“The neighboring organ (the spleen) is situated on the left hand side and is constructed with a view of keeping the liver bright and pure, like a napkin always ready prepared and at hand to clean the mirror”- Plato, Timaeus
What is Spleen?
The spleen is the largest lymphatic organ in the body. The spleen does a lot of important functions in the body like synthesis of blood and blood products, storing blood, destruction of old and ineffective red blood cells and immune function. Even though the spleen performs so many functions, it is not an essential organ for someone to stay alive. A person can live without a spleen without any ill health.
Anatomy of spleen
The spleen is located on the left side of the abdomen. It is ovoid in shape, red brown in color and is friable. It is situated just below the diaphragm. Diaphragm is a structure which separates the chest cavity from the abdomen. In the abdominal cavity, the spleen is situated deep inside near the 9th, 10th and the 11th ribs. The spleen is covered by a thin membrane called the peritoneum.
The spleen weighs about 10 grams at birth. It then enlarges and becomes about 130 grams at puberty. It diminishes in size during adult hood. It is 12 cm in length and 7 cm in breadth with the size the shape roughly corresponding to a clenched fist. The spleen is related to the following structures in virtue of its location.
- Above and the left side – diaphragm
- In front – stomach, left kidney, portion of colon, tail of pancreas
- Below – Loops of intestine
- Behind – 9th,10th and 11th ribs
Lymphoid organs are organs which are related to the immunity. The lymphoid organs in the body include Spleen, Thymus, Lymph nodes, Peyer’s Patches in the Small Intestine, Tonsils, Adenoids and the Bone Marrow. The Spleen is the largest of them all. These organs contain cells like the lymphocytes and macrophages which are related to immunity. Whenever the body is invaded by some organism, they are transported to these organs and the immune cells destroy them. The lymphoid organs are well connected with the lymphatic system. The lymphatic system consists of,
- Lymphoid organs
- Lymphatic vessels
- Lymph nodes
The lymph vessels drain lymph. Lymph is basically the fluid and protein that has been squeezed out of the blood. The Lymph ultimately drains in to the right side of the heart through the thoracic duct.
There are two blood vessels which are related to the spleen. The splenic artery supplies blood to the spleen and the splenic vein which drains the blood from the spleen. Inside the splenic tissue, two different structures can be identified (Figure 3).
- White pulp – containing lymphoid tissue which is concerned with immunity
- Red pulp – containing blood which is concerned with the destruction of the old and ineffective red blood cells
In a normal person the spleen cannot be felt. It lies deep inside. But when the spleen is involved in some disease process it enlarges considerably to be felt by placing the hands firmly on the abdomen and asking the person to breathe slowly. When the spleen is felt from the abdominal surface, it indicates that spleen has enlarged more than two times its original size.