Bladder pseudomass following cystography-related bladder trauma.

Transient sonographic abnormalities of the urinary bladder in children can be identified immediately after performance of voiding cystourethrography. Both cystic and solid masses may be mimicked by transient hematuria induced by minor, cystography-related trauma. After the bladder has been emptied and refilled, reexamination shows prompt resolution of these pseudo-masses.