What To Expect Before a Chest CT Scan

What To Wear

Wear loose-fitting, comfortable clothing for the test. In some cases, the CT scan technician (a person specially trained to do CT scans) may ask you to wear a hospital gown.

You also may want to avoid wearing jewelry and other metal objects. You’ll be asked to take off any jewelry, eyeglasses, and metal objects that might interfere with the test.

You may be asked to remove hearing aids and dentures as well. Let the technician know if you have any body piercing on your chest.

Pregnancy and Other Conditions

Tell your doctor whether you’re pregnant or may be pregnant. If possible, you should avoid unnecessary radiation exposure during pregnancy. This is because of the concern that radiation may harm the fetus.

You and your doctor will decide whether the benefits of a chest CT scan outweigh the possible risks to the fetus, or whether another test might be better. If you do have the chest CT scan, the technician will take extra steps to reduce the fetus’ exposure to radiation.

You also should tell your doctor whether:

• You’re taking any medicines
• You have any allergies
• You’ve recently been ill
• You have any medical conditions (for example, heart disease, asthma, diabetes, kidney disease, or thyroid problems)

These factors or conditions may raise your risk for a bad reaction to the test.

The CT Machine

The CT scanner is a large machine with a tunnel-like hole in the center. You lie on a table that goes through the hole.

Tell your doctor if you’re afraid of tight or closed spaces. He or she may give you medicine to help you relax. This medicine may make you sleepy, so you’ll need to arrange for a ride home after the test.

Contrast Dye

Your doctor may give you a special substance (called contrast dye). This substance highlights areas of your chest and helps create clearer images.

The contrast dye will be injected into a vein in your arm. You may feel some discomfort when the needle is inserted. As the substance is injected, you also may feel warm and have a metallic taste in your mouth. These feelings last only a few minutes.

Your doctor may ask you not to eat or drink for a few hours before the test, especially if contrast dye is part of the test.

Some people are allergic to the contrast dye. If you have allergic symptoms, such as itching or hives, tell the technician or doctor right away. He or she can give you medicine to relieve the symptoms.

The most common type of contrast dye used in lung CT scans contains iodine. Let your doctor know if you’re allergic to iodine.

If you’re breast-feeding, ask your doctor how long you should wait after the test before you breast-feed. The contrast dye can be passed to your baby through your breast milk.

You may want to prepare for the test by pumping and saving milk for 24 to 48 hours in advance. You can bottle-feed your baby in the hours after the CT scan.

Author/Source: National Heart, Lung & Blood Institute, Division of the National Institutes of Health [NIH]

Retrieved: June 2008