Doctors often use a computed tomography (CT) scan to detect cancer. A CT scan also helps doctors to get more information about the disease after detection. Knowing the cancer’s stage helps both the patient and the doctor to choose the appropriate treatment options. The physician will be able to predict the chances of recovery of a patient using a CT scan.
A CT scan uses x-rays to take pictures of the inside of the body. The x-rays take images from different angles and the computer combines the images into 3D images that are detailed, showing any tumors. A contrast medium may be given before the scan to provide further details on the image. The contrast dye can be administered intravenously or swallowed orally. Before undergoing a CT scan, you will be given instructions on how to prepare such as drinking water starting midnight the night before your appointment and not to eat or drink anything four hours before the scan.
During the CT scan procedure:
- You will change into a hospital gown and remove accessories like earrings, belts, and glasses.
- Depending on the body part being scanned, you may be given a contrast medium to help produce clear pictures of specific parts of the body.
- The technologist will assist in positioning you on the examination table. You may be required to lie on your back, on your side or on your stomach depending on the part of the body being scanned.
- The CT scanner is the shape of a large donut. During scanning, the exam table will slide back and forth through the large hole situated at the center of the machine while the scanner rotates around you. The table may move quickly through the scanner then later move more slowly.
- During the entire scan, you will have to lie still. The technologist will be in the other room watching you through a video camera and communicating through the intercom. They may ask you to hold your breath to get clearer images or may tilt the table to create an appropriate angle for the scan.
The examination takes about an hour, but the CT scanning takes only 10-15 minutes. If you are given an injection, you will feel heat or itching or a metallic taste in your mouth which will later disappear after a few minutes. After the scan, you will be advised to drink lots of water to flush out the contrast medium.