Pediatric Radiology > Genitorinary > Hydronephrosis > Posterior Urethral Valves

Posterior Urethral Valves

Bilateral hydronephrosis can be caused by posterior urethral valves (PUV). Posterior urethral valves are abnormal folds in the posterior urethra resulting in a functional obstruction. PUV are best demonstrated with a VCUG. The VCUG shows dilatation and elongation of the posterior urethra with a normal anterior urethra. The valves can be seen as transverse filling defects. The bladder will be heavily trabeculated secondary to the obstruction.
VCUG of posterior ureteral valves	VCUG of posterior ureteral valves
US of hydronephrosis caused by PUV	US of hydronephrosis caused by PUV