Minimizing the Utilization of Voiding Cystourethrography for Patients With Antenatal Hydronephrosis

Investigators conducted a previous retrospective study to evaluate other possible findings on
ultrasound that may better predict reflux. Investigators found that if a postnatal ultrasound
showed any of the three findings of hydroureter, duplication or dysmorphic kidney, then the
odds ratio of detecting reflux was 8.07 (95%CI 3.86, 16.87). The purpose of this study is to
perform a randomized prospective study to validate this retrospective study. Investigators
hypothesis is that patients with hydronephrosis alone will be more likely to have negative
VCUG studies; hence obtaining a VCUG for this indication may not be warranted.

Inclusion Criteria:

- Patients with a history of antenatal hydronephrosis who have a post-natal ultrasound
demonstrating hydronephrosis alone and no other abnormalities

Exclusion Criteria:

- Patients with a post-natal ultrasound demonstrating bilateral hydronephrosis

- Patients with a history of posterior urethral valve or when a valve is suspected

- Patients who have hydronephrosis on ultrasound as well as other findings including
duplication, hydroureter, dysmorphic kidneys, or bladder abnormalities