Health Library

Noninvasive Urodynamics Test

A noninvasive urodynamics is a simple test used to evaluate urinary flow.

Your child will have to urinate (pee) for this test.

Before the Test

• Explain the test to your child in words they can easily understand.
• One hour before your scheduled testing time, have your child finish drinking according to the following guidelines so that they arrive with a full bladder and can urinate for the test:
• 3-6 years old: One 8-ounce glass of liquid; no milk or soda pop
• 6-12 years old: Two 8-ounce glasses of liquid; no milk or soda pop
• Teens: Three 8-ounce glasses of liquid; no milk or soda pop
• Your child may still eat and should take their medicines unless instructed otherwise.
• Once you arrive for the test, register at the front desk. (If your child needs to urinate and cannot hold it, tell the registration staff before letting your child use the restroom.)
• If your child urinates before the test starts, your child may need to drink more fluids and wait 45-60 minutes for the bladder to refill. (You may also need to reschedule your appointment.)
• Allow 15-30 minutes for this appointment.

During the Test

• EMG patches, which look like small square bandages, are placed on the outer thigh and buttocks. These patches are attached to wires that are connected to a computer. They measure your child's muscles, but your child will not feel anything. Your child then sits on a portable toilet and is asked to urinate. Boys may stand. A computer measures the urinary flow.
• After your child urinates, they lie on a bed (fully dressed). An ultrasound (diagnostic test using sound waves to get images) of the bladder is done to measure the amount of urine left in the bladder. A clear gel is put on your child's lower belly for the ultrasound. A picture is made by holding a small object, which looks like a microphone on the lower belly.
• Your child may ask the nurse any questions before and after the test.
• Parents may remain in the room during the test.
• This test does not require a catheter.

After the Test

Your child's doctor will discuss the test results with you at your child's follow-up appointment.