Computed Tomography (CT)

What is computed tomography?

Computed tomography (CT), sometimes called a CAT scan, uses x-rays and computers to create an image of the inside of your child's body. Most parts of the body can be examined using CT.

The CT machine looks like a giant doughnut. Your child will move through the opening of the doughnut while on the exam table.

The CT machine makes images that are different from a regular x-ray. It makes cross-sectional images of the body, most often referred to as slices. Just imagine looking at a piece of bread from the middle of the loaf. That's what a CT machine can do. The CT scanner takes pictures of different sections or slices of tissue as the body moves through the machine.

What should you do prior to the exam?

There are different preparations to follow according to exactly what type of CT scan your child is having.

If your child is:

Not being sedated and is not receiving radiographic contrast, then there are no special preparations for your child to follow.
Having a CT of the abdomen or pelvis with contrast, there is often a special oral prep for your child to follow. You’ll get a prep kit from the CT department ahead of time along with instructions on how to take the prep. The preps are specific to the study being performed and your child's age.
Being sedated for the exam, please follow these sedation preparation guidelines. Sedation is required for all children ages 6 months to 3 years.
Not being sedated but receiving IV radiographic contrast for the exam, your child may have nothing to eat for two hours prior to the exam. Clear liquids are allowed up to the time of the exam.

If your child has a known allergy to radiographic contrast, additional preparations may be necessary. Please contact your referring physician to ask about these preparations if necessary.

Dress your child comfortably, in clothes that are easily removed (sweat clothes, t-shirts). Your child may be given a gown to change into for the CT scan, if required.
Limit the use of jewelry and/or metal (zippers, snaps) in the area that will be scanned.
If you have copies of your child's previous imaging studies from another institution, please bring them for comparison.

Note: Parents/guardians will be allowed to accompany the child into the exam room; other arrangements should be made for siblings.

Women who are pregnant or may be pregnant will be asked to leave the exam room during the procedure. Please make sure that there is someone else available to accompany the child during the exam, if needed.

What should you expect during the exam?

If your child is receiving contrast and/or sedation, you will first be taken to our nursing station. A nurse will place an IV in your child’s arm, hand or foot. Your child will feel only a little pinch.

You and your child will then be taken to the CT exam room. The technologist will ask why the CT is being performed and explain the procedure to both you and your child. Procedures may vary depending on the part of the body being examined.

The technologist will position your child on the CT table, most likely lying on his back, depending on the body part being examined. The CT scanner has a red light that will shine on your child's body to help ensure that your child is in the right position. A lead shield will be given to your child, as long as it does not interfere with the exam. We will also give you a shield if you’re with your child in the room.

The technologist will ask your child to hold very still during the scan. Any type of movement during a CT scan will make the images look fuzzy, and may have to be repeated. Your child may also have to hold his breath a couple times during the scan.

After the technologist leaves the room, the CT scan will begin. The table will move through the doughnut hole slowly, and may even peek out the other side. The CT scanner makes a small noise like the whirl of a washing machine. A voice recorded in the CT scanner will tell your child when to hold his breath, and when to breathe again.

Your child will not feel the x-rays from the CT scan, but sometimes holding still for a long time can be uncomfortable. The CT scan only takes about five to 15 minutes. Your child may be in the room longer while the images are checked for quality, or if additional images are needed.

The images are displayed on a computer screen and are sent to the Radiologist to be read.

A Child Life Specialist can answer your questions about preparing and supporting your child during the procedure and can even come to your child’s appointment to explain what to expect.