Table 1.
Main imaging features of adrenal lesions.
| Lesion | NCCT | MRI | Enhancement | Calcification | Hemorrhage | Necrosis |
|---|---|---|---|---|---|---|
| Adenoma | <10 HU | Loss of signal OP | RPW/APW ≥ 40/60% | − | − | − |
| Myelolipoma | <−30 HU | Loss of hyperintensity on T1-w fs | +/− | − | − | − |
| Hyperplasia | Depends on etiology | Depends on etiology | +/− | +/− | +/− | − |
| Cyst | Fluid | Hyper on T2-w Hypo on T1-w |
− | − | +/− | − |
| Schwannomas | Hypodense | Iso on T1-w Iso/Hyper on T2-w |
Inhomogeneous | +/− | +/− | − |
| Pheochromocytoma | 40–50 HU | Iso/Hypo on T1-w Hyper on T2-w |
++ | + | + | + |
| Metastasis | >10 HU | Hypo on T1-w Iso/Hype on T2w |
+/− | + | + | + |
| Carcinoma | Heterogeneous | Hypo on T1-w Hyper on T2-w |
Inhomogeneous, slow wash-out; RPW/APW < 40/60% | + | + | + |
APW: Absolute Percentage Washout; HU: Hounsfield Unit; MRI: Magnetic Resonance Imaging; NCCT: Non-Contrast CT; OP: out-of-phase; RPW: Relative Percentage Washout.