[Diagnostic imaging of splenic disease]

Primary diseases of the spleen are relatively rare. More frequently, the spleen is involved secondarily in hematological, oncological, infectious, immunological, vascular, and other systemic diseases. The spleen is the most commonly injured organ in blunt abdominal trauma. Anatomical and physiological basics are explained, in addition to embryological facts with resulting abnormalities, such as accessory and "wandering" spleen, and polysplenia. The most frequent primary and secondary diseases of the spleen, including rare diagnoses, are presented and illustrated. Hemangioma represents the most common primary benign tumor, and lymphoma the most common primary malignant tumor of the spleen. Diagnostic imaging does not a allow safe differentiation between Hodgkin's and non-Hodgkin's lymphoma. One section deals with the clinical value and diagnostic workup of incidentally detected lesions. Simple cysts and calcifications need neither clarification nor a follow-up examination. Atypical cysts should be controlled within 3-6 months. Additional clarification using CT or MRT should be reserved for cases with a strong suspicion of clinically relevant primary or secondary splenic disease.