L8: Liver Anatomy Flashcards
The interior of the liver is filled with an enormous number of tiny cylinders.
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A lobule consists of a β¦β¦ in its core, surrounded by radiating sheets of cuboidal cells called β¦β¦β¦
- central vein
- hepatocytes
Each plate of hepatocytes is an β¦β¦
one or two epithelium cells.
The hepatic lobules are separated byβ¦β¦..
sparse CT stroma.
In cross sections, the stroma is especially visible in the triangular areas β¦β¦
where three or more lobules meet.
- Here, there is often a hepatic triad of two blood vessels and a bile ductule.
- The blood vessels are small branches of the hepatic arteries and hepatic portal vein.
β¦..
Def of Hepatic Sinusoid
The spaces () the plates are blood-filled channels.
Lining of Hepatic Sinusoid
Lined by a fenestrated epithelium that separates the hepatocytes from the blood cells.
Pathway of Bile Seretion in the liver
structure of Hepatic Sinusoid
- They contain phagocytic cells called hepatic macrophages (Kupffer cells), which remove bacteria and debris from the blood.
- The hepatocytes secrete bile into the bile canaliculi (narrow channels) between the plates of the lobules β to the small bile ductules between lobules β ductules lead ultimately to the right and left hepatic ducts, which exit the inferior surface of the liver
Site of the Liver
The Anatomical Liver Lobes are separated by β¦β¦.
The right lobe contains two small lobes: Quadrate lobe & Caudate lobe.
- The attachment of the falciform ligament on anterior and superior surfaces.
- The fissure for ligamentum teres on the inferior surface.
- The fissure for ligamentum venosum on the posterior surface.
Surfaces of The Liver
Relations to the Anterior surface of the liver
Relations to the Superior surface of the liver
Relations to the Right lateral surface of the liver
Relations of the Posterior surface of the liver
Rekations of the Visceral (inferior) surface of the liver
Relations of the quadrate lobe
Fissures of the Liver
- Three major fissures (main, left, and right portal fissures), contain the three main hepatic veins.
- Three minor fissures (umbilical, venous and fissure of Gans) are visible as physical clefts of the liver surface.
Major fissures of the liver
- Main portal fissure
- Right portal fissure
- Left portal fissure
Another name for Main portal fissure
Cantlieβs line
Describe Main portal fissure
- It extends from the midpoint of the gallbladder fossa to the midpoint of the inferior vena cava
Content of Main portal fissure
contains the middle hepatic vein.
Significance of Main portal fissure
separates the liver into right and left hemi-livers
Significance of Right portal fissure
- It divides the right hemi-liver into posterior and anterior sectors.
Content of Right portal fissure
It contains the right hepatic vein.
Content of Left portal fissure
- It contains the left hepatic vein
Minor fissures of the liver
- Umbilical fissure
- Venous fissure
- Fissure of Gans
what is another name of Umbilical fissure?
Fissure for the ligamentum teres
Signiicance of Umbilical fissure
- Separates segment III from segment IV within the left medial sector
Content of Umbilical fissure
- It contains a major branch of the left hepatic vein (the umbilical fissure vein).
Attachment of Umbilical fissure
It is marked anteriorly by the attachment of the falciform ligament and inferiorly by the ligamentum teres
Another name for Venous fissure
Fissure for the ligamentum venosum
what is the Venous fissure a contuity of?
Is in direct continuity with the umbilical fissure on the undersurface of the liver.
Content of Venous fissure
It contains the ligamentum venosum (The obliterated ductus venosus)
Site of Fissure of Gans
Lies on the undersurface of the right lobe of the liver behind the gallbladder fossa.
The liver is divided into β¦. surgical segments.
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This segmentation is based on:
what are hepatic veins?
Right vβ right portal fissure
Middle vβ main portal fissure
Left vβ left portal fissure.
The Liver is divided into 2 equal right & left surgical lobes by β¦..
Cantlieβs plane (main portal fissure).
what divides The right surgical lobe?
What Divides The Left surgical lobe?
Segment I (caudate lobe = spigelβs lobe)
Def of Porta Hepatis
The hilum of the liver
Site of Porta Hepatis
Posterior part of the inferior surface () caudate and quadrate lobes
Blood Supply of Liver
- The hepatic artery (30 %)
- The portal vein (70%)
Contents of Porta Hepatis
The left hepatic artery supplies the β¦..
left half of liver (II, III, and IV).
