Myelolipoma of the adrenal gland: sonographic and CT features.

The radiologic findings in 13 patients with pathologically proved adrenal myelolipomas were reviewed. All lesions involved the right adrenal gland; they ranged from 2 to 9 cm in diameter. Sonograms showed hyperechoic tumors in 11 cases (five homogeneous, six heterogeneous). Two myelolipomas composed primarily of myeloid tissue were hypoechoic. A propagation speed artifact was seen in seven lesions, all of which were composed primarily of fat and larger than 4 cm. CT identified fat-density tissues in all lesions. Contrast-enhanced CT showed positive attenuation values in the two predominantly myeloid tumors. CT appears to be sensitive for the diagnosis of adrenal myelolipomas. However, precontrast images are required to avoid errors.