accessory spleen
splenunculus
supernumerary spleen
splenule

In some cases, one or more accessory spleens are discovered and also removed during surgery.

Accessory spleen: About 10% of people have a small extra spleen.

Polysplenia is a congenital disease manifested by multiple small accessory spleens.

Accessory spleens are found in approximately 10 percent of the population and are typically around 1 centimeter in diameter.

The most common locations for accessory spleens are the hilum of the spleen and adjacent to the tail of the pancreas.

An accessory spleen (supernumerary spleen, splenule, or splenunculus) is a small nodule of splenic tissue found apart from the main body of the spleen.

If splenectomy is performed for conditions in which blood cells are sequestered in the spleen, failure to remove accessory spleens may result in the failure of the condition to resolve.

During medical imaging, accessory spleens may be confused for a enlarged lymph nodes or neoplastic growth in the tail of the pancreas, gastrointestinal tract, adrenal glands or gonads.

Accessory spleens may be formed during embryonic development when some of the cells from the developing spleen are deposited along the path from the midline, where the spleen forms, over to its final location on the left side of the abdomen by the 9th-11th ribs.