Thoracic CT
Key points
- Thoracic CT is a computed tomography scan of the chest and upper abdomen.
- The patient will be asked to lie on a narrow table (gantry) that slides into the center of the scanner.
- The health care provider may advise you to avoid eating or drinking for 4 to 6 hours prior to the scan, if contrast dye is to be used.
- The preparation you can provide for this test depends on your child's age and previous experience.
Alternative names
Chest CT; CT scan - lungs; CT scan - chest
Definition
Thoracic CT is a computed tomography scan of the chest and upper abdomen.
How the test is performed
The patient will be asked to lie on a narrow table (gantry) that slides into the center of the scanner. Depending on the study being performed, the patient may need to lie on his/her stomach, back, or side. If contrast media (dye) is to be administered, intravenous access will be placed in a small vein of a hand or arm.
Much like standard photographic cameras, subject motion causes blurred images in CT. Therefore, the technologist operating the scanner and supervising the patient will give instructions through an intercom when to hold one's breath and not move.
As the exam takes place, the gantry will advance small intervals through the scanner. Modern "spiral" scanners can perform the examination in one continuous motion of the gantry. Generally, complete scans will only take a few minutes, however, additional contrast-enhanced or higher-resolution scans will add to the scan time. The newest multi-detector scanners can image the entire body, head to toe, in under 30 seconds.
How to prepare for the test
The health care provider may advise you to avoid eating or drinking for 4 to 6 hours prior to the scan, if contrast dye is to be used.
The CT scanner has a weight limit to prevent damage to the mechanized gantry. Have the health care provider contact the scanner operator if you weigh more than 300 pounds.
Metal interferes with the X-rays, so you may be asked to remove jewelry and wear a hospital gown during the study.
For infants and children:
The preparation you can provide for this test depends on your child's age and previous experience. For specific information regarding how you can prepare your child, see the following topics:
- infant test or procedure preparation (birth to 1 year)
- toddler test or procedure preparation (1 to 3 years)
- preschooler test or procedure preparation (3 to 6 years)
- schoolage test or procedure preparation (6 to 12 years)
- adolescent test or procedure preparation (12 to 18 years)
How the test will feel
The X-rays are painless. The primary discomfort may be from the need to lie still on the table.
Written and revised by
David Cohen, M.D.
Our doctors write and review articles for accuracy and keep them up to date.
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