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Voiding Cystourethrogram

When You're Having a VCUG (Child)


A VCUG (voiding cystourethrogram) is a test that takes pictures (x-rays) of your bladder to find out if your urine is flowing backward into your ureters and kidneys. The bladder is where your urine is stored until you go to the washroom.

You may have a lot of questions about this test.

What do I have to do before the test?

You can eat and drink like you normally do before this test. If you’re taking antibiotics for a bladder or kidney infection, you must have been taking this medicine for at least 48​ hours before we can do this test.

What will I see in the x-ray room?

The room will have a really big camera over a bed. This room is often a little cool. The machines work better when the air is cooler.

The big camera is hooked up to a TV screen. The screen lets the doctor doing your test watch the inside of you.

You’ll also see a bottle full of liquid (called a contrast) hanging on a pole. A plastic tube will be connected to the bottle. This thin plastic tube is what the doctor uses to get the contrast material from the bottle into your bladder.

The contrast outlines the inside of your bladder so the doctor can “see” the inside of your bladder better.

What happens during the test?

  • You’ll lie on a table on your back.
  • The technologist will wash the tip of your penis or urethra with several pieces of cotton dipped in soap. Be sure not to touch this area until the test is over.
  • The technologist will then slide the tube a little way into your penis or urethra. This may feel a little uncomfortable—the more you relax and breathe deeply, the easier it will be. The tube will then be loosely taped to your leg so it doesn’t come out during the test.
  • The doctor will slowly let the liquid from the bottle run through the tube and into your bladder. You’ll be able to watch your bladder fill up on the TV screen. ​As your bladder fills up, you’ll feel like you have to go to the bathroom. When you don’t think that you can hold any more contrast, tell the doctor or the technologist. The doctor will tell you to hold it for just a few more seconds and take some pictures.
  • You’ll then be given a container to pee (pass water) into. The tube will come out by itself as you pee. As you pee, the doctor will take some more pictures of your bladder emptying. You must stay very still when the doctor takes the pictures.

What happens after the test?

You can go home after the test. You may feel a little sore the next few times you go to the washroom—but this will go away in a few days.

You can carry on with your day as usual.

Your family doctor will get the results of the scan in about 1 week. Please call your doctor’s office for the results.

Current as of: September 25, 2020

Author: Diagnostic Imaging, Alberta Health Services