The purpose of our educational exhibit is to review the magnetic resonance imaging (MRI) findings of various adrenal pathologies. After reviewing this exhibit, the reader will be able to recognize (1) the distinguishing characteristics of various adrenal lesions, (2) mimics of adrenal pathology, and (3) the strengths and weaknesses of MRI for evaluating adrenal lesions.

The adrenals are a common site of disease. Adrenal lesions are increasingly discovered on cross sectional imaging performed for another purpose (i.e., incidentalomas). The adrenals are usually well visualized on abdominal MRI. A systematic approach to evaluating adrenal lesions on specific MRI pulse sequences leads to increased diagnostic accuracy and confidence. In this educational exhibit we present a series of cases showing the MRI appearance of various adrenal pathologies related to trauma, infection, benign and malignant neoplasms, and other etiologies. The text highlights the key...

Group 1: Pathognomonic adrenal lesions Case 1: History withheld.What is your Diagnosis? Diagnosis: Adrenal adenoma Discussion: Adenomas are common benign tumors of the adrenal cortex that are usually found incidentally. Most adenomas (90%) are nonfunctioning. Adenomas occasionally produce excess aldosterone (so called aldosteronomas), which causes secondary hypertension (Conn syndrome). Adenomas contain intracytoplasmic lipid due to steroid production. MRI chemical shift imaging (CS-MRI), which consists of in-phase and out-of-phase (OP) T1-weighted images, can detect even a small amount of intracytoplasmic lipid that may not be detectable...

MRI plays an important role in evaluating adrenal lesions, narrowing the differential diagnosis, and sometimes offering a specific diagnosis. Imaging frequently guides the clinical management of adrenal lesions. Biopsy is reserved for cases with indeterminate imaging features when there is suspicion of malignancy. The radiologist who is familiar with the MRI appearance of adrenal pathologies within the context of pretest probability is equipped to add value to patient care.

Shafik N. Wassef, MD Resident Physician, PGY4 Vice President, House Staff Council University of Iowa American Board of Radiology, Initial Certification Advisory Committee Radiological Society of North America (RSNA), Resident &Fellow Committee Society of Interventional Radiology (SIR),Resident Fellow Section Interest: Interventional and Diagnostic Radiology. email: [email protected] Alan H. Stolpen, MD, PhD, FACR Past President, Iowa Radiological Society Associate Professor of Radiology Director of MRI University of Iowa Health Care email:[email protected]

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