Radionuclide Cystogram

Also known as: RNC, nuclear medicine cystogram

What is a Radionuclide Cystogram?

A cystogram is a nuclear medicine study to check for any possible causes of a urinary tract infection (UTI), or to determine if the child has Vesicoureteral Reflux (VUR), which is when urine flows backwards from the bladder and instead flows towards the kidneys. This type of radiological exam utilizes a minimal and safe amount of a radiopharmaceutical to obtain a detailed picture of the part of the body.

What to Expect During the Procedure

Step 1: Getting Ready

Your child will be given a small radiopharmaceutical through a soft, plastic catheter that is gently inserted into his or her bladder.

To get ready for the plastic catheter, your child will be asked to remove all clothing (including undergarments) and change into a hospital gown.
  • A table with a camera attached underneath will be inside the room (“camera bed”). The camera never moves and never touches the child.  The technologist will then ask you to help your child lie down on the “camera bed” to prepare for the pictures.
  • A member of the medical team will then begin to clean the area where your child urinates. When cleaning the area, they will use soft cotton balls and a soap called “Betadine” (brown soap).
    • Girls will be asked to make “frog legs”, “butterfly wings” or “ballerina legs” (feet together, knees apart while lying down) so that the area can be properly cleaned.
    • Some children say this part feels cold.
  • Next, a lubricated catheter (small, plastic tube covered with jelly) will then be placed as gently as possible into the child’s bladder and taped in place.
    • Your child may feel pressure and or the need to urinate during this time.
    • Encourage your child to take deep breaths to make the catheter insertion easier for the child.

Step 2: Taking Pictures

  • To begin taking pictures, the technologist will position the camera under your child’s bladder and kidneys.
  • Your child has a very important job to hold still like a statue! (Minimal movement is okay.)
  • During the pictures, your child’s bladder will be filled with a small amount of the radioisotope and saline water (a salt water fluid) through the catheter. Eventually, your child will feel a strong urge to use the restroom.

Step 3: Going to the bathroom

  • Once your child’s bladder is full, your child will then empty their bladder by “voiding” or urinating the liquid contrast onto the medical pad placed underneath, while the camera continues to take the last of the pictures.
  • Once your child begins to urinate, the plastic catheter gently slides out on its own or with the help of the technologist (Your child does not feel this).
  • The procedure is complete once your child is able to “void” or empty his or her bladder.
  • Please be aware that your child may have some discomfort when urinating for the first time after the test.  This is temporary and will go away. 

Step 4: Results 

Results will be sent to your doctor within one to two business days.


Reviewed by: Felix I Ramirez-Seijas, MD

This page was last updated on: March 03, 2021 02:01 PM