FNAs are difficult to interpret. • Dynamic gadolinium-enhanced MRI may be helpful in combination with

the CT scan.

How do you diagnose adrenal lesions on a CT scan?

• They are diagnosed by the Hounsfield units. • The radiodensity of distilled water at standard temperature and pressure is 0. • Other values include bone: 1000; muscle: 10-40; fat: −50-100; air: −1000. • The CT should report the Hounsfield units of the lesion. • If value is <10 μ, malignancy is unlikely. • A benign lesion should have >60% contrast washout at 15 min in an

IV-contrast enhanced CT.