Transverse greyscale US (upper left) of the left lower quadrant of the abdomen shows a soft tissue mass demonstrating a target sign measuring less than 2 cm in diameter which on transverse color doppler US (upper right) shows normal vascularity. Sagittal greyscale US of the area shows a pseudokidney sign (below). A repeat US 15 minutes later showed the mass was gone.
Pediatric Imaging 