Adrenal Imaging: Magnetic Resonance Imaging and Computed Tomography

The adrenal glands are located superior to the kidneys and play an important role in the endocrine system. Each adrenal gland contains an outer cortex, responsible mainly for the secretion of androgens and corticosteroids, and an inner medulla, which secretes epinephrine and norepinephrine. Here, we review the anatomy of the adrenal glands and explain the current imaging modalities that are most useful for the assessment of the various conditions--both benign and malignant--that can affect these glands. As adrenal lesions are often identified incidentally on cross-sectional imaging performed for other reasons, the management of such adrenal 'incidentalomas' is also discussed. In many cases, adrenal lesions have distinctive imaging features that allow for a full characterization with noninvasive techniques. In some cases, invasive studies such as adrenal vein sampling or adrenal biopsy become necessary. This review should give the reader a wide overview of how various imaging techniques can be useful in the assessment of adrenal pathology.