A young man presented in urinary retention. He had suffered a renal contusion whilst playing football a week earlier which had been managed conservatively.
A large, echogenic mass was seen in the bladder. The mass was mobile, as shown by the left and right decubitus views, suggesting a blood clot secondary to the renal contusion (see case).
Bladder masses should be assessed firstly to determine if they are due to bladder wall thickening (e.g. tumour, inflammatory masses) or to intravesical masses (e.g. blood clots, infectious debris, foreign bodies (such as catheter balloons), stones). The mobility of this mass clearly showed it was intravesical and not from the bladder wall.