Myelolipoma: radiologic findings in seven patients.

Myelolipomas are rare, non-functioning, benign tumors which occur both in the adrenal gland and in various extra-adrenal locations, particularly presacrally. We report the computed tomographic (CT) and ultrasonographic (US) findings in seven patients with pathologically proven myelolipomas. Magnetic resonance (MR) imaging was also obtained in one. Our series includes one patient with bilateral myelolipomas, one with a presacral myelolipoma, and one with a calcified myelolipoma. Radiographic findings can suggest the diagnosis. A characteristic mass is lucent on plain films, is echogenic on US, shows fat attenuation on CT, is avascular at angiography, and has a signal intensity similar to that of fat on T1-weighted MR images. However, the absence of fat can render imaging findings nonspecific. Percutaneous needle biopsy is a simple, safe, effective way to establish the diagnosis when imaging features are not typical.