#LIVER #anatomy #physiology
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anatomy and physiology of the liver
The liver is a big, advanced organ with quite a few features, which embody metabolic and hematologic regulation and bile manufacturing. It’s the largest organ of the
stomach, occupying a significant portion of the best hypochondriac and epigastric areas, typically extending
into the left hypochondriac and umbilical areas. The
liver is bordered superiorly, laterally, and anteriorly by
the best hemidiaphragm. The medial floor
is bordered by the abdomen, duodenum, and transverse
colon; the inferior floor is bordered by the hepatic
flexure of the colon; and the posterior floor is bordered by the best kidney . The liver
is surrounded by a powerful connective tissue capsule (Glisson’s capsule) that provides form and stability to the gentle
hepatic tissue. It’s also completely lined by peritoneum
aside from the gallbladder fossa, the floor apposed to
the inferior vena cava (IVC), and the naked space, which is
the liver floor between the superior and inferior coronary ligaments. The liver is connected to the diaphragm
through the best and left triangular ligaments, that are
extensions of the coronary ligaments
Floor Anatomy
The liver may be divided into lobes in accordance with floor
anatomy or into segments in accordance with vascular provide.
The 4 lobes generally used for reference based mostly on
floor anatomy are the left, proper, caudate, and quadrate. The left lobe is essentially the most anterior of the liver lobes,
extending throughout the midline. The correct lobe is the most important
of the 4 lobes and is separated from the left lobe by the
interlobar fissure. The smallest lobe is the caudate lobe,
which is positioned on the inferior and posterior liver floor, sandwiched between the IVC and the ligamentum
venosum. The ligamentum venosum is a fibrous remnant
of the ductus venosum of the fetal circulation. The quadrate lobe is positioned on the anteroinferior floor of the
left lobe between the gallbladder and the spherical ligament.
The hilum of the liver, the porta hepatis, is positioned on the
inferomedial border of the liver. It’s the central location
for vessels to enter and exit the liver
Throughout the liver there are a number of fundamental grooves or fissures which can be helpful in defining the lobes and bounds of the hepatic segments. The fissure for the spherical
ligament divides the left hepatic lobe into medial and
lateral segments. The fissure for the ligamentum venosum separates the caudate lobe from the left lobe, and
the transverse fissure (portal) comprises the horizontal
parts of the best and left portal veins. The interlobar fissure (fundamental lobar fissure), an imaginary line drawn
by the gallbladder fossa and the center hepatic
vein to the IVC, divides the best from the left lobes of
the liver
Segmental Anatomy
Present follow favors the division of the liver into eight
segments, in accordance with its vascular provide, which may help
in surgical resection. In line with the French anatomist
Couinaud, the liver may be divided into segments based mostly on
the branching of the portal and hepatic veins. The three
fundamental hepatic veins divide the liver longitudinally into 4
sections . The center hepatic vein divides the
liver into proper and left lobes. The correct lobe is split into
anterior and posterior sections by the best hepatic vein,
and the left lobe is split into medial and lateral sections
by the left hepatic vein. Every part is then subdivided
transversely by the best and left portal veins, creating
eight segments. Every phase may be thought-about functionally unbiased; every has its personal department of the hepatic
artery, portal vein, and bile duct and is drained by a department
of the hepatic veins
The liver receives nutrient-rich blood from the gastrointestinal tract through the portal hepatic system
The most important vessel of this technique is the
portal vein, which is fashioned within the retroperitoneum by
the union of the superior mesenteric and splenic veins,
posterior to the neck of the pancreas on the portal splenic
confluence .
It passes obliquely to the
proper, posterior to the hepatic artery throughout the lesser
omentum, and enters the liver on the porta hepatis
On the porta hepatis, the
portal vein branches into proper and left fundamental portal veins
that then observe the course of the best and left hepatic
arteries. The correct fundamental portal vein first sends branches
to the caudate lobe (phase I) after which divides into
anterior and posterior branches that subdivide into superior and inferior branches to provide the best lobe of the
liver (segments V, VI, VII and VIII). The left fundamental portal
vein initially programs to the left, then turns medially
towards the ligamentum teres. It branches to provide
the lateral segments (segments II and III) of the left lobe
and the superior and inferior sections of phase I
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