Liverspleen Flashcards
What is meant by the bare area of the liver
Superior surface of liver has direct contact with the inferior surface of the diaphragm
No intervening peritoneum
Visceral peritoneum reflects at bare area.
Describe the boundaries of the bare area of the liver
Anterior boundary- reflection of the peritoneum- anterior coronary ligament
Posterior boundary- reflection of peritoneum- posterior coronary ligament
Where the two coronary ligaments come together laterally they form the right and left triangular ligaments
Describe the Mesenteries in Relation to the Stomach, Liver, and Spleen
Liver is attached to stomach and duodenum via folds of peritoneum (lesser omentum- hepatogastric and hepatoduodenal ligaments respectively)
Stomach is attached to spleen via gastrosplenic ligament
Spleen attached to left kidney via splenorenal ligament
They are folds in peritoneum
Describe the liver mesenteries and bare areas
Liver develops in the ventral foregut mesentery
Connected to anterior abdominal wall by Falciform Ligament- derived from ventral mesentery in the embryo
Connected to stomach by Lesser Omentum
Direct contact with part of Diaphragm (Bare Area of Liver)
Describe the location of the liver
Largest visceral organ in the body- primarily in the right hypochondrium and epigastric region, extending into the left hypochondrium (RUQ and LUQ)
Describe the surface anatomy of the liver
Deep to: ribs 7 -11
Mostly under the cover of ribs
Epigastrium- covered by rectus abdominis muscle- can’t palpate here
palpate under ribs
Describe the two surfaces of the Liver
Diaphragmatic- anterior, superior and posterior directions
visceral- inferiorly
Describe the recesses of the diaphragmatic surfaces of the liver
Diaphragmatic surface is smooth and domed
Subphrenic recess- separates diaphragmatic surface of the liver from the diaphragm- and is divided into right and left areas by the falciform ligament- a structure derived from the ventral mesentery
hepatorenal recess- part of the peritoneal cavity on the right side between the liver and right kidney and right suprarenal gland
Both recesses are continuously anteriorly
Describe the anatomical lobes of the liver
The liver is divided into right and left lobes by fossae for the gallbladder and IVC. The right lobe is the largest
The quadrate and caudate lobe arise from the right lobe and are functionally distinct.
Describe the ligaments of the Liver
Visceral peritoneum reflects off the liver in the form of the falciform ligament and the coronary ligaments which reflect off the right and left lobes of the liver
Superior surface of left lobe- left triangular ligament
Superior surface of right lobe- coronary ligament
All these ligaments attach the liver to the diaphragm (anterior abdominal wall)
What is attached to the falciform ligament
Ligamentum teres (round ligament of liver)- remnant of the obliterated left umbilical vein This joins the ligamentum venosum- now a fissure on the visceral surface (fissure of ligamentum venosum)
Essentially, what forms the lobes
The peritoneal reflections divide the liver externally into two main lobes and 2 accessory lobes
Summarise the visceral surface of the liver
Covered in visceral peritoneum except in the fossa for the gallbladder and at the porta hepatis
Porta hepatis serves as a point of entry into the liver for the hepatic arteries, and portal veins, and an exit point for the hepatic ducts
Describe the right anatomical lobe of the liver and its posterior relations
Inferior to posterior coronary ligament- renal impression
Inferior to this colic impression
Medial to colic impression- gall bladder
medial to this- quadrate lobe
Gall bladder moves superiorly (fundus, body, neck) into porta hepatis
IVC superiorly
Caudate lobe just medial to falciform ligament in the middle
See diagram!
Describe the left anatomical lobe of the liver and its relations
Gastric impression just inferior to the left triangular ligament
Esophageal impression medial to this
Describe the quadrate lobe
Visible on the anterior part of the visceral surface- bounded on the left by the fissure of ligamentum teres and on the right the fossa of the gall bladder
Functionally- it is related to the left lobe but anatomically to the right
Describe the caudate lobe
Visible on the posterior part of the liver
bounded on the left by the fissure of ligamentum venosum and on the right by the groove for the IVC
Functionally distinct from the right and left lobes
Describe the functional lobes of the liver
Divided into right and left functional lobes by fossae for the IVC and gallbladder
Describe the arterial supply to the liver
Right hepatic artery from hepatic artery proper ( a branch of the common hepatic artery from the celiac trunk)
The left hepatic artery from hepatic artery proper ( a branch from common hepatic artery from the celiac trunk)
Describe blood supply to the quadrate and caudate lobes
caudate- both
quadrate- left hepatic
Outline the key points regarding the visceral surface of the liver
Gall bladder and inferior vena cava mark the separation into functional R and L lobes
Grooves for foetal veins mark out minor parts of functional L lobe (quadrate and caudate Lobes)
Porta of the liver separates quadrate and caudate lobes.
