Accessory spleen

An accessory spleen is a small nodule of splenic tissue found apart from the main body of the spleen.

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

They may resemble a lymph node or a small spleen.

They form either by the result of developmental anomalies or trauma.

They are medically significant in that they may result in interpretation errors in diagnostic imaging or continued symptoms after therapeutic splenectomy.

Polysplenia is the presence of multiple accessory spleens rather than one normal spleen.