Imaging of bilateral ureteropelvic junction laceration from blunt trauma.

Bilateral ureteropelvic junction (UPJ) injury from blunt abdominal trauma is rare, with only seven previously reported cases, all of which were complete avulsions. Early and delayed computed tomography (CT) for visualization of the nephrographic and excretory renal phases, respectively, is essential to distinguish parenchymal from collecting system injury. Once UPJ injury is detected by CT, differentiation between laceration and avulsion is mandatory since laceration is treated nonoperatively, whereas avulsion requires surgical repair.