Splenomegaly is defined as enlargement of the spleen. On ultrasound, the spleen is measured along its longest craniocaudal axis; a length greater than 13 cm in adults is generally considered enlarged. The normal spleen is homogeneously echogenic and roughly triangular or crescentic in shape. Splenomegaly has many causes including portal hypertension, lymphoma, hematologic disorders, infection, and infiltrative diseases. Ultrasound also evaluates splenic echotexture and detects focal lesions or splenic infarcts.