Biliary System Flashcards
Biliary tree begins at the level of
The bile canaliculi
Intercommunicating network
Hepatocytes, where bile canaliculi are located between
Microscopic canaliculi anastomose to form
Lobular bile ducts
Travel with a
Hepatic artery and portal vein
What’s formed by the union of multiple lobular bile ducts
Right and left hepatic ducts
What forms the common hepatic duct
Right and left hepatic ducts
What is the level that the common hepatic duct is formed
Portal hepatis
Common hepatic duct
CHD Anterior to portal vein Antrolateral to right hepatic artery Travels in free edge of lesser omentum ~4mm in diameter
What forms the common bile duct
CHD and the cystic duct
How is the length of the CBD determined
By the insertion point
Where is the cystic ducts from
The gullbladder
CBD
Antrolateral to MPV
Diameter ranges up to 4mm
Travel through heaptoduodenal ligament
Hepatoduodenal ligament is part of what
Lesser omentum
What is referred to as the Mickey Mouse appearance at the porta hepatis
A cross section of the CBD, HA and MPV
HA lies what to the PV
Anterior and to the left
CBD lies what to the PV
Anterior and to the right
What are the 4 segments of the CBD
Supraduodenal
Retroduodenal
Infraduodenal
Intraduodenal
Segments of the CBD are named in relation to its position compared to what organ
Duodenum
What CBD segment enters the 2nd part of the duodenum and where does it insert
Intraduodenal and it inserts into ampulla of Vater
What does the splinter of Oddi do
Regulates bile flow
What is the narrowest part of the extrahepatic biliary tract
Intraduodenal segment
What joins the CHD about 1-2 cm above the duodenum to form CBD
Cystic duct
Aries from superior aspect of the neck of the gullbladder
Cystic duct
Cystic duct
S-shaped
~3mm in diameter and 4cm in length
Contains the spiral valves of heister
Spiral valves of heister
Tortuous area of the cystic duct
Not true valves
Prevents duct from over extending or collapsing
Does not control bile flow
If the spiral valves of heister are not true valves what are they
Mucosal folds
Landmarks for identifying the gullbladder
Main lobar fissure
RPV
duodenum
Right kidney
Size and shape of gullbladder
Varies widely from patient to patient
Usually pear or teardrop shaped
Generally 8-9cm in length and 3-5 cm in diameter
What are the three parts of the gullbladder
Fundus
Body
neck
What is the most dependent portion of the gullbladder and in what body position
Fundus in LLD
Widest portion of gullbladder
Fundus
What part of the gullbladder projects below inferior liver margin
Fundus
What is another name for gullbladder body
Corpus
What is portion of the gullbladder is the body
Middle
What surface of the liver is the body of the gullbladder in contact with
Visceral
Tapered portion of the gullbladder with spiral folds is the
Neck
Most dependant portion of the gullbladder in supine
Neck
Where is the neck of the gullbladder in a fixed portion
Main lobar fissure
The gullbladder should measure what in a fasting state
Less than 3mm
How many layers does the gullbladder wall have and what are the names
4 layers: Mucosa Muscular layer Subserous layer Serous
What is the mucosa layer of the gullbladder wall
Inner epithelial lining
Concentrates bile
What is the muscular layer of the gullbladder wall
Muscle
What is the subserous layer of the gullbladder wall
Connective tissue
What is the serous layer of the gullbladder wall
Outer layer
What is the serous layer of the gullbladder wall in contact with
Peritoneum
What is the Rokitansky-Aschoff sinuses
Abbreviated to RA sinuses
Multiple folds along the inner boarder of the gullbladder, coated with epithelial cells
Are the RA sinuses normally visualized on ultrasound
No, unless there is pathology
What is bile
Yellowish green liquid produced and secreted by hepatocytes
What does bile consist of
Water Cholesterol Pigments Inorganic salts Salts of bile acids
What does bile do
Breaks down fat
Helps absorb fatty acid, cholesterol and other lipids from the intestinal tract
How much bile salt is formed by the liver each day
1 gram
What is a precursor for bile salt
Cholesterol
What is the end product of hemoglobin decomposition
Bilirubin
What is bilirubin
Bile pigment
Where does bilirubin conjugate
In the liver
Another term for jaundice is
Icterus
What is jaundice
Yellowish tint in the body tissue due to large quantities of bilirubin
