Exophytic renal angiomyolipoma

1. B-mode ultrasound image demonstrates an exophytic hyperechoic mass with smooth external margin arising from the right kidney. The exophytic renal mass makes an angular interface with the renal parenchyma.
2. Color Doppler ultrasound image demonstrates two distinct vessels entering the exophytic mass. The vessels show opposite color Doppler flow and are likely to represent an arteriole and venule pair.

Non-contrast CT images show foci of fat density (<20 HU) within the smooth marginated exophytic mass which is isodense to renal parenchyma. 

Contrast CT images, corticomedullary phase, again illustrate the angular interface of the exophytic renal mass with the renal parenchyma.