What you can expectBy Mayo Clinic staff
You can have a CT scan done in a hospital or an outpatient facility. CT scans are painless and, with newer machines, typically take only a few minutes to complete.
During the CT scan
CT scanners are shaped like a large doughnut standing on its side. You lie on a narrow table that slides into the "doughnut hole," which is called a gantry. Straps and pillows may help you stay in position. During a CT scan of the head, the table may be fitted with a special cradle that holds your head still.
The table will move slowly through the gantry during the CT scan, as the gantry rotates in a circle around you. Each rotation yields several images of thin slices of your body. You may hear buzzing, clicking and whirring noises.
A technologist will be nearby, in a separate room. You will be able to communicate with the technologist via intercom. The technologist may ask you to hold your breath at certain points to avoid blurring the images.
After the CT scan
After the exam you can return to your normal routine. If you were given a contrast material, you may receive special instructions. In some cases, you may be asked to wait for a short time before leaving to ensure that you feel well after the exam. After the scan, you'll likely be told to drink lots of fluids to help your kidneys remove the contrast material from your body.
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