Robert L. Lebowitz, M.D. Children' s Hospital, Harvard Medical School Boston, Massachusetts

Catheterization for VCUG showed that the catheter coiled in the sphincteric ureterocele and not in the bladder (figure 1). Contrast material filled the upper pole ureter and calyces (figure 2), and then a small amount of contrast material leaked out of the ureterocele and filled a little of the bladder around the ureterocele (figure 3,4). The eccentric position of the ureterocele on the right side of the pelvis, and the tight coil of the catheter before contrast was introduced, also on the right side of the pelvis (figure 5), were the initial suggestions that is was the ureterocele that was filling and not the bladder. Figure 6 is a schematic drawing of a sphincteric ureterocele.