Porta carries the 1) Hepatic Artery 2) Portal Vein 3) Common bile duct, and lymphatics
Summarise the visceral relations of the liver
Covered by costal margin except in upper epigastrium
Convex diaphragmatic surface
Complex visceral surface in contact with stomach, duodenum, right kidney and colon
bDescribe the key branches of the common hepatic artery
Runs to the right and divides into its two terminal branches- the hepatic artery proper and the gastroduodenal artery
the hepatic artery proper ascends towards the liver in the free edge of the lesser omentum- runs to the left of the bile duct and anterior to the portal vein, and divides into the right and left hepatic arteries near the porta hepatis
as the right hepatic nears the liver it gives off the cystic artery to the gallbladder
Describe the branches of the gastroduodenal artery
May give off supraduodenal artery and does give off posterior superior pancreaticoduodenal artery near the upper part of the superior duodenum
after these branches the gastroduodenal artery continues descending posterior to the superior part of the duodenum
reaches the lower body and divides into its terminal branches- right gastro-omental branch and anterior superior pancreaticoduodenal artery
What do the posterior and anterior superior pancreaticoduodenal arteries anastomose with
Superior pancreaticoduodenal arteries – anastomose with inferior pancreaticoduodenal arteries from the superior mesenteric artery
Describe venous drainage from the liver
IVC: drains blood from liver via three hepatic veins
Summarise blood supply of the liver
Hepatic artery, derived from the coeliac axis, supplies arterial blood to the liver
Portal vein drains, venous blood from the GI tract and spleen, into the liver
Venous blood from the liver drains directly into the inferior vena cava via 3 short hepatic veins
List some important sites for porto-systemic anastomoses
Site A
Oesophageal v - Sys
Lt gastric v - port
Site B
Inferior rectal v - Sys
Superior rectal v – port
Site C
Epigastric v - Sys
Paraumbilical v – port
Site D
Retroperitoneal v - Sys
Visceral v – port
Describe the general important areas for portacaval anastomoses
esophagus
para-umbilical region
where liver is in contact with diaphragm
where wall of G.I tract is in direct contact with posterior abdominal wall (retroperitoneal structures)
Describe the importance of these anatamoses
blockage of hepatic portal vein or vascular channels in the liver can affect patterns of venous return from abdominal parts of the G.I system
vessels that interconnect the portal and caval systems can become greatly enlarged and tortuous and rupture
the anastomoses allow blood in the tributaries of the portal system to bypass the liver, enter the caval system and thereby return to the heart.
likewise if IVC is partially compressed or obstructed
Describe the consequences of portal hypertension
can result in esophageal and rectal varicies and in caput medusae in which systemic vessels that radiate from the para-umbilical veins enlarge and become visible on the abdominal wall
Summarise the portal systemic anastomoses
May become dilated if portal blood flow through the liver is obstructed in liver disease.
Important sites of PSA are lower oesophagus, rectum, and para-umbilical veins
Haemorrhage is common from the first two sites
Summarise the biliary tree
left and right hepatic ducts form the common hepatic duct, and the cystic duct from the gall bladder then joins the common hepatic duct to form the common bile duct, passing behind the 1st part of the duodenum and head of pancreas, entering the duodenum at the major papilla
Describe the structure of the gall bladder
pear-shaped sac on visceral surface of right lobe of liver
consist of:
a rounded end (fundus)- projects from inferior border
a major part in the fossa (body)- which may be against the transverse colon and the superior part of the duodenum
narrow part (neck)- with mucosal folds forming spiral fold
Describe the relations of the gall bladder
inferior to the liver, anterior to the duodenum and superior to the transverse colon
What are the consequences of neoplasms in the head of the pancreas
Neoplasms of head of pancreas can obstruct the ducts here
jaundice- excess bile in the blood
How can large gall stones enter the duodenum
large gall stones may enter duodenum directly if a cholecystoenteric fistula forms
Where can small gallstones pass
Into the bile duct- and are trapped in the region of the sphincter of the ampulla- obstructing the flow of bile into the duodenum
this in turn, produces jaundice
Describe the basic characteristics of the spleen
Develops as part of the vascular system in the part of the dorsal mesentery that suspends the developing stomach from the body wall
In the adult, the spleen lies against the diaphragm in the area of rib 9- 10
In the LUQ and left hypochondrium
Summarise the spleen
Largest lymphoid organ in the body
Fist -sized, suspended in dorsal foregut mesentery (gastro-splenic and spleno-renal ligaments)
Lies posteriorly on L side under ribs 9-11
Relations with stomach, L kidney, L (splenic) flexure of colon, tail of pancreas
Traumatic rupture causes severe haemorrhage
Describe the connections of the spleen
greater curvature of the stomach- gastrosplenic ligament (contains the short gastro and gastro-omental vessels)
left kindey- splenorenal ligament (contains splenic vessels)
both these ligaments are part of the greater omentum
Describe the splenic hilum
entry point for splenic vessels, and occasionally the tail of the pancreas reaches this area
on medial surface
not covered in visceral peritoneum unlike the rest of the spleen
Describe the relations of the spleen
Postero-inferior- kidney
superior- stomach
anterior- colon
Describe splenic rupture
tends to occur when there is localised trauma to the LUQ.
Associated with lower left rib fractures
as the spleen has a thin capsule- susceptible to injury even in the absence of damage to other structures
as the spleen is highly vascular- when ruptured- it bleeds profusely into the peritoneal cavity
should always be suspected with blunt abdominal injury
Describe splenic enlargement
The spleen is an organ of the reticulo-endothelial system (e,g leukaemia, lymphoma and certain infection) may produce lymphadenopathy and enlargement of the spleen (splenomegaly)
What is the eight segment model of the spleen based on
hepatic arterial, portal and biliary drainage of each segment
what is key to remember about the spleen
don’t need it in adult life
spleen cannot repair itself- splenectomy if damaged