The right hepatic artery supplies the β¦β¦
right half of liver (V, VI, VII, and VIII)
The proper hepatic artery bifurcates β¦β¦
into right and left hepatic arteries outside liver
Small branches from near the bifurcation of the proper hepatic artery β¦β¦.
also supply segment I.
A middle hepatic branch may arise from either right or left hepatic arteries after bifurcation.
β¦
Bifurcation of The portal vein
In the hilum of the liver, the main portal vein bifurcates into: Right Portal Vein & Left Portal Vein
Characters of Right Portal Vein
Short oblique
Course of Right Portal Vein
Enters hepatic parenchyma immediately and is quick to divide into a right anterior and posterior vein
What Does Right Portal Vein supply?
- Right anterior V β segment V, VIII
- Right posterior V β segments VI, and VI
Character of Left Portal Vein
Longer, more transverse, and more superficial
Course of Left Portal Vein
Courses to the umbilical fissure to give off medial branches and lateral branches
What Does the Left Portal Vein supply?
- Medial branches β segment IV
- Lateral branches β segments II, and III.
Both right and left veins give off small branches β¦β¦.
to dually supply segment I
Venous Drainage of The Liver
The 3 major hepatic veins carry blood from the liver to the β¦β¦
IVC
Site of Left hepatic vein
The left portal fissure
Drainage of Left hepatic vein
Segments II, III and, occasionally, IV.
Termination of Left hepatic vein
Middle V usually joins the left hepatic vein and terminates in the inferior vena cava as a short common trunk
Site of Middle hepatic vein
The main portal fissure
Drainage of Middle hepatic vein
The central part of the liver (segments IV, V and VIII)
Termination of Middle hepatic vein
Middle V usually joins the left hepatic vein and terminates in the inferior vena cava as a short common trunk
Middle hepatic vein ends as a single trunk in the inferior vena cava in fewer than 10% of individuals.
β¦
Site of Right hepatic vein
The right portal fissure
Drainage of Right hepatic vein
The whole of segments VI and VII, and variable proportions of segments V and VIII.
Termination of Right hepatic vein
The right anterior wall of IVC.
Right hepatic vein is the largest and the longest
β¦.
Segment I is drained through β¦..
at least 2 constant veins directly into IVC
Lymphatics of the posterior part of the liver
Follow IVC to end in the diaphragmatic LNs around the upper end of IVC in the thorax.
Lymphatics of the remaining part of the liver
Follow hepatic artery β the celiac LNs around celiac trunk β Cisterna chylii β thoracic duct.
Site of nerve supply of the Liver
From hepatic plexus at porta hepatic
sympathetic Supply Of the Liver
Sympathetic fibers from greater splanchnic nerve.
Parasympathetic Supply Of the Liver
Parasympathetic fibers from hepatic branch of vagus.
Peritoneal Ligaments of the Liver
- Falciform ligaments
- Coronary Ligaments
- Triangulars Ligaments
- Lesser Omentum
Def of Falciform Ligament
Fold of peritoneum, which connects anterior abdominal wall to the liver.
Apex of Falciform Ligament
At the back of the umbilicus.
Base of Falciform Ligament
Superior border of Falciform Ligament
Attached to the anterior abdominal and the under surface of the diaphragm
Inferior border of Falciform Ligament
Free and concave
VIP
The Rt & Lt layer of Falciform Ligament
VIP
- contents of Falciform Ligament
Def of Coronary Ligament
Fold of peritoneum, which connects the diaphragm on to the superior and posterior surfaces of the right lobe of the liver.
Layers of Coronary Ligament
Formed of superior and inferior layers
Superior & Inferior reflection of Superior Coronary Ligament
Superior & Inferior reflection of Inferior Coronary Ligament
What is found between both superior & Inferior Coronary Ligaments?
A large triangular area of liver devoid of peritoneal covering called βbare areaβ of the liver
Termination of both superior & Inferior Coronary Ligaments on the Right
The two layers of the coronary ligament converge laterally to form the right triangular ligament.
Termination of both superior & Inferior Coronary Ligaments on The left
The two layers become closely applied and form the left triangular ligament.
Parts of Triangular Ligament
- left triangular ligament
- right triangular ligament
Def of Lt. Triangular Ligament
Is a double layer of peritoneum that extends over the superior border of the left lobe of the liver.
