Thoracic extramedullary hematopoiesis: evaluation by conventional radiology and computed tomography.

4 cases of extramedullary hematopoiesis (EH) in the posterior mediastinum in patients affected with serious chronic anemia are presented. The contribution of conventional radiology and computed tomography (CT) to the assessment of an exact diagnosis, is discussed. The CT images are above all characterized by the presence of typical bilateral, asymmetrical paravertebral hyperdense masses (about 45 HU). Besides, a striated aspect of the vertebral bodies is common. For a rather sure diagnosis of EH in patients with chronic anemia, a conventional chest X-ray and CT of the thorax is sufficient. Biopsy and thoracotomy should be avoided.