalence
pancreas functions
Exocrine
Endochrine
Exocrine
digestive function
Acini cells
produces up to 2 liters of pancreatic juice per day
arranged in sac-like structures
juice converges into the two ducts which drain the juice into the duodenum for digestion
pancreatic juice enzymes capable of completing almost all of the digestion of our food
Excocrine function
produces pancreatic juice to aid in digestion
enzymes
lipase
trypsin
amylase
nucleases
sodium bicarbonate
lipase
breaks down fats
trypsin
digest proteins
amylase
digest carbohydrates
nucleases
digest nucleic acids
sodium bicarbonate
neutralizes gastric acids
ph of juice needs to be almost neutral for best action
Exocrine enzyme triggers
chyme (partially digested food) in the duodenum triggers release of hormones that start pancreatic juice formation
gastrin
cholecystokinin
aceytlcholine
secretin (sodium bicarbonate)
these now enter duodenum after allowing the sphincter of Oddi to relax
Endocrine function
produces glucagons and insulin
insulin production
alpha, beta and delta cells within the islets of Langerhans
Insulin
regulates the metabolism of sugars
insufficient leads to diabetis mellitus
hormone that causes glycogen formation from teh glucose stored within the liver
glucagon
changes the forms of sugar
hormone that causes our cells to release glucose to meet the bodies energy needs
stimulates the liver to convert glycogen to glucose and increase sugar levels
gastrin
autoregulator
inhibits the production of both insulin and glucagon
Beta cells
most prevalent cells
produces insulin
enables cells within insulin receptors to take up clucose which lowers blood sugar
alpha cells
produce glucagon
delta cells
smallest number of cells
produce gastrin
Amylase
digestive enzyme produced by the pancreas as well as the parotid glands, bowel and gynecological system
certain types of pancreatic disease escapes into the surrounding tissue causing death of tissue, resulting in severe pain and inflammation
ANypase lab tests
blood test twice normal usually indicates acute pancretitis, or obstruction of panc duct, acute cholecystitis, perforated peptic ulcer, alcohol poisoning
differentials include mumps, ischemic bowel disease, pelvic inflammatory disease
urine amylase
may be elevated in pancreatitis
diseases not affectin the pancreas may cause an elevation of blood serum amylase with elevation
Lipase
enzyme excreted only by the pancreas
small amounts pass into the blood
used to assess damage to the pancreas
rises at teh same rate as amylase, but persists for a longer period of time
lipase differentials
obstruction of panc duct
pancreatic CA
acute cholecystitis
glucose
controls the blood sugar lever in the body
GTT performed to asses a disorder of glucose metablolism
elevated Glucose differentials
diabetes
chronic liver disease
overactivity of several of the endocrine glands
decreased glucose differential
tumor of the islets of langerhans
normal pancreatic tissue sonographically
echogenicity is caompared to liver
echo intensity is slightly less than surrounding retroperitoneum and slightly greater than liver
texture depends on amount of fat dispersed between the lobules
fat is strongly echogenic so may be isoechoic with surround retroperitoneal fat
echotexture-homogeneous
surface smooth to slightly lobular
Scanning pancreas
NPO 6-8 hrs
2.5-5Mhz adults
5-7Mhz peadiatrics
left lobe for window
deep inspiration to allow liver to displace inferior
supine, oblique and upright positions (distends vascular structures) also valsalva
Pancread normal size
head <=3 cm
Neck <=2.5 cm
Body <=2.5 cm
tail <=2 cm
pancrease normal echogenicity
>liver
<>spleen (depends on fibrous/fatty content)
