LIVER INFORMATION
Facts
What it is and where it is
The liver is the largest internal organ of the body weighing approximately 1.3kgs in women and 1.5kgs in men.
It sits under the rib cage predominantly on the upper right side of the abdomen . The liver is made up of two lobes with the left lobe and right lobe divided by a large section of tissue (ligament) that anchors it in place. The right lobe makes up about 2/3rds of the liver and incorporates 2 further lobes (the quadrate and caudate lobes) whilst the left lobe makes up the remaining 1/3rd of the liver volume. Surgically the liver is seen in terms of 8 segments which are known as Couinauds segments and these determine surgical division, if and when this is needed.
The liver is connected directly to the gall bladder and the pancreas.
The liver is linked to both the gall bladder and pancreas via the biliary tree with the gall bladder acting as a storage and concentration vessel for bile and the pancreas being an organ that makes and secretes substances to regulate blood sugar levels as well as producing enzymes that help digestion.
The liver’s blood supply consists of the Hepatic Portal Vein (HPV) which takes blood to the liver and the hepatic vein (HV) which takes the blood from the liver and returns it to the main vein that leads to the heart.
The liver receives the enormous volume of blood that passes through it (1.5 litres per minute) from the hepatic portal vein and the hepatic artery which flow into the liver via an area called the Porta Hepatis, this area is located on the under side of the organ. The portal vein is a very large vein which receives large volumes flowing into it from the circulation around the bowel and spleen. This means that nearly everything that you put into your body is transported through the lining of the bowel into the portal vein and taken to the liver before it can affect any other organs of the body. This is important as it is the liver that works to ensure that harmful substances that you may eat or drink are made harmless and any substances that are needed for health are absorbed properly or converted and stored within the body, whilst any excess of substances are transported either in the bile or to the kidneys to be removed.
The bile duct system starts within the liver (termed intra hepatic) and extends outside of the liver (termed extra hepatic) to involve both the gall bladder and pancreas.
The biliary system is often referred to by the simple term ‘duct’ with the particular name of each duct pertaining to its location e.g. hepatic ducts in the liver, cystic duct from the gall bladder etc. Bile is formed within the liver cells and then flows out of the liver using the hepatic ducts to join the cystic duct and the pancreatic duct before exiting into the duodenum (first part of the intestine after the stomach) via a sphincter, this is a term that describes a hole surrounded by muscle that can narrow or expand as needed.