Liver Flashcards
The posterior edge of the liver straddles what major vessel?
IVC
What lies posterior to the liver, major vessel?
IVC
The peritoneal duplications of the liver are referred to as ligaments, the diaphragmatic peritoneal duplication are referred to as what?
coronary ligaments (whose lateral margins on right and left side are the triangular ligaments)
This is a thin membrane of anterior liver surface, connecting to the diaphragm, abdominal wall and umbilicus;
falciform ligament
This runs along the inferior edge of the falciform ligament from the umbilicus to the umbilical fissure;
ligamentum teres
What’s the ligamentum teres?
obliterated umbilical vein
What structure used to be the obliterated umbilical vein?
ligamentum teres (runs along the inferior edge of falciform ligament)
On posterior surface of left liver we have the ligamentum venosum, what’s that?
obliterated sinus venosus
How does venous drainage of the liver occur?
thru R, L, and M hepatic veins–> empty into suprahepatic IVC
The liver is covered in peritoneum except in these specific areas:
gallbladder fossa
porta hepatis
on either side of IVC on posterior aspect of liver
What is the area on the posterior liver to the right of IVC called?
bare area of the liver
In the adult liver what does the obliterated umbilical vein and ductus venosus become?
left umbilical vein—> ligamentum teres, runs in the falciform ligament
ductus venosus–> ligmentem venosum
Fetal liver plays an important role in what?
hematopoiesis
What divides the liver into right and left lobes?
Cantlie’s line (portal fissure)
Where does Cantlie’s line run thru which divides the liver into right and left lobes;
runs from the GB to left side of IVC
What segment of liver seen posteriorly embracing IVC?
segment 1 (caudate lobe)
Caudate lobe is also known as which liver segment?
1
What are the segments of the right side of the liver?
5, 6, 7, 8
What are the segments of the left side of the liver?
left medial segments; IV A, IV B
left lateral segments; II, III
What secures the liver to the diaphragm?
right and left triangular ligaments
What ligaments of liver can we dissect in an avascular plane to mobilize it for resection?
falciform, triangular, coronary ligaments, round ligaments
The hapatoduodenal ligament is AKA?
porta hepatis
What does the porta hepatis contain?
portial triad; CBD, hepatic artery, portal vein
What’s the Pringle maneuver?
clamping of the hepatoduodenal ligament which contains the CBD, portal vein and hepatic artery
What do we find deep to the porta hepatis?
foramen of winslow–> entrance into the lesser sac
this will allow complete vascular inflow of liver by clamping the porta hepatis
THe liver is separated into right and left lobes by plane from GB fossa to IVC known as;
Cantlie’s line
This liver lobes lies to the left and anterior to the IVC:
segment 1; caudate lobe
What segments make up left side of liver:
left lateral segments: II, III
left medial segments: IVa, IVb
What segments make up left side of liver?
left lateral segments: II, III
left medial segments: IVa (cephalad), IVb
What are the segments of the right lobe of liver?
R-anterior lobe; V, VIII
R-posterior lobe; VI, VII
The liver has a dual blood supply consisting of what?
hepatic artery
portal vein
What % of blood delivered to liver by hepatic artery and portal vein?
portal vein delivers 75%
hepatic artery delivers 25%
Where does hepatic artery originate from?
celiac trunk–> splenic, left gastric, common hepatic
common hepatic–> gastroduodenal, hepatic artery proper
hepatic artery proper–> R + L hepatic arteries
In 76% of cases, the hepatic artery proper divides into right and left hepatic arteries, what are some anatomic variations we commonly see?
Replaced right hepatic artery from SMA (10-15%)
Replaced left hepatic artery from Left Gastric A (3-10%)
replaced r and l hepatic arteries (1-2%)
completely replaced common hepatic artery off of SMA (1-2%)
The cystic artery feeding the GB usually arises from what artery?
right hepatic artery
What forms the portal vein?
splenic vein + SMV
IMV joins into the splenic vein
What is normal portal vein pressure?
in a pt with normal physiology its 3-5 mmHg
in a pt with portal htn, portal vein pressure can be 20-30 mmHg because portal vein is valveless
What are the main hepatic veins and what do they do?
R, M, L hepatic veins
drain blood to the suprahepatic IVC and right atrium
These two hepatic veins usually form a trunk before entering into the IVC together:
left and middle hepatic veins (95% of time)
What are the connections between the portal and systemic venous system?
submucosal veins of proximal stomach and esophagus (via short gastric and left gastric veins)
umbilical and abdominal wall veins, recanalize via flow thru the umbilical vein in ligamentem teres and produce caput medusae
superior hemorrhoidal plexus receives portal flow from IMV and can form hemorrhoids
Describe the formation and course of the portal vein?
SMV joins the splenic vein posterior to neck of pancreas
the IMV joins the splenic vein (most commonly)
Where does the portal vein lie in relation to CBD and hepatic artery?
it’s more posterior to both structures
How much O2 is delivered to liver via portal vein and hepatic artery ?
50/50
Where does the hepatic artery lie in the porta hepatis?
anterior to portal vein
left of the CBD
Calot’s triangle?
cystic duct
common hepatic duct
liver edge
Difference between an accessory vs replaced vessel?
accessory; aberrant origin of a branch that is in addition to the normal branching pattern
replaced; aberrant origin of a branch that substitutes for the lack of a normal branch
Common locations of accessory cystic arteries?
can originate from proper hepatic artery
gastroduodenal artery
(can run anterior to bile duct)
Within the hepatoduodenal ligament where we have the portal triad, where does the CBD lie?
anteriorly and to the right
Anatomy of the CBD:
gives off the cystic duct to the GB
becomes the common hepatic duct
splits into right and left hepatic ducts
In what segments of the liver do we find the gallbladder residing?
IV B of left lobe
V of right lobe
The intra-pancreatic distal CBD joins with this pancreatic duct to empty into the second portion of the duodenum in the major papilla;
main pancreatic duct of Wrisung
What regulates bile flow and prevents reflux of duodenal contents into the biliary tree?
sphincter of oddi
This is a biliary reservoir that lies in segments IVB and IV of liver:
GB
What’s a normal CBD diamter?
6 mm
The GB is covered by a peritoneal layer except where?
in area adhered to the liver
Parts of the gallbladder?
body
fundus
infundibulum
neck
This part of GB AKA Hartmann’s pouch;
infundibulum (proximal to GB neck)
This is the part of the GB between the infundibulum (Hartmann’s pouch) and cystic duct:
GB neck
The first part of the cystic duct is tortuous and has mucosal duplications referred to as:
folds of Heister (regulate filling and emptying of the GB)
CBD blood supply found where?
at 3 and 9 oclock positions
Innervation of the liver?
PSNS–> left vagus–> anterior hepatic branch
right bagus–> posterior hepatic branch
SNS–> greater thoracic splanchnic nerves, celiac ganglia
Bilirubin is the breakdown product of?
normal heme catabolism
Describe bilirubin metabolism:
heme catabolism–> produces bilirubin
carried by albumin to the liver
in the liver conjugated by glucuronyl transferase to make it water soluble
majority of conjugated bilirubin excreted as waste in the intestine (intestinal mucosa is impermeable to conjugated bilirubin)
What is bile made of?
bile salts
bile pigments
cholesterol
phospholipids
How much bile i secreted daily?
approx 1.5 L (80% secreted by hepatocytes into canaliculi)
What is enterohepatic circulation?
way to reabsorb bile acids