The role of the spleen is completely different in West vs. Eastern medicine.

  • In western physiology, the spleen is a large, vascular, lymphatic organ. It acts as a reservoir and filters the blood. It also plays a role in making blood early on in life.
  • TCM does not indicate that it does not perform these roles. It does assists with digestion, blood coagulation and fluid metabolism in the body.

The spleen is the primary organ responsible for digestion, its main function is to transform food into essence used for Qi and blood transformation. Once the ingested food and liquids get into the body, the spleen extracts a pure nutritive essence from them. This pure nutritive essence is used for Qi production, blood and body fluids, which the spleen then transports throughout the body. Liquids extracted as pure nutritive essence are sent upwards to the lung for dissemination and redistribution. Some of this Qi is diverted and will descend to the kidney and bladder to be excreted as urine. 

Definition of liver-spleen scan - NCI Dictionary of Cancer Terms ...