what is vcug used for
Voiding Cystourethrogram (VCUG). A VCUG, or a voiding cystourethrogram, is a minimally invasive test that uses a special x-ray technology called fluoroscopy to visualize your child's urinary tract and bladder. A VCUG can help: 1  diagnose vesicoureteral reflux-a condition in which urine flows the wrong way, from the bladder back up to the kidneys.