Liver

The liver is mainly located in the right hypochondrium and epigastric regions and extends into the left hypochondrium. The 7th to 11th ribs protect the liver

The lobes of the liver are:

  1. Right lobe

  2. Left lobe

  3. Caudate lobe

  4. Quadrate lobe

The anatomical relations of the liver can be described as:

Anteriorly: Abdominal wall and ribcage
Superiorly: Diaphragm
Posteriorly: Abdominal part of esophagus, stomach, duodenum, right colic flexure, right kidney, right suprarenal gland, and gallbladder

The ligaments of the liver can be described as:

The spaces around the liver can be described as:

  1. Hepatorenal recess (Morrison’s Pouch)- this lies between the right visceral surface of the liver and the right kidney

  2. Subphrenic recess - this lies between the liver and diaphragm

Function of the Liver

The liver is a large, solid organ that occupies the upper part of the abdominal cavity. It lies immediately adjacent to the lower surface of the diaphragm and is protected by the lower ribs.

The liver consists of a large number of lobules, each of which receives blood from both the portal vein and the hepatic artery. The liver has numerous functions, including:

  1. Metabolic processing and storage of digestive products absorbed from the intestines

  2. Manufacturing plasma proteins

  3. Synthesis of bile salts for emulsification of fats

  4. Conversion of the breakdown products of haemoglobin into bile pigments

  5. Detoxification of substances (e.g alcohol) circulating in the blood.

The liver stroma begins as a thin connective tissue capsule called the Glisson capsule that extends into the liver, around the portal triads, and around the periphery of a hepatic lobule; extends into the perisinusoidal space of Disse to surround hepatocytes; and then terminates around the central vein.

The liver is classically divided into the right and left lobes by the interlobar fissure (an invisible line running from the gallbladder to the IVC), quadrate lobe and caudate lobe.

The left lobe of the liver contains the falciform ligament (a derivative of the ventral mesentery) with the ligamentum teres (a remnant of the left umbilical vein) hanging form its free edge.

Segments and subsegments of the liver:

There are five liver segments and their boundaries are defined by the hepatic veins. The liver also has nine further subsegments.

Blood Supply.

  1. The right hepatic artery supplies the liver and its non-parenchymal structures with blood.

  2. The hepatic portal vein supplies the liver with deoxygenated blood that is rich in nutrients. The nutrients carried in the hepatic portal vein allow it to detoxify the blood and perform its functions as related to the gastrointestinal system. The hepatic portal vein is formed by the union of the superior mesenteric vein and the splenic vein.

Venous drainage:

  1. The venous drainage of the liver is to the central veins located at the center of a classic liver lobule.

  2. The central veins unite to form collecting veins which in turn unite to form hepatic veins.

  3. The hepatic veins ultimately open into the inferior vena cava.


Innervation:

It receives parasympathetic innervation from the vagus nerve via the celiac ganglion. It receives sympathetic innervation from the greater splanchnic nerve via the celiac ganglion.