The biliary system
when can you see the gallbladder best?
on an empty stomach
sections of the gallbladder
fundus, body, neck
gallbladder fossa
Indentation located on the posteroinferior portion of the right lobe of the liver where the gallbladder is situated.
phrygian cap
gallbladder variant in which part of the fundus is bent back on itself
main lobar fissure
boundary between the right and left lobes of the liver; seen as a hyperechoic line on the sagittal image extending from the portal vein to the neck of the gallbladder
what is the landmark for the gallbladder/gallbladder fossa?
main lobar fissure
what forms the common bile duct?
common hepatic duct and cystic duct
What forms the common hepatic duct?
right and left hepatic ducts
Spiral Valves of Heister
A series of mucosal folds within the lumen of the cystic duct. These move the bile in either direction where it needs to go.
CBD Measurement
1-7mm
Cystic Duct Measurement
less than 4mm
ampulla of Vater
small opening in the duodenum in which the pancreatic and common bile duct enter to release secretions
where does the common bile duct meet the pancreatic duct?
the Ampulla of Vater
sphincter of Oddi
The valvecontrolling release of bile and pancreatic juice into the bloodstream. A muscle sheath.
Cholecystokinin (CCK)
A hormone secreted by the samll intestine (duodenum) in response to the presence of fats. It promotes release of bile from the gallbladder and pancreatic juice from the pancreas,and reduces stomach motility.
choledochal cyst
the cystic dilatation of the common bile duct. NORMAL variant.
composition of bile
92% water
Other is bile salts
where is the CBD?
anterior to the portal vein. exiting at the porta hepatis.
Hartman's pouch
Small part of the GB that lies near the cystic duct where stones may collect
Mickey Mouse Sign
portal triad
how to tell the difference between a gallstone and a polyp?
gallstones have posterior shadowing and they move around
indications for biliary system sonograms
- RUQ pain
- Murphy's sign
- Nausea
- Vomiting
- Pain radiating to the right shoulder
- Jaundice or abnormal liver function tests
- Loss of appetite
- Intolerance to fatty foods/dairy
LFT
liver function test
Murphy's Sign
pain with palpation of the RUQ during inspiration, indicative of cholecystitis
Where is the pancreas?
The "C" loop of the duodenum
Retroperitoneal
sections of the pancreas
uncinate process, head, neck, body, tail
The head of the pancreas lies _________ to the IVC.
anterior
where is the CBD in reference to the pancreas?
posterolateral portion of the pancreas head
where is the GDA in reference to the pancreas head?
anterolateral to the head of the pancreas
where is the neck of the pancreas?
anterior to the SMV and confluence
where is the body of the pancreas?
anterior to the aorta, SMA, and SV
where is the tail of the pancreas?
extends to the hilum of the spleen. between stomach anteriorly and left kidney posteriorly. SV runs behind.
uncinate process
the posteromedial extension of the pancreatic head. posterior to the SMV and anterior to the IVC.
physiology of the pancreas
endocrine (hormones) and exocrine (digestive function) gland
what amount of the pancreatic function is exocrine?
90% of function is exocrine (10% endocrine)
pancreatic juice
amylase, lipase, trypsin, chymotrypsin, carboxypeptidase, nucleases, sodium bicarbonate
function of amylase
enzyme that helps digest carbohydrates
lipase function
breaks down fats
nucleases function
breaks down nucleic acids into nucleotides
sodium bicarbonate function
neutralizes pH of chyme
function of trypsin, chymotrypsin, carboxypeptidase
digest protein
acini cells
perform exocrine functions secreting digestive enzymes
beta cells
secrete insulin (glucose > glycogen)
bring sugar down
alpha cells
secrete glucagon (glycogen > glucose)
bring sugar up
delta cells
secrete somatostatin (alpha/beta inhibitor)
duct of wirsung
main pancreatic duct
Duct of Santorini
Small accessory duct of the pancreas found in the head of the gland
normal sonographic appearance of pancreas
- homogeneous
- hyperechoic compare to liver
- smooth wall margins
- variable contour
annular pancreas
Developmental malformation in which the pancreas forms a ring around the duodenum; risk of duodenal obstruction
Ectopic pancreatic tissue
pancreatic tissue without vascular or structural connection
partial duplication of tail
rare variation of pancreas. tail appears enlarged.
sonographic applications for pancreatic evaluation
- biliary obstruction
- pancreatitis
- evaluation of pancreatic pseudocysts
- endoscopic evaluation to look at lesions