Thoracic splenosis after blunt trauma: frequency and imaging findings.

Abstract

Thoracic splenosis is an uncommon sequela of simultaneous splenic and diaphragmatic injury. The aim of this prospective study was to evaluate the prevalence of thoracic splenosis in 17 subjects who had sustained splenic and diaphragmatic injury and to describe the CT and MR features of thoracic splenosis. All patients had 99mTc-RBC scintigraphy. Subjects with radionuclide uptake in the thorax were further examined with radiography, CT, and MR imaging of the chest. Three subjects (18%) had evidence of ectopic splenic activity in the left side of the thorax. The CT features consisted of one pleural nodule and two pleural masses. The MR appearance of the ectopic splenic tissue was similar to that of normal spleen. Thoracic splenosis occurs with moderate frequency after combined splenic and diaphragmatic injury. The CT appearance is that of pleural masses or nodules. The MR appearance is relatively similar to that of normal spleen.