Intravascular papillary endothelial hyperplasia of the digit: MRI features with histological correlation.

To clarify the magnetic resonance (MR) features of the pure form of intravascular papillary endothelial hyperplasia, MR images (MRIs) from five patients were retrospectively reviewed and compared with histological findings. The images showed a heterogeneous, iso- to slightly high signal intensity mass on T1-weighted images and a mass with a central heterogeneous, iso- to slightly high signal intensity area completely or incompletely surrounded by peripheral high signal intensity areas on T2-weighted images. Heterogeneous enhancement was observed after gadolinium administration. Histological studies indicated that the central heterogeneous area on T2-weighted images corresponded to thrombi (organized and/or hyalinized) and/or papillary endothelial proliferation, and also that the peripheral high signal intensity area corresponded to vascular blood space and/or papillary endothelial proliferation. The pure form of intravascular papillary endothelial hyperplasia showed relatively characteristic features on MRIs.