What causes jaundice
Hemolytic anemia
Acute and chronic hepatic disease
Obstructive jaundice
Inability of bilirubin to conjugate
What is the arterial blood supply for the gullbladder
Cystic artery
Venous drainage occurs via what in the gallbladder
Cystic vein
Where does the cystic vein drain directly into
Portal vein
What is the function of the biliary ducts
Drain the liver of bile and carry it to the GI system
The function of the gallbladder
A reservoir for bile
When is bile stored till
Until it’s required to aid in digestion
How much bile does the GB hold
40-70ml
What does the full bladder do to bile and how does it do it
Concentrates bile by decreasing mucus and absorbing water
How is bile secretion controlled
By hormones
with the ingestion of fats and amino acids what does the duodenum release via the bloodstream
cholecystokinin (CCK)
what does CCK stimulate
the gallbladder to contract
the sphincter of Oddi to relax
what does the sphincter of Oddi do
regulates the passage of bile into the duodenum and prevents the reflux f GI fluids into the biliary system
where is the sphincter of Oddi located
duodenum
how long does it take the gallbladder to contract after a meal
30 mins
what happens when the small intestine is empty
sphincter closes and bile does back into the gallbladder
what happens to the sphincter of Oddi when the GB is removed
loses its tone
does the pressure in the CBD raise or lower when the GB is removed
lowers
why does the pressure change in the CBD when the gullbladder is removed
it changes to lower the intra-abdominal pressure
where does bile flow when there is no GB
into the duodenum
when does the flowing of bile occur in the duodenum when there is no GB
in fasting and non-fasting states
does some bile also remain in the ducts when there is no GB
yes
after what time period will the sphincter regain its tone
~6months
what will also appear diated on patients when the GB is removed
CBD
how dilated can the CBD get when there is no GB prestnt
up to 10mm
what is a junctional fold
a fold that occurs at the juntion of the body and neck of the GB
what does a juntional fold look similar too
a septation
what is another name for the GB neck
infundibulum
what is Hartman’s pouch
an outpouching in the area of the GB neck
what is a Pharygian cap
when the GB is partically folded onto itself in the region of the fundus
what are GB septation varients
thin walls
partical or complete dividing of the GB lumen
are GB septations common or rare
rare
other GB varients are
excessively mobile
ectopic
low lying in RLQ
totally or partically embedded in liver
sonographic apperance of the GB
anechoic or nearly anechoic structure
well defined, thin, echogenic walls
saggital: pear shaped
transverse: anechoic circle
why does a patient have to be NPO for at least 6-8 hours before an exam
because the GB contacts
what postions may be used to rule out stones lodged in the neck and cystic duct
supine
decubitus
erect
prone
to examine for fluid in and the GB what do you look at
size shape content wall thickness area around GB
how do you optimize the GB image
harmonics
what is important to minimize reverberation artifact
windows
what structure measurements usually involve placing the patient in an LPO or decubitus postion
CHD
CBD
how do you meausre the cystic duct
region of the porta hepatis
inner wall to inner wall
where do you not measure the cystic duct
at the point where it crosses the hepatic artery
indirect increased bilirubin values indicated what
hemolysis
RBC degradation
abnormal hepatocellular uptake
direct increased bilirubin values indicated what
extrahepatic obstruction
bile duct disease
intrahepatic disruption
alkaline phosphatase lab test are ordered to asses if there is an increase in what values
extrahepatic biliary obstruction
Leukocyte lab test asses and indicate what
assesses reaction of the body to infection
indicates increased values in acute and chroinic cholecystitis , which can indicate an injury ti bile ducts
HIDA scan
nuclear medicine test
evaluates function of GB
radio pharmaceutical is injected into patient which then passes through the bloof to the liver and then to the biliary system
ERCP
endoscopic retrograde cholangiopancreatography
ampulla of vater is cannulized through a tube inserted into the patient’s upper GI tract
contrast material is injected and the bile and pancreatic ducts are delineated