Anterior Leaf of Lt. Triangular Ligament
Medially, it is continuous with the left layer of the falciform ligament
Posterior Layer of Lt. Triangular Ligament
Medially, it is continuous with the left layer of the lesser omentum.
Def of right triangular ligament
a short structure that lies at the right lateral limit of the βbare areaβ of the liver
what does right triangular ligament represent?
It represents the meeting of the
two layers of the coronary ligament.
Superior attachment of Lesser Omentum
- Lips of the porta hepatis.
- Bottom of the fissure for ligamentum venosum.
Inferior attachment of Lesser Omentum
- Lesser curvature of the stomach.
- Upper border of the first inch of the duodenum
Attachment of the Lt side of Lesser Omentum
To the diaphragm between the liver and the lower end of the esophagus.
Attachment of the Rt side of Lesser Omentum
- Form the free margin of the lesser omentum.
- It forms anterior boundary of the opening into the lesser sac.
Except over its bare area (in direct contact with the right hemidiaphragm), the serous surfaces of the liver and diaphragm are side by side and separated by a potential space
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Suprahepatic space is divided into RT and LT spaces by β¦β¦.
falciform ligament.
What are two suprahepatic spaces?
Left & Right suprahepatic space
Site of Lt suprahepatic space
Site of RT suprahepatic space
what are two infrahepatic spaces?
- The right infrahepatic space (hepatorenal space, pouch of Morison)
- The left infrahepatic space.
Other names of The right infrahepatic space
(Hepatorenal space, pouch of Morison)
Superior & Anterior realtions of The right infrahepatic space
- The right lobe of the liver.
- It is limited superiorly by the inferior layer of the coronary ligament.
Posterior relations of The right infrahepatic space
by the anterior surface of the upper pole of the right kidney.
Lateral relations of The right infrahepatic space
Right lateral abdominal wall.
Inferior relations of The right infrahepatic space
- Opens into the general peritoneal cavity.
- Partly limited by the hepatic flexure, transverse mesocolon, 2nd part of the duodenum, and head of pancreas
Medical Importance of The right infrahepatic space
- The hepatorenal pouch (of Morison) is the most dependent in the supine position.
- It is a site where a pathological fluid collection may develop.
Divisions of The Left infrahepatic space
Study Extraperitoneal spaces
Parts of Extrahepatic biliary system
- Gall bladder.
- Duct System.
1) Common hepatic Duct.
2) Cystic Duct.
3) CommonBileDuct.
Site of Gall Bladder
Fossa of gall blader within the substance of liver.
Shape of Gall Bladder
Pear shaped
Parts & Peritoneal Covering of Gall Bladder
Relations of the fundus of Gall Bladder
Arterial supply of Gall Bladder
Cystic artery.
- From RT hepatic art.
- Passes behind the cystic duct.
Relations of the body & Neck of Gall Bladder
Venous drainage of Gall Bladder
Cystic vein.
- Drains into the right branch of portal vein.
Lymphatic drainage of Gall Bladder
Lymph nodes at the porta hepatis
Another name of Calotβs Triangle
Cystohepatic Triangle
Def of Calotβs Triangle
Small anatomical space located at the porta hepatis of the liver.
Boundaris of Calotβs Triangle
Contents of Calotβs Triangle
Medical Importnace of Calotβs Triangle
The triangle of Calot is of clinical importance during laparoscopic cholecystectomy
Duct system of biliary tree
1) Cysticduct.
2) Common hepatic duct.
3) Commonbileduct
Characters of Cystic duct
Begging & Termination of Common hepatic duct
- Formed by union of right & left hepatic ducts at the porta hepatis.
- Ends by joining cystic duct to form the common bile duct
Length of Common bile duct
7.5 cm
Formation of Common bile duct
By union of cystic & CHD at porta hepatis.
Site & Relations of Common bile duct
Common bile duct
- At free border of lesser omentum
Left: hepatic artery.
Posteriorly: portal vein.
Common bile duct
- Behind the 1st part of duodenum
Left: gastroduodenal artery.
Posteriorly: portal vein.
Common bile duct
- Behind head of pancreas
Posteriorly: IVC
Termination of Common bile duct
- Unite with major pancreatic duct in the wall of duodenum to form ampulla of Vater.
- Opens on the major duodenal papilla.
- Guarded by sphincter of Oddi.
Done
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