T1-weighted precontrast image (A) demonstrates a dilated duct containing proteinaceous or hemorrhagic debris (arrow). Following IV contrast, an enhancing mass is seen contiguous to the dilated duct (B, arrowhead). This was biopsied under MR guidance and shown to represent an intraductal papilloma.
MRI: magnetic resonance imaging; IV: intravenous; MR: magnetic resonance.
