Voiding Cystourethrogram

What is a voiding cystourethrogram?

A voiding cystourethrogram (VCUG) is an imaging study that helps us evaluate your child’s bladder, urethra, and kidneys. Doctors often request this study for children who have frequent urinary tract infections. It is also used to detect reflux, a condition where urine goes back up to the kidneys instead of flowing out through the urethra.

A VCUG is a fluoroscopy exam. This type of X-ray imaging enables us to capture a real-time, moving images, much like an X-ray movie. To make this image we use a specialized X-ray machine called a fluoroscope. To highlight the bladder we use a catheter to fill your child's bladder with a liquid contrast agent, or dye.

How can I help my child prepare for the exam?

There is no special preparation for a VCUG. Your child should wear comfortable clothes on the day of the appointment. Please make childcare arrangements for siblings as they will not be allowed into the exam room.

Please note that if you are pregnant, you will not be allowed in the room during the exam and may wish to make arrangements to have someone else be with your child.

What will happen during the exam?

Your child will be asked to change into a gown when you arrive for their appointment. The technologist will bring you and your child to the exam room and explain the procedure. You will also meet the radiologist who will be taking the pictures.

Your child will be asked to lie on their back on the flouroscope table. The radiologist will then clean the area to be catheterized with a brown iodine solution. To introduce the contrast dye into your child’s bladder, we will place a small flexible catheter (a hollow plastic tube) up through the urethra into the bladder. Your child may feel some pressure and think they need to urinate. We will then slowly drip the contrast dye through the tube to expand the bladder.

When the bladder is fully expanded, we will take some pictures. We will then ask your child to empty their bladder onto an absorbent pad on the X-ray table. As your child voids we will record the process with the fluoroscope. The catheter will slide out painlessly while they urinate.

How can I help my child feel comfortable during the exam?

The placement of the catheter may be uncomfortable for your child, especially if they are unable to relax. Many children are also embarrassed by having to void under the camera. You can remain with your child throughout the exam to offer comfort and reassurance. You can help them relax by taking deep breaths together or by distracting them with a song or video. Talk to your child before the exam about what might help them relax.

We can also arrange to have a child life specialist at your child's appointment to help your child better cope with the stress of this exam.

Are there any risks?

This is an X-ray based exam, and your child will be exposed to minimal doses of diagnostic radiation. We adjust the dose of radiation to the size of your child. The risk is small compared to the benefit of an accurate diagnosis or intervention.

After the test

Your child can resume normal activities after the VCUG. A radiologist will analyze the images and share the results with the doctor who requested the exam, who will then discuss the results with you.