Painless scan takes X-ray images of cross-sections of the body
A CT or CAT scan is a quick, painless and noninvasive way to check for internal injuries after trauma. It is also used to detect benign or malignant (cancerous) tumors in the body, identify reasons for chest or abdominal pain, diagnose vascular disease or a pulmonary embolism, and get clear images of spinal injuries or skeletal structure problems.
Getting a CT scan involves lying down on a table that slides into the CT scanner, which looks like a big white donut. During the scan, you’ll be asked to be still and hold your breath for a few seconds at a time while an X-ray beam rotates around you, taking pictures of cross-sections of your body. These images are called “slices” and they can be viewed on a computer monitor or printed out on film.
Types of CT scans
A CT scan can be performed on any area of the body. Types of scans include:
- Abdominal and pelvis CT scan
- Head or cranial CT scan
- Cervical, thoracic and lumbosacral spine CT scan (of the neck and middle and lower back)
- Orbit CT scan (of the eye sockets, eyes and surrounding bones)
- Chest CT scan
- Cardiac CT angiogram
CT scans with and without contrast
Some CT scans require contrast, a dye that “highlights” areas of the body and helps the doctor see images more clearly. The contrast may be injected (through a vein, usually in your arm) or it may be swallowed. If the contrast is injected, you may feel some coldness and discomfort in the arm as the dye goes in. If you’re having a CT scan with contrast, you will be asked not to eat or drink anything for four to six hours before your appointment.
Some people are allergic to the contrast dye. Be sure to let your provider know if you have ever had an allergic reaction to the dye. In which case, you may be given medication to prevent a reaction.
While CT scans are not painful, it may uncomfortable to lie on a hard table or to hold your breath while holding a certain position. The technician who is performing your test will talk with you beforehand about what to expect and also how to communicate between scans if you need to take a pause.
CT scans involve the use of slightly more radiation than X-rays. The dosage, however, is very small and there is very little risk to your health from one or several scans. Your risk increases, however, if you are repeatedly exposed to radiation from CT scans. If you have any concerns about excess radiation exposure, be sure to talk with your doctor.