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Voiding Cystourethrogram (VCUG): About This Test

What is it?

A voiding cystourethrogram (say "sis-toh-you-REE-throh-gram") is a test that is done to see if there are problems with the urinary system. The test uses contrast fluid and X-rays so the doctor can see the size of the bladder and how the bladder fills and drains.

Why is this test done?

This test is done to:

  • Find the cause of urinary problems. These include repeated urinary tract infections and not being able to control when you urinate (urinary incontinence).
  • Check for vesicoureteral reflux, which means urine backs up toward the kidneys from the bladder instead of going through the urethra and out of the body.
  • Check for structural problems of the bladder and urethra.
  • Follow up on other problems found during a different test such as a CT scan of the urinary system.

How do you prepare for the test?

Having a test can be stressful. This information will help you understand what you can expect. And it will help you safely prepare for your test.

Preparing for the test

  • Tell your doctor if you are allergic to iodine. Iodine is usually used in the contrast material that the doctor will put in your bladder.
  • Tell your doctor if you are or might be pregnant. Your doctor may not do the test if you are pregnant. That's because the X-rays could harm an unborn baby.
  • Understand exactly what procedure is planned, along with the risks, benefits, and other options.
  • Tell your doctor ALL the medicines and natural health products you take. Some may increase the risk of problems during your procedure. Your doctor will tell you if you should stop taking any of them before the procedure and how soon to do it.
  • If you take a medicine that prevents blood clots, your doctor may tell you to stop taking it before your procedure. Or your doctor may tell you to keep taking it. (These medicines include aspirin and other blood thinners.) Make sure that you understand exactly what your doctor wants you to do.

How is the test done?

  • The technologist or nurse will ask you to take off all or most of your clothes and provide you with a gown. Then you will cover yourself with a cloth or paper covering.
  • You will urinate just before the test starts.
  • You will lie on your back on an X-ray table, and a standard X-ray will be taken of your belly and pelvic area.
  • Your genital area will be cleaned and covered with towels. A flexible, thin tube will be inserted through your urethra into your bladder. This tube is called a catheter.
  • The doctor will put a liquid into your bladder through the catheter. This liquid is called contrast material. It shows up well on X-ray pictures.
  • X-rays will be taken while your bladder is filled with liquid and as the liquid drains out. You may be asked to stop urinating, change positions, and start urinating again.
  • Your bladder may be filled a second time. The catheter may slip out by itself while your bladder is draining. If not, it will be removed.
  • Once your bladder is empty, a final X-ray is usually taken.

How does having a voiding cystourethrogram (VCUG) feel?

This test isn't painful, and you won't feel anything when the X-rays are taken.

You may find it somewhat uncomfortable when the catheter is inserted and while it's in place. You will have a feeling of fullness in your bladder and an urge to urinate when the contrast liquid fills your bladder.

You may be a little sore afterward from the catheter. If so, soaking in a warm tub bath may help.

What happens after the test?

  • You may get some results right after the test. You should get final results in 1 to 2 days.
  • You will probably be able to go home right away.
  • You can go back to your usual activities right away.
  • You may need to urinate often and may feel some burning during and after urination for a day or two.
  • A pinkish tinge to the urine is common for several days after this test.
  • Drinking fluids may help prevent pain when you urinate and a urinary tract infection.

Follow-up care is a key part of your treatment and safety. Be sure to make and go to all appointments, and call your doctor or nurse advice line (811 in most provinces and territories) if you are having problems. It's also a good idea to keep a list of the medicines you take. Ask your doctor when you can expect to have your test results.

Where can you learn more?

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