Radiographic manifestations of congenital anomalies of the lower urinary tract.

The evaluation of anomalies of the lower urinary tract (ureter, bladder, and urethra) requires high quality ultrasonography, voiding cystourethrography, and, occasionally, intravenous urography and contrast sinography. Infants with these anomalies present because of abnormal intrauterine ultrasonographic examinations, urinary tract infections, or obvious external malformations. With a solid embryologic knowledge of the development of the lower urinary tract the radiologist can tailor the imaging procedures to demonstrate almost all aspects of the anomaly and the presence or absence of frequently associated malformations.