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CT Scan of the Chest: About Your Child's Test

What is it?

A CT (computed tomography) scan uses X-rays to make detailed pictures of structures inside your child's body. A CT scan of the chest can give your doctor information about your child's lungs, heart, and other structures in the chest.

During the test, your child will lie on a moving table that is attached to the CT scanner. The CT scanner is a large doughnut-shaped machine. The table will move in and out of the centre of the machine during the scan.

If you are not pregnant, you can stay in the room with your child during the test. You will wear an apron that protects your body from X-rays.

Why is this test done?

A CT scan can help find problems such as:

  • A chest injury.
  • A mass in the chest.
  • A lung infection.
  • A heart defect.

Your doctor may order a CT scan if an earlier ultrasound test didn't show enough detail about the cause of the problem.

How can you prepare for the test?

  • Let your child know that a CT scan doesn't hurt.
  • If your child gets nervous in tight spaces, ask the doctor if your child will need sedation to help relax before the test.
  • Your child may have contrast materials (dye) put into an I.V. in the arm.

How is the test done?

  • Your child may have contrast materials (dye) put into an I.V. in the arm.
  • Your child will lie on a table that's attached to the CT scanner.
  • The table slides into the round opening of the scanner. The table will move during the scan. The scanner moves within the doughnut-shaped casing around your child's body.
  • Your child will be asked to hold still during the scan. Or a safety strap or device may be used. Your child may also be asked to hold their breath for short periods. You may need to help your child do these things.
  • Your child will be kept safe and comfortable during the test. You may be able to stay in the room with your child. A technologist will watch through a window and talk with your child during the test.

What else should you know about the test?

  • A CT scan does not hurt.
  • If the contrast dye is injected through an I.V., your child may feel a quick sting or pinch when the I.V. is started. The dye may make your child feel warm and flushed and may cause a metallic taste in your child's mouth. Some people feel sick to their stomach or get a headache. The technician will watch for this and give help if needed.

How long does the test take?

  • The test will take about 30 to 60 minutes. Most of this time is spent getting ready for the scan. The actual scan only takes a few minutes.

What are the risks of the test?

The chance of a CT scan causing a problem is small.

  • There is a chance of an allergic reaction to the contrast material.
  • The benefits of medical imaging are much higher than the low risk of problems related to the small amounts of radiation with these tests.
  • It is no longer necessary to cover the pelvis (reproductive organs) with shielding during medical imaging in most cases. No evidence has been found that any damage is done to these organs or cells with the low levels of radiation used now.
  • If your teen is breastfeeding and is concerned about whether the dye used in this test is safe, talk to your teen's doctor. Most experts believe that very little dye passes into breast milk and even less is passed on to the baby. But if your teen prefers, some breast milk may be stored ahead of time and used for a day or two after the test.

What happens after the test?

  • Your child may be able to go home and go back to their usual activities right away, depending on why the test was done and the results.
  • If dye was used, have your child drink lots of liquids for 24 hours after the test, unless your doctor says not to.

Follow-up care is a key part of your child's 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 your child is having problems. It's also a good idea to know your child's test results and keep a list of the medicines your child takes.

Where can you learn more?